bugfixes and translation

Я без шуток не хожу -
То комменты не коммичу,
То весь класс перепишу

Кволити - не кволити,
Хуй меня уволите

app/src/main/AndroidManifest.xml

@@ -13,6 +13,7 @@
     <uses-permission android:name="android.permission.READ_MEDIA_VIDEO"/>
     <uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE"/>
     <uses-permission android:name="android.permission.INTERNET"/>
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
 
     <application
             android:allowBackup="true"

app/src/main/java/org/foxarmy/barcodescannerforemployees/LoadingDialog.kt

@@ -0,0 +1,14 @@
+package org.foxarmy.barcodescannerforemployees
+
+import android.app.Dialog
+import android.os.Bundle
+import androidx.fragment.app.DialogFragment
+
+class LoadingDialog : DialogFragment() {
+    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
+
+
+
+        return super.onCreateDialog(savedInstanceState)
+    }
+}

app/src/main/java/org/foxarmy/barcodescannerforemployees/Net.kt

@@ -1,5 +1,9 @@
 package org.foxarmy.barcodescannerforemployees
 
+import android.content.Context
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
 import okhttp3.*
 import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.MediaType.Companion.toMediaTypeOrNull
@@ -10,16 +14,38 @@ import org.foxarmy.barcodescannerforemployees.dataclasses.Product
 import java.io.File
 import java.io.FileOutputStream
 import java.io.IOException
-import kotlin.concurrent.thread
+import java.util.concurrent.TimeUnit
 
 class Net {
     var language = "en-US"
     var server = "bsfe.foxarmy.org"
     var token = ""
 
-    fun requestProductFromOnlineDB(barcode: String): String {
-        var response = ""
-        thread {
+    fun serverIsAvailable(context: Context, callback: (Boolean) -> Unit) {
+        if (!isInternetConnectionAvailable(context)) {
+            callback(false)
+        }
+        CoroutineScope(Dispatchers.IO).launch {
+            var flag = false
+            val client = OkHttpClient();
+            val request = Request.Builder()
+                .url("https://$server/status")
+                .get()
+                .build();
+
+            try {
+                val response = client.newCall(request).execute();
+                flag = response.code == 200;
+            } catch (e: Exception) {
+                flag = false;
+            }
+            callback(flag)
+        }
+    }
+
+    fun requestProductFromOnlineDB(barcode: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
             val url = "https://ean-online.ru/match.php"
 
             val client = OkHttpClient()
@@ -35,19 +61,15 @@ class Net {
                 .addHeader("accept-language", language)
                 .build()
 
-            response = client.newCall(request).execute().body!!.string()
-        }.join()
-
-        return if (response == "") {
-            "Not found 404"
-        } else {
-            response
+            response = client.newCall(request).execute()
+            callback(response)
         }
     }
 
-    fun registerAccount(username: String, password: String): Response {
-        lateinit var response: Response
-        thread {
+    fun registerAccount(username: String, password: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
+
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -63,14 +85,13 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun login(username: String, password: String): Response {
-        lateinit var response: Response
-        thread {
+    fun login(username: String, password: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -84,15 +105,19 @@ class Net {
                 .addHeader("accept-language", language)
                 .build()
             response = client.newCall(requestLogin).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun uploadAbstractProduct(groupId: Int, abstractProduct: AbstractProduct, imageFile: File): Response {
-        lateinit var response: Response
+    fun uploadAbstractProduct(
+        groupId: Int,
+        abstractProduct: AbstractProduct,
+        imageFile: File,
+        callback: (Response) -> Unit,
+    ) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val body = MultipartBody.Builder()
@@ -115,16 +140,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun changeUsername(newUsername: String): Response {
+    fun changeUsername(newUsername: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        lateinit var response: Response
-
-        thread {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -139,16 +162,14 @@ class Net {
                 .addHeader("accept-language", language)
                 .build()
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun changePassword(newPassword: String): Response {
+    fun changePassword(newPassword: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        lateinit var response: Response
-
-        thread {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -163,15 +184,12 @@ class Net {
                 .addHeader("accept-language", language)
                 .build()
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun createGroup(name: String, password: String): Response {
-        lateinit var response: Response
-
-        thread {
+    fun createGroup(name: String, password: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -184,19 +202,19 @@ class Net {
                 .addHeader("Authorization", "Bearer $token")
                 .addHeader("accept-language", language)
                 .build()
-            response = client.newCall(request).execute()
-        }.join()
+            val response = client.newCall(request).execute()
 
+            changeGroupPassword(name, password, { responseFromPassword ->
+                callback(response)
+            })
 
-        changeGroupPassword(name, password)
-
-        return response
+        }
     }
 
-    fun joinGroup(id: Int, password: String): Response {
-        lateinit var response: Response
+    fun joinGroup(id: Int, password: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -210,41 +228,38 @@ class Net {
                 .addHeader("accept-language", language)
                 .build()
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun changeGroupPassword(name: String, password: String): Response {
-        lateinit var response: Response
+    fun changeGroupPassword(name: String, password: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
+            getGroupId(name, { groupId ->
+                val client = OkHttpClient()
 
-            val groupId = getGroupId(name);
+                val body = FormBody.Builder()
+                body.add("password", password)
 
-            val client = OkHttpClient()
+                val requestBody = body.build()
 
-            val body = FormBody.Builder()
-            body.add("password", password)
-
-            val requestBody = body.build()
-
-            val request = Request.Builder()
-                .url("https://$server/api/group/password/$groupId")
-                .post(requestBody)
-                .addHeader("Authorization", "Bearer $token")
-                .addHeader("accept-language", language)
-                .build()
-            response = client.newCall(request).execute()
-        }.join()
-
-        return response
+                val request = Request.Builder()
+                    .url("https://$server/api/group/password/$groupId")
+                    .post(requestBody)
+                    .addHeader("Authorization", "Bearer $token")
+                    .addHeader("accept-language", language)
+                    .build()
+                response = client.newCall(request).execute()
+                callback(response)
+            });
+        }
     }
 
-    fun getGroupId(name: String): String {
-        lateinit var response: Response
+    fun getGroupId(name: String, callback: (String) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -254,17 +269,14 @@ class Net {
                 .addHeader("accept-language", language)
                 .build()
             response = client.newCall(request).execute()
-        }.join()
-
-        val responseText = response.body!!.string()
-
-        return responseText
+            callback(response.body!!.string())
+        }
     }
 
-    fun getGroupName(id: Int): String {
-        lateinit var response: Response
+    fun getGroupName(id: Int, callback: (String) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -274,17 +286,14 @@ class Net {
                 .addHeader("accept-language", language)
                 .build()
             response = client.newCall(request).execute()
-        }.join()
-
-        val responseText = response.body!!.string()
-
-        return responseText
+            callback(response.body!!.string())
+        }
     }
 
-    fun getUsersInGroup(groupId: Int): Response {
-        lateinit var response: Response
+    fun getUsersInGroup(groupId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -295,15 +304,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun getMyGroups(): Response {
-        lateinit var response: Response
+    fun getMyGroups(callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -314,15 +322,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun getUsernameById(userId: Int): Response {
-        lateinit var response: Response
+    fun getUsernameById(userId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -333,15 +340,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun getGroupAdminId(groupId: Int): Response {
-        lateinit var response: Response
+    fun getGroupAdminId(groupId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -352,15 +358,19 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun updateAbstractProduct(groupId: Int, abstractProduct: AbstractProduct, imageFile: File): Response {
-        lateinit var response: Response
+    fun updateAbstractProduct(
+        groupId: Int,
+        abstractProduct: AbstractProduct,
+        imageFile: File,
+        callback: (Response) -> Unit,
+    ) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val body = MultipartBody.Builder()
@@ -383,15 +393,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun uploadCategory(groupId: Int, category: Category): Response {
-        lateinit var response: Response
+    fun uploadCategory(groupId: Int, category: Category, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -408,15 +417,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun updateCategory(groupId: Int, category: Category): Response {
-        lateinit var response: Response
+    fun updateCategory(groupId: Int, category: Category, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -433,15 +441,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun uploadProduct(groupId: Int, product: Product): Response {
-        lateinit var response: Response
+    fun uploadProduct(groupId: Int, product: Product, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -461,15 +468,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun updateProduct(groupId: Int, product: Product): Response {
-        lateinit var response: Response
+    fun updateProduct(groupId: Int, product: Product, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val body = FormBody.Builder()
@@ -489,15 +495,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun synchronize(groupId: Int): Response {
-        lateinit var response: Response
+    fun synchronize(groupId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -508,76 +513,41 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun getProduct(groupId: Int, localId: Int): Response {
-        lateinit var response: Response
-
-        thread {
-            val client = OkHttpClient()
-
-            val request = Request.Builder()
-                .url("https://$server/api/product/$groupId/$localId")
-                .get()
-                .addHeader("Authorization", "Bearer $token")
-                .addHeader("accept-language", language)
+    fun downloadImage(url: String, file: File, callback: () -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            val client = OkHttpClient.Builder()
+                .connectTimeout(30, TimeUnit.SECONDS)
+                .readTimeout(10, TimeUnit.MINUTES)
                 .build()
 
-            response = client.newCall(request).execute()
-        }.join()
-
-        return response
-    }
-
-    fun getAbstractProduct(groupId: Int, localId: Int): Response {
-        lateinit var response: Response
-
-        thread {
-            val client = OkHttpClient()
-
-            val request = Request.Builder()
-                .url("https://$server/api/abstractproduct/$groupId/$localId")
-                .get()
-                .addHeader("Authorization", "Bearer $token")
-                .addHeader("accept-language", language)
-                .build()
-
-            response = client.newCall(request).execute()
-        }.join()
-
-        return response
-    }
-
-    fun downloadImage(url: String, file: File) {
-        thread {
-            val client = OkHttpClient()
             val request = Request.Builder()
                 .url(url)
                 .addHeader("Authorization", "Bearer $token")
                 .addHeader("accept-language", language)
                 .build()
 
-            client.newCall(request).execute().use { response ->
-                if (!response.isSuccessful) throw IOException("Unexpected code $response")
+            val response = client.newCall(request).execute()
+            if (!response.isSuccessful) throw IOException("Unexpected code $response")
 
-                val fos = FileOutputStream(file)
+            val fos = FileOutputStream(file)
 
-                response.body?.byteStream()?.use { inputStream ->
-                    fos.use {
-                        inputStream.copyTo(fos)
-                    }
+            response.body?.byteStream()?.use { inputStream ->
+                fos.use {
+                    inputStream.copyTo(fos)
                 }
             }
-        }.join()
+            callback()
+        }
     }
 
-    fun deleteCategory(groupId: Int, localId: Int): Response {
-        lateinit var response: Response
+    fun deleteCategory(groupId: Int, localId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -588,15 +558,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun deleteAbstractProduct(groupId: Int, localId: Int): Response {
-        lateinit var response: Response
+    fun deleteAbstractProduct(groupId: Int, localId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -607,15 +576,14 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
-
-        return response
+            callback(response)
+        }
     }
 
-    fun deleteProduct(groupId: Int, localId: Int): Response {
-        lateinit var response: Response
+    fun deleteProduct(groupId: Int, localId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
 
-        thread {
             val client = OkHttpClient()
 
             val request = Request.Builder()
@@ -626,8 +594,69 @@ class Net {
                 .build()
 
             response = client.newCall(request).execute()
-        }.join()
+            callback(response)
+        }
+    }
 
-        return response
+    fun renameGroup(groupId: Int, newName: String, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
+
+            val client = OkHttpClient()
+
+            val body = FormBody.Builder()
+                .add("name", newName)
+                .build()
+
+            val request = Request.Builder()
+                .url("https://$server/api/group/rename/$groupId")
+                .post(body)
+                .addHeader("Authorization", "Bearer $token")
+                .addHeader("accept-language", language)
+                .build()
+
+            response = client.newCall(request).execute()
+            callback(response)
+        }
+    }
+
+    fun transfer_ownership(groupId: Int, userId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
+
+            val client = OkHttpClient()
+
+            val body = FormBody.Builder()
+                .add("userId", userId.toString())
+                .build()
+
+            val request = Request.Builder()
+                .url("https://$server/api/group/transferOwnership/$groupId")
+                .post(body)
+                .addHeader("Authorization", "Bearer $token")
+                .addHeader("accept-language", language)
+                .build()
+
+            response = client.newCall(request).execute()
+            callback(response)
+        }
+    }
+
+    fun leaveGroup(groupId: Int, callback: (Response) -> Unit) {
+        CoroutineScope(Dispatchers.IO).launch {
+            lateinit var response: Response
+
+            val client = OkHttpClient()
+
+            val request = Request.Builder()
+                .url("https://$server/api/group/leave/$groupId")
+                .get()
+                .addHeader("Authorization", "Bearer $token")
+                .addHeader("accept-language", language)
+                .build()
+
+            response = client.newCall(request).execute()
+            callback(response)
+        }
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/Parser.kt

@@ -14,8 +14,6 @@ class Parser constructor() {
                 text = text.replace(found, "")
                 netWeight = stripNetWeight(found)
                 return Triple(text, netWeight, found)
-            } else {
-                return Triple(text, 0.0, "")
             }
         }
         return Triple("", 0.0, "")
@@ -48,4 +46,4 @@ class Parser constructor() {
 
         return AbstractProduct(0, "", name, netWeight, "", 0, unitNumber)
     }
-}
+}

app/src/main/java/org/foxarmy/barcodescannerforemployees/Utils.kt

@@ -3,21 +3,30 @@ package org.foxarmy.barcodescannerforemployees
 import android.app.Activity
 import android.content.Context
 import android.content.ContextWrapper
+import android.content.Intent
+import android.content.SharedPreferences
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
 import android.graphics.Matrix
 import android.media.ExifInterface
+import android.net.ConnectivityManager
+import android.net.NetworkCapabilities
 import android.net.Uri
 import android.os.Build
 import androidx.annotation.RequiresApi
+import androidx.appcompat.app.AlertDialog
 import androidx.core.content.FileProvider
+import androidx.security.crypto.EncryptedSharedPreferences
+import androidx.security.crypto.MasterKeys
 import com.google.firebase.components.BuildConfig
+import org.foxarmy.barcodescannerforemployees.activities.LoginActivity
 import java.io.File
 import java.io.FileInputStream
 import java.io.FileOutputStream
 import java.security.MessageDigest
 import java.text.SimpleDateFormat
 import java.util.*
+import kotlin.system.exitProcess
 
 fun convertToUnixEpochTimestamp(dateString: String): Long {
     val format = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'")
@@ -27,7 +36,11 @@ fun convertToUnixEpochTimestamp(dateString: String): Long {
 }
 
 fun getImageUri(activity: Activity, imageFile: File): Uri? {
-    return FileProvider.getUriForFile(activity, BuildConfig.APPLICATION_ID + "." + activity.localClassName + ".provider", imageFile)
+    return FileProvider.getUriForFile(
+        activity,
+        BuildConfig.APPLICATION_ID + "." + activity.localClassName + ".provider",
+        imageFile
+    )
 }
 
 @RequiresApi(Build.VERSION_CODES.R)
@@ -47,13 +60,13 @@ fun generateThumbnailForImage(context: Context, imageHash: String) {
     val orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL)
     val matrix = Matrix()
 
-    when(orientation){
+    when (orientation) {
         ExifInterface.ORIENTATION_ROTATE_90 -> matrix.postRotate(90F)
         ExifInterface.ORIENTATION_ROTATE_180 -> matrix.postRotate(180F)
         ExifInterface.ORIENTATION_ROTATE_270 -> matrix.postRotate(270F)
     }
     val rotated = Bitmap.createBitmap(img, 0, 0, img.width, img.height, matrix, true)
-    val scaled = Bitmap.createScaledBitmap(rotated, rotated.width/4, rotated.height/4, true)
+    val scaled = Bitmap.createScaledBitmap(rotated, rotated.width / 4, rotated.height / 4, true)
     scaled.compress(Bitmap.CompressFormat.WEBP_LOSSY, 25, FileOutputStream(thumbnailFile))
 }
 
@@ -64,8 +77,11 @@ fun String.md5(): String {
     return digest.toHexString()
 }
 
-fun stripNetWeight (netWeight: String): Double {
-    return removeSubstringsFromString(netWeight, arrayOf("Л", "л", "мл", "Мл", "г", "Г", "кг", "Кг", "шт", "Шт", ",", " ", ".")).toDouble()
+fun stripNetWeight(netWeight: String): Double {
+    return removeSubstringsFromString(
+        netWeight,
+        arrayOf("Л", "л", "мл", "Мл", "г", "Г", "кг", "Кг", "шт", "Шт", ",", " ", ".")
+    ).toDouble()
 }
 
 fun removeSubstringsFromString(text: String, toRemove: Array<String>): String {
@@ -99,21 +115,30 @@ fun calculateProductFreshness(dateOfProduction: Long, dateOfExpiry: Long): Doubl
     return lifeSpanLeft / productLifeSpan.toDouble()
 }
 
-fun getUnitNameById (context: Context, id: Int): String {
-    return when(id) {
+fun getUnitNameById(context: Context, id: Int): String {
+    return when (id) {
         0 -> { context.getString(R.string.kilogram) }
+
         1 -> { context.getString(R.string.gram) }
+
         2 -> { context.getString(R.string.liter) }
+
         3 -> { context.getString(R.string.milliliter) }
+
         4 -> { context.getString(R.string.pieces) }
+
         else -> { "" }
     }
 }
 
-fun parseArray(input: String): IntArray {
+fun parseIntArray(input: String): IntArray {
     return input.trim('[', ']').split(",").map { it.trim().toInt() }.toIntArray()
 }
 
+fun parseStringList(input: String): List<String> {
+    return input.trim('[', ']').split(",").map { it.trim() }.toList()
+}
+
 fun calculateMd5Hash(file: File): String {
     val digest = MessageDigest.getInstance("MD5")
     val fis = FileInputStream(file)
@@ -137,4 +162,56 @@ fun bytesToHex(bytes: ByteArray): String {
         hexString.append(hex)
     }
     return hexString.toString()
+}
+
+fun isInternetConnectionAvailable(context: Context): Boolean {
+    if (context.getSystemService(Context.CONNECTIVITY_SERVICE) == null) return false
+    val connectivityManager =
+        context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
+    if (connectivityManager != null) {
+        val capabilities =
+            connectivityManager.getNetworkCapabilities(connectivityManager.activeNetwork)
+        if (capabilities != null) {
+            if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
+                return true
+            } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
+                return true
+            } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET)) {
+                return true
+            }
+        }
+    }
+    return false
+}
+
+fun noInternetConnectionAvailableNotification(context: Context) {
+    (context as Activity).runOnUiThread {
+        AlertDialog.Builder(context)
+            .setMessage(context.getString(R.string.no_internet_connection))
+            .setCancelable(false)
+            .setPositiveButton(R.string.quit) { _, _ ->
+                exitProcess(0)
+            }
+            .setNeutralButton(R.string.logout) { _, _ ->
+                val sharedPreferences = getPreferences(context)
+
+                sharedPreferences.edit().putString("token", "").apply()
+                sharedPreferences.edit().putString("server", "").apply()
+                sharedPreferences.edit().putStringSet("groups", emptySet()).apply()
+                sharedPreferences.edit().putString("currentGroup", "").apply()
+                val intent = Intent(context, LoginActivity::class.java)
+                context.startActivity(intent)
+                context.finish()
+            }.show()
+    }
+}
+
+fun getPreferences(context: Context): SharedPreferences {
+    return EncryptedSharedPreferences.create(
+        "sensitive",
+        MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
+        context,
+        EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
+        EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
+    )
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/WebSocketClient.kt

@@ -0,0 +1,182 @@
+package org.foxarmy.barcodescannerforemployees
+
+import android.content.Context
+import android.os.Build
+import android.util.Log
+import androidx.annotation.RequiresApi
+import okhttp3.*
+import org.foxarmy.barcodescannerforemployees.activities.MainActivity
+import org.foxarmy.barcodescannerforemployees.database.AbstractProductDAO
+import org.foxarmy.barcodescannerforemployees.database.CategoryDAO
+import org.foxarmy.barcodescannerforemployees.database.DBStorageController
+import org.foxarmy.barcodescannerforemployees.database.ProductDAO
+import org.foxarmy.barcodescannerforemployees.dataclasses.AbstractProduct
+import org.foxarmy.barcodescannerforemployees.dataclasses.Category
+import org.foxarmy.barcodescannerforemployees.dataclasses.Product
+import org.json.JSONObject
+import java.io.File
+import java.util.concurrent.TimeUnit
+
+class WebSocketClient(private val context: Context, private val server: String) {
+
+    private lateinit var webSocket: WebSocket
+    private lateinit var token: String
+    private lateinit var currentGroup: String
+
+    fun connect(token: String, currentGroup: String) {
+        this.token = token
+        this.currentGroup = currentGroup
+
+        val client = OkHttpClient.Builder()
+            .connectTimeout(5, TimeUnit.SECONDS)
+            .readTimeout(1, TimeUnit.MINUTES)
+            .writeTimeout(10, TimeUnit.SECONDS)
+            .callTimeout(1, TimeUnit.MINUTES)
+            .build()
+
+        val request = Request.Builder()
+            .url("wss://$server")
+            .build()
+
+        client.newWebSocket(request, object : WebSocketListener() {
+            override fun onOpen(webSocket: WebSocket, response: Response) {
+                this@WebSocketClient.webSocket = webSocket
+                sendMessage("{\"token\":\"$token\",\"currentGroup\":\"$currentGroup\"}")
+                keepAlive()
+            }
+
+            @RequiresApi(Build.VERSION_CODES.O)
+            override fun onMessage(webSocket: WebSocket, text: String) {
+                val payload = JSONObject(text)
+
+                val item = payload["item"] as String
+                val data = payload["data"] as JSONObject
+                val action = payload["action"] as String
+                val currentGroup = payload["groupId"] as String
+
+                val dbHelper = DBStorageController(context, currentGroup)
+                val abstractProductDAO = AbstractProductDAO(dbHelper)
+                val productDAO = ProductDAO(dbHelper)
+                val categoryDAO = CategoryDAO(dbHelper)
+
+                when (action) {
+                    "create" -> {
+                        when (item) {
+                            "abstractproduct" -> {
+                                val newAbstractProduct = AbstractProduct.createFromJSON(data)
+
+                                val net = Net()
+                                net.server = server
+                                net.token = token
+
+                                val picturesDir = File(context.filesDir, "pictures")
+                                picturesDir.mkdirs()
+
+                                val pictureFile =
+                                    File(picturesDir, "${data["image_filename"]}.png")
+                                val url = "https://${net.server}/api/abstractproduct/getImage/${currentGroup}/${data["local_id"]}"
+                                net.downloadImage(url, pictureFile, {
+                                    abstractProductDAO.addAbstractProduct(newAbstractProduct)
+                                    (context as MainActivity).updateAll()
+                                })
+                            }
+
+                            "product" -> {
+                                val newProduct = Product.createFromJSON(data)
+                                productDAO.insertNewProduct(newProduct)
+                                (context as MainActivity).updateAll()
+                            }
+
+                            "category" -> {
+                                val newCategory = Category.createFromJSON(data)
+                                categoryDAO.addCategory(newCategory)
+                                (context as MainActivity).updateAll()
+                            }
+                        }
+                    }
+
+                    "update" -> {
+                        when (item) {
+                            "abstractproduct" -> {
+                                val updatedAbstractProduct = AbstractProduct.createFromJSON(data)
+
+                                val net = Net()
+                                net.server = server
+                                net.token = token
+
+                                val picturesDir = File(context.filesDir, "pictures")
+                                picturesDir.mkdirs()
+
+                                val pictureFile =
+                                    File(picturesDir, "${data["image_filename"]}.png")
+                                val url = "https://${net.server}/api/abstractproduct/getImage/${currentGroup}/${data["local_id"]}"
+                                net.downloadImage(url, pictureFile, {
+                                    abstractProductDAO.updateAbstractProduct(updatedAbstractProduct)
+                                    (context as MainActivity).updateAll()
+                                })
+
+                            }
+                            "product" -> {
+                                val updatedProduct = Product.createFromJSON(data)
+                                productDAO.updateProduct(updatedProduct)
+                                (context as MainActivity).updateAll()
+                            }
+                            "category" -> {
+                                val updatedCategory = Category.createFromJSON(data)
+                                categoryDAO.updateCategory(updatedCategory)
+                                (context as MainActivity).updateAll()
+                            }
+                        }
+                    }
+
+                    "delete" -> {
+                        val id = data["local_id"] as String
+
+                        when(item) {
+                            "abstractproduct" -> {
+                                abstractProductDAO.eraseAbstractProduct(id.toInt(), context)
+                                (context as MainActivity).updateAll()
+                            }
+                            "product" -> {
+                                productDAO.eraseProduct(id.toInt())
+                                (context as MainActivity).updateAll()
+                            }
+                            "category" -> {
+                                categoryDAO.eraseCategory(id.toInt(), context)
+                                (context as MainActivity).updateAll()
+                            }
+                        }
+                    }
+                }
+            }
+
+            override fun onClosing(webSocket: WebSocket, code: Int, reason: String) {
+                Log.d("QWERTYUIOP", "Closing ws. Reason: $reason")
+//                noInternetConnectionAvailableNotification(context)
+                this@WebSocketClient.connect(token, currentGroup)
+            }
+
+            override fun onFailure(webSocket: WebSocket, t: Throwable, response: Response?) {
+                Log.d("QWERTYUIOP","Connection failed: ${t.message}")
+                noInternetConnectionAvailableNotification(context)
+            }
+        })
+    }
+
+    private fun keepAlive() {
+        Thread {
+            while (true) {
+                Thread.sleep(30000)
+                webSocket.send("keepalive")
+            }
+        }.start()
+    }
+
+    fun sendMessage(message: String) {
+        webSocket.send(message)
+    }
+
+    fun close() {
+        webSocket.close(1000, "Closing WebSocket connection")
+    }
+}

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/AccountSettingsActivity.kt

@@ -1,11 +1,11 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
+import android.content.Intent
 import android.os.Bundle
 import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
+import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.databinding.ActivityAccountSettingsBinding
 
 class AccountSettingsActivity : AppCompatActivity() {
@@ -19,15 +19,7 @@ class AccountSettingsActivity : AppCompatActivity() {
 
         setContentView(binding.root)
 
-        val masterKeyAlias = MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC)
-
-        val sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            masterKeyAlias,
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        val sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         val net = Net()
 
@@ -36,13 +28,39 @@ class AccountSettingsActivity : AppCompatActivity() {
         net.token = sharedPreferences.getString("token", "")!!
 
         binding.saveUsernameButton.setOnClickListener {
-            val response = net.changeUsername(binding.newUsernameTextEdit.text.toString())
-            Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
+            net.changeUsername(binding.newUsernameTextEdit.text.toString(), { response ->
+                if (response.code == 200) {
+                    runOnUiThread {
+                        Toast.makeText(this, getString(R.string.username_changed), Toast.LENGTH_LONG).show()
+                        val intent = Intent(this, LoginActivity::class.java)
+                        startActivity(intent)
+                        finish()
+                    }
+                } else {
+                    runOnUiThread {
+                        Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
+                    }
+                }
+            })
+
         }
 
         binding.savePasswordButton.setOnClickListener {
-            val response = net.changePassword(binding.newPasswordTextEdit.text.toString())
-            Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
+            net.changePassword(binding.newPasswordTextEdit.text.toString(), { response ->
+                if (response.code == 200) {
+                    runOnUiThread {
+                        Toast.makeText(this, getString(R.string.password_changed), Toast.LENGTH_LONG).show()
+                        val intent = Intent(this, LoginActivity::class.java)
+                        startActivity(intent)
+                        finish()
+                    }
+                } else {
+                    runOnUiThread {
+                        Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
+                    }
+                }
+            })
+
         }
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/AddAbstractProductActivity.kt

@@ -1,5 +1,6 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
+import android.app.ProgressDialog
 import android.content.DialogInterface
 import android.content.Intent
 import android.content.SharedPreferences
@@ -17,8 +18,6 @@ import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.content.ContextCompat
 import androidx.core.widget.addTextChangedListener
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import com.journeyapps.barcodescanner.ScanContract
 import com.journeyapps.barcodescanner.ScanIntentResult
 import com.journeyapps.barcodescanner.ScanOptions
@@ -32,7 +31,6 @@ import java.io.File
 import java.io.FileOutputStream
 import java.nio.file.Files
 import java.nio.file.StandardCopyOption
-import kotlin.concurrent.thread
 
 class AddAbstractProductActivity : AppCompatActivity() {
     private lateinit var imageView: ImageView
@@ -60,20 +58,21 @@ class AddAbstractProductActivity : AppCompatActivity() {
     private lateinit var DAO: AbstractProductDAO
     private lateinit var sharedPreferences: SharedPreferences
 
+    private lateinit var loadingDialog: ProgressDialog
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
         setContentView(R.layout.fragment_add_abstract_product)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        loadingDialog = ProgressDialog(this)
+        loadingDialog.setMessage(getString(R.string.loading_please_wait))
+        loadingDialog.setCancelable(false)
+        loadingDialog.setTitle(getString(R.string.loading))
 
-        val dbHelper = DBStorageController(this, sharedPreferences.getString("currentGroup", "database")!!)
+        sharedPreferences = getPreferences(this)
+
+        val dbHelper = DBStorageController(this, sharedPreferences.getString("currentGroup", "offline")!!)
         DAO = AbstractProductDAO(dbHelper)
 
         picturesPath = File(filesDir, "pictures")
@@ -109,25 +108,28 @@ class AddAbstractProductActivity : AppCompatActivity() {
         action = extras!!.get("action") as String
         when (action) {
             "update" -> {
-                abstractProduct = extras.get("abstractProduct") as AbstractProduct?
+                abstractProduct = extras.get("abstractProduct") as AbstractProduct
             }
 
             "new_from_barcode" -> {
-                abstractProduct = extras.get("abstractProduct") as AbstractProduct?
+                abstractProduct = extras.get("abstractProduct") as AbstractProduct
                 barcode = abstractProduct!!.barcode
                 performRequest(abstractProduct!!.barcode)
             }
         }
 
-        if (abstractProduct != null) {
+        if (abstractProduct != null && action == "update") {
             val imageThumbnailUri = getImageUri(this, File(thumbnailsDir, "${abstractProduct!!.imageHash}.webp"))
-            pictureFile = File(picturesPath, "${abstractProduct!!.imageHash}.png]")
+            pictureFile = File(picturesPath, "${abstractProduct!!.imageHash}.png")
             imageView.setImageURI(imageThumbnailUri)
             barcodeText.setText(abstractProduct!!.barcode)
             productNameText.text = abstractProduct!!.name
             netWeightText.text = abstractProduct!!.netWeight.toString()
-            categorySpinner.setSelection(abstractProduct!!.category)
+            categorySpinner.setSelection(abstractProduct!!.category - 1)
             unitTypeSpinner.setSelection(abstractProduct!!.unit)
+            if (abstractProduct!!.barcode == "" || abstractProduct!!.barcode == "             ") {
+                noBarcodeCheckBox.isChecked = true
+            }
         }
 
         saveButton.setOnClickListener {
@@ -149,20 +151,29 @@ class AddAbstractProductActivity : AppCompatActivity() {
             }
             if (netWeight.toString() == "" || netWeight.toString().toDoubleOrNull() == null) {
                 Toast.makeText(this, getString(R.string.product_net_weight_request), Toast.LENGTH_SHORT).show()
+                return@setOnClickListener
             }
 
+            loadingDialog.show()
+
+            val currentGroup: Int
+            val currentGroupString = sharedPreferences.getString("currentGroup", "offline")!!
+
             val net = Net()
 
-            net.token = sharedPreferences.getString("token", "")!!
-            net.server = sharedPreferences.getString("server", "")!!
-            net.language = sharedPreferences.getString("language", "en-US")!!
+            if (currentGroupString != "offline") {
+                currentGroup = currentGroupString.toInt()
 
-            val currentGroup = sharedPreferences.getString("currentGroup", "offline")!!
+                net.token = sharedPreferences.getString("token", "")!!
+                net.server = sharedPreferences.getString("server", "")!!
+                net.language = sharedPreferences.getString("language", "en-US")!!
 
-            lateinit var response: Response
+            } else {
+                currentGroup = 0
+            }
 
             abstractProduct = AbstractProduct(
-                if(abstractProduct == null) 0 else abstractProduct!!.id,
+                if (abstractProduct == null) 0 else abstractProduct!!.id,
                 if (noBarcodeCheckBox.isChecked) "" else barcode,
                 productName,
                 netWeight.toString().toDouble(),
@@ -170,18 +181,17 @@ class AddAbstractProductActivity : AppCompatActivity() {
                 categorySpinner.selectedItemPosition + 1,
                 unitTypeSpinner.selectedItemPosition
             )
+
             val pictureFile = File(File(filesDir, "pictures"), "${abstractProduct!!.imageHash}.png")
 
             if (action == "update") {
                 DAO.updateAbstractProduct(abstractProduct!!)
-                response = net.updateAbstractProduct(currentGroup.toInt(), abstractProduct!!, pictureFile)
+                if (currentGroup > 0) net.updateAbstractProduct(currentGroup, abstractProduct!!, pictureFile, this::notifyUserAndExit)
             } else if (action == "new" || action == "new_from_barcode") {
                 abstractProduct!!.id = DAO.addAbstractProduct(abstractProduct!!).toInt()
-                response = net.uploadAbstractProduct(currentGroup.toInt(), abstractProduct!!, pictureFile);
+                if (currentGroup > 0)
+                    net.uploadAbstractProduct(currentGroup, abstractProduct!!, pictureFile, this::notifyUserAndExit)
             }
-            Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
-
-            finish()
         }
 
         takePictureButton.setOnClickListener {
@@ -194,11 +204,16 @@ class AddAbstractProductActivity : AppCompatActivity() {
         }
     }
 
+    fun notifyUserAndExit(response: Response) {
+        runOnUiThread {
+            Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
+            loadingDialog.dismiss()
+            finish()
+        }
+    }
+
     fun performRequest(barcode: String) {
         barcodeText.setText(this.barcode)
-        val net = Net();
-        val result = net.requestProductFromOnlineDB(barcode)
-        Log.d("QWERTYUIOP", "Result of request: $result")
 
         var abstractProduct: AbstractProduct
 
@@ -220,24 +235,25 @@ class AddAbstractProductActivity : AppCompatActivity() {
                 }.show()
         }
 
-        thread {
-            if (result == "Not found 404") {
+        val net = Net();
+        net.requestProductFromOnlineDB(barcode, {response ->
+            if (response.code == 404) {
                 runOnUiThread {
                     Toast.makeText(this, getString(R.string.no_product_in_online_database), Toast.LENGTH_LONG)
                         .show()
                     productNameText.setText("")
                     netWeightText.setText("")
                 }
-                return@thread
+                return@requestProductFromOnlineDB
             }
 
-            abstractProduct = Parser().parse(result)
+            abstractProduct = Parser().parse(response.body!!.string())
             runOnUiThread {
                 productNameText.text = abstractProduct.name
                 netWeightText.text = abstractProduct.netWeight.toString()
                 unitTypeSpinner.setSelection(abstractProduct.unit)
             }
-        }
+        })
     }
 
     private fun fillupUnitsSpinner() {
@@ -257,7 +273,8 @@ class AddAbstractProductActivity : AppCompatActivity() {
 
     fun fillupCategorySpinner() {
 
-        val categoriesDAO = CategoryDAO(DBStorageController(this, sharedPreferences.getString("currentGroup", "database")!!))
+        val categoriesDAO =
+            CategoryDAO(DBStorageController(this, sharedPreferences.getString("currentGroup", "database")!!))
 
         val categories = categoriesDAO.getAllCategories().map { category -> category.name }
 
@@ -272,22 +289,15 @@ class AddAbstractProductActivity : AppCompatActivity() {
         if (success) {
             //Move picture to a proper directory according to its calculated hash
             val tempfile = File(filesDir, "image.png")
-            val imageHash = calculateMd5Hash(tempfile)
-//            val imageContent = tempfile.inputStream().readBytes()
-//            val imageHash = imageContent.toString(Charsets.UTF_8).md5()
 
-            pictureFile = File(picturesPath, "$imageHash.png")
-            Files.move(tempfile.toPath(), pictureFile.toPath(), StandardCopyOption.REPLACE_EXISTING)
-            tempfile.delete()
-
-            val imageContent = pictureFile.inputStream().readBytes()
+            val imageContent = tempfile.inputStream().readBytes()
             var img = BitmapFactory.decodeByteArray(imageContent, 0, imageContent.size)
 
-            val exif = ExifInterface(pictureFile.absoluteFile.toString())
+            val exif = ExifInterface(tempfile.absoluteFile.toString())
             val orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL)
             val matrix = Matrix()
 
-            when(orientation){
+            when (orientation) {
                 ExifInterface.ORIENTATION_ROTATE_90 -> matrix.postRotate(90F)
                 ExifInterface.ORIENTATION_ROTATE_180 -> matrix.postRotate(180F)
                 ExifInterface.ORIENTATION_ROTATE_270 -> matrix.postRotate(270F)
@@ -298,9 +308,15 @@ class AddAbstractProductActivity : AppCompatActivity() {
             rotated.compress(
                 Bitmap.CompressFormat.WEBP_LOSSY,
                 100 * (15 / (16 - compressionFactor)),
-                FileOutputStream(pictureFile)
+                FileOutputStream(tempfile)
             )
 
+            val imageHash = calculateMd5Hash(tempfile)
+
+            pictureFile = File(picturesPath, "$imageHash.png")
+            Files.move(tempfile.toPath(), pictureFile.toPath(), StandardCopyOption.REPLACE_EXISTING)
+            tempfile.delete()
+
             generateThumbnailForImage(this, imageHash)
 
             imageView.setImageURI(getImageUri(this, pictureFile))

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/AddCategoryActivity.kt

@@ -1,13 +1,13 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
 import android.app.Activity
+import android.app.ProgressDialog
 import android.content.SharedPreferences
 import android.os.Bundle
 import android.widget.Button
 import android.widget.EditText
 import android.widget.Toast
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
+import okhttp3.Response
 import org.foxarmy.barcodescannerforemployees.Net
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.database.CategoryDAO
@@ -18,19 +18,19 @@ class AddCategoryActivity : Activity() {
 
     private lateinit var DAO: CategoryDAO
     private lateinit var sharedPreferences: SharedPreferences
+    private lateinit var loadingDialog: ProgressDialog
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
         setContentView(R.layout.activity_add_category)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        loadingDialog = ProgressDialog(this)
+        loadingDialog.setMessage(getString(R.string.loading_please_wait))
+        loadingDialog.setCancelable(false)
+        loadingDialog.setTitle(getString(R.string.loading))
+
+        sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         val dbHelper = DBStorageController(this, sharedPreferences.getString("currentGroup", "offline")!!)
         DAO = CategoryDAO(dbHelper)
@@ -48,25 +48,35 @@ class AddCategoryActivity : Activity() {
         net.server = sharedPreferences.getString("server", "")!!
         net.language = sharedPreferences.getString("language", "")!!
 
-        val currentGroup = sharedPreferences.getString("currentGroup", "offline")!!.toInt()
+        val currentGroup: Int = if (sharedPreferences.getString(
+                "currentGroup",
+                "offline"
+            )!! == "offline"
+        ) 0 else sharedPreferences.getString("currentGroup", "")!!.toInt()
 
         findViewById<Button>(R.id.saveButton).setOnClickListener {
             if (categoryNameTextEdit.text.toString() == "") {
                 Toast.makeText(this, getString(R.string.category_name_required), Toast.LENGTH_SHORT).show()
                 return@setOnClickListener
             }
+            loadingDialog.show()
 
             if (category.id == 0) { // Inserting new category
                 val newCategory = Category(0, categoryNameTextEdit.text.toString())
                 newCategory.id = DAO.addCategory(newCategory).toInt()
-                net.uploadCategory(currentGroup, newCategory)
+                if (currentGroup > 0) net.uploadCategory(currentGroup, newCategory, this::notifyUserAndExit)
             } else { // Updating existing category
                 category.name = categoryNameTextEdit.text.toString()
                 DAO.updateCategory(category)
-                net.updateCategory(currentGroup, category)
+                if (currentGroup > 0) net.updateCategory(currentGroup, category, this::notifyUserAndExit)
             }
-
-            finish()
         }
     }
+    fun notifyUserAndExit(response: Response) {
+        runOnUiThread {
+            Toast.makeText(this, response.body!!.string(), Toast.LENGTH_SHORT).show()
+        }
+        loadingDialog.dismiss()
+        finish()
+    }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/AddProductActivity.kt

@@ -1,6 +1,7 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
 import android.app.Activity
+import android.app.ProgressDialog
 import android.content.Intent
 import android.content.SharedPreferences
 import android.os.Build
@@ -13,8 +14,6 @@ import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.content.ContextCompat
 import androidx.core.widget.addTextChangedListener
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import com.journeyapps.barcodescanner.ScanContract
 import com.journeyapps.barcodescanner.ScanIntentResult
 import com.journeyapps.barcodescanner.ScanOptions
@@ -56,18 +55,19 @@ class AddProductActivity : AppCompatActivity() {
     private lateinit var abstractProductDAO: AbstractProductDAO
     private lateinit var sharedPreferences: SharedPreferences
 
+    private lateinit var loadingDialog: ProgressDialog
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
         setContentView(R.layout.fragment_add_product)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        loadingDialog = ProgressDialog(this)
+        loadingDialog.setMessage(getString(R.string.loading_please_wait))
+        loadingDialog.setCancelable(false)
+        loadingDialog.setTitle(getString(R.string.loading))
+
+        sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         val dbHelper = DBStorageController(this, sharedPreferences.getString("currentGroup", "offline")!!)
         productDAO = ProductDAO(dbHelper)
@@ -177,31 +177,36 @@ class AddProductActivity : AppCompatActivity() {
                 return@setOnClickListener
             }
 
-            val currentGroup: Int = if (sharedPreferences.getString("currentGroup", "")!! == "") 0 else sharedPreferences.getString("currentGroup", "")!!.toInt()
+            loadingDialog.show()
 
-            var response: Response? = null
+            val currentGroup: Int = if (sharedPreferences.getString("currentGroup", "offline")!! == "offline") 0 else sharedPreferences.getString("currentGroup", "")!!.toInt()
 
             if (updatingExistentProduct) {
                 productDAO.updateProduct(product!!)
-                if (currentGroup > 0) response = net.updateProduct(currentGroup, product!!)
+                if (currentGroup > 0) net.updateProduct(currentGroup, product!!, this::notifyUserAndExit)
             } else {
                 product!!.id = productDAO.insertNewProduct(product!!).toInt()
-                if (currentGroup > 0) response = net.uploadProduct(currentGroup, product!!)
+                if (currentGroup > 0) net.uploadProduct(currentGroup, product!!, this::notifyUserAndExit)
             }
-
-            if (response != null) {
-                Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
-            }   
-
-            finish()
         }
         update()
 
         val today = SimpleDateFormat("dd.MM.yyyy").format(Calendar.getInstance().time).split(".")
 
 
-        dateOfProductionDatePicker.updateDate(today[2].toInt(), today[1].toInt(), today[0].toInt())
-        expiryDatePicker.updateDate(today[2].toInt(), today[1].toInt(), today[0].toInt())
+        dateOfProductionDatePicker.updateDate(today[2].toInt(), today[1].toInt() - 1, today[0].toInt())
+        expiryDatePicker.updateDate(today[2].toInt(), today[1].toInt() - 1, today[0].toInt())
+        product!!.dateOfProduction = SimpleDateFormat("dd.MM.yyyy").parse("${today[0]}.${today[1]}.${today[2]}")!!.time / 1000
+
+
+    }
+
+    fun notifyUserAndExit(response: Response) {
+        runOnUiThread {
+            Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
+            loadingDialog.dismiss()
+            finish()
+        }
     }
 
     private val intentLauncher =

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/ExpiryCalendarActivity.kt

@@ -7,8 +7,6 @@ import android.os.Bundle
 import android.widget.LinearLayout
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.content.ContextCompat
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
 import org.foxarmy.barcodescannerforemployees.database.ProductDAO
@@ -26,13 +24,7 @@ class ExpiryCalendarActivity : AppCompatActivity() {
 
         setContentView(R.layout.fragment_expiry_dates)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         val dbHelper = DBStorageController(this, sharedPreferences.getString("currentGroup", "database")!!)
         productDAO = ProductDAO(dbHelper)

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/FindBarcodelessAbstractProduct.kt

@@ -18,7 +18,7 @@ class FindBarcodelessAbstractProduct() : AppCompatActivity() {
         binding = ActivityFindBarcodelessAbstractProductBinding.inflate(layoutInflater)
 
         val ft = supportFragmentManager.beginTransaction()
-        val fragment = StorageFragment.newInstance("barcodeless", arrayOf("", "             "))
+        val fragment = StorageFragment.newInstance("barcodeless", arrayOf("", "             ", " "))
         ft.replace(R.id.content, fragment)
         ft.commit()
 

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/FullscreenActivity.kt

@@ -15,10 +15,7 @@ import java.io.File
 
 class FullscreenActivity : Activity() {
 
-    private lateinit var binding: ActivityFullscreenBinding
     private lateinit var fullscreenImageView: ImageView
-    private lateinit var fullscreenContentControls: LinearLayout
-    private val hideHandler = Handler(Looper.myLooper()!!)
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/GroupActivity.kt

@@ -1,13 +1,14 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
+import android.app.ProgressDialog
 import android.content.Intent
 import android.os.Bundle
 import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
+import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.databinding.ActivityGroupBinding
+import org.foxarmy.barcodescannerforemployees.noInternetConnectionAvailableNotification
 
 class GroupActivity : AppCompatActivity() {
 
@@ -19,62 +20,103 @@ class GroupActivity : AppCompatActivity() {
         binding = ActivityGroupBinding.inflate(layoutInflater)
         setContentView(binding.root)
 
-        val sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        val loadingDialog = ProgressDialog(this)
+        loadingDialog.setMessage(getString(R.string.loading_please_wait))
+        loadingDialog.setCancelable(false)
+        loadingDialog.setTitle(getString(R.string.loading))
+
+        val sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         binding.createGroupButton.setOnClickListener {
             val groupName = binding.groupNameTextEdit.text.toString()
             val groupPassword = binding.groupPasswordTextEdit.text.toString()
-            // group is set to "successful"
-            val n = Net()
-            n.language = sharedPreferences.getString("language", "en-US")!!
-            n.server = sharedPreferences.getString("server", "")!!
-            n.token = sharedPreferences.getString("token", "")!!
+            val net = Net()
+            net.language = sharedPreferences.getString("language", "en-US")!!
+            net.server = sharedPreferences.getString("server", "")!!
+            net.token = sharedPreferences.getString("token", "")!!
 
-            val response = n.createGroup(groupName, groupPassword)
-            val responseText = response.body!!.string()
+            net.serverIsAvailable(this, { isServerAvailable ->
+                if (!isServerAvailable) {
+                    noInternetConnectionAvailableNotification(this)
+                } else {
+                    runOnUiThread {
+                        loadingDialog.show()
+                    }
+                    net.createGroup(groupName, groupPassword, { response ->
+                        val responseText = response.body!!.string()
 
-            if (response.code == 200) {
-                val currentGroups = sharedPreferences.getStringSet("groups", mutableSetOf())
-                currentGroups!!.add(responseText)
-                sharedPreferences.edit().putStringSet("groups", currentGroups).apply()
-                sharedPreferences.edit().putString("currentGroup", responseText).apply()
-                val intent = Intent(this, MainActivity::class.java)
-                startActivity(intent)
-                finish()
-            } else {
-                Toast.makeText(this, responseText, Toast.LENGTH_LONG).show()
-            }
+                        if (response.code == 200) {
+                            val currentGroups = sharedPreferences.getStringSet("groups", mutableSetOf())
+                            currentGroups!!.add(responseText)
+                            sharedPreferences.edit().putStringSet("groups", currentGroups).apply()
+                            sharedPreferences.edit().putString("currentGroup", responseText).apply()
+                            runOnUiThread {
+                                val intent = Intent(this, MainActivity::class.java)
+                                startActivity(intent)
+                                loadingDialog.dismiss()
+                                finish()
+                            }
+                        } else {
+                            runOnUiThread {
+                                loadingDialog.dismiss()
+                                Toast.makeText(this, responseText, Toast.LENGTH_LONG).show()
+                            }
+                        }
+                    })
+                }
+            })
         }
 
         binding.joinGroupButton.setOnClickListener {
             val groupName = binding.groupNameTextEdit.text.toString()
             val groupPassword = binding.groupPasswordTextEdit.text.toString()
 
-            val n = Net()
-            n.language = sharedPreferences.getString("language", "en-US")!!
-            n.server = sharedPreferences.getString("server", "")!!
-            n.token = sharedPreferences.getString("token", "")!!
+            val net = Net()
+            net.language = sharedPreferences.getString("language", "en-US")!!
+            net.server = sharedPreferences.getString("server", "")!!
+            net.token = sharedPreferences.getString("token", "")!!
 
-            val groupId = n.getGroupId(groupName).toInt()
-            val response = n.joinGroup(groupId, groupPassword)
-            val responseText = response.body!!.string()
+            net.serverIsAvailable(this) { isServerAvailable ->
+                if (!isServerAvailable) {
+                    noInternetConnectionAvailableNotification(this)
+                } else {
+                    runOnUiThread {
+                        loadingDialog.show()
+                    }
+                    net.getGroupId(groupName, { requestGroupIdResponse ->
+                        var groupId: Int
+                        try {
+                            groupId = requestGroupIdResponse.toInt()
+                        } catch (e: Exception) {
+                            runOnUiThread {
+                                loadingDialog.dismiss()
+                                Toast.makeText(this, requestGroupIdResponse, Toast.LENGTH_SHORT).show()
+                            }
+                            return@getGroupId
+                        }
+                        net.joinGroup(groupId, groupPassword, { response ->
+                            val responseText = response.body!!.string()
 
-            if (response.code == 200) {
-                val currentGroups = sharedPreferences.getStringSet("groups", mutableSetOf())
-                currentGroups!!.add(groupId.toString())
-                sharedPreferences.edit().putStringSet("groups", currentGroups).apply()
-                sharedPreferences.edit().putString("currentGroup", groupId.toString()).apply()
-                val intent = Intent(this, MainActivity::class.java)
-                startActivity(intent)
-                finish()
-            } else {
-                Toast.makeText(this, responseText, Toast.LENGTH_LONG).show()
+                            if (response.code == 200) {
+                                val currentGroups = sharedPreferences.getStringSet("groups", mutableSetOf())
+                                currentGroups!!.add(groupId.toString())
+                                sharedPreferences.edit().putStringSet("groups", currentGroups).apply()
+                                sharedPreferences.edit().putString("currentGroup", groupId.toString()).apply()
+                                runOnUiThread {
+                                    val intent = Intent(this, MainActivity::class.java)
+                                    startActivity(intent)
+                                    loadingDialog.dismiss()
+                                    finish()
+                                }
+                            } else {
+                                runOnUiThread {
+                                    loadingDialog.dismiss()
+                                    Toast.makeText(this, responseText, Toast.LENGTH_LONG).show()
+                                }
+                            }
+                        })
+                    })
+                }
             }
         }
     }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/LoginActivity.kt

@@ -1,16 +1,16 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
+import android.app.ProgressDialog
 import android.content.Intent
 import android.os.Bundle
 import android.widget.ArrayAdapter
 import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.databinding.ActivityLoginBinding
-import org.foxarmy.barcodescannerforemployees.parseArray
+import org.foxarmy.barcodescannerforemployees.noInternetConnectionAvailableNotification
+import org.foxarmy.barcodescannerforemployees.parseIntArray
 import org.json.JSONObject
 
 class LoginActivity : AppCompatActivity() {
@@ -23,15 +23,14 @@ class LoginActivity : AppCompatActivity() {
         binding = ActivityLoginBinding.inflate(layoutInflater);
         setContentView(binding.root)
 
+        val loadingDialog = ProgressDialog(this)
+        loadingDialog.setMessage(getString(R.string.loading_please_wait))
+        loadingDialog.setCancelable(false)
+        loadingDialog.setTitle(getString(R.string.loading))
+
         fillUpLanguagesSpinner()
 
-        val sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        val sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         binding.loginButton.setOnClickListener {
             val server = binding.serverTextEdit.text.toString()
@@ -40,32 +39,49 @@ class LoginActivity : AppCompatActivity() {
             val language = resources.getStringArray(R.array.languages)[binding.languageSpinner.selectedItemPosition]
             sharedPreferences.edit().putString("language", language).apply()
 
-            val n = Net()
-            n.language = sharedPreferences.getString("language", "en-US")!!
-            n.server = server
+            val net = Net()
+            net.language = sharedPreferences.getString("language", "en-US")!!
+            net.server = server
 
-            val response = n.login(username, password)
-            val responseText = response.body!!.string()
-            if (response.code != 200) {
-                Toast.makeText(this, responseText, Toast.LENGTH_SHORT).show()
-            } else {
-                val json = JSONObject(responseText)
-                sharedPreferences.edit().putString("token", json["token"].toString()).apply()
-                n.token = json["token"].toString()
-                sharedPreferences.edit().putInt("userId", json["id"].toString().toInt()).apply()
-                sharedPreferences.edit().putString("server", server).apply()
+            net.serverIsAvailable(this, { isServerAvailable ->
+                if (!isServerAvailable) {
+                    noInternetConnectionAvailableNotification(this)
+                } else {
+                    runOnUiThread {
+                        loadingDialog.show()
+                    }
+                    net.login(username, password, { response ->
+                        val responseText = response.body!!.string()
+                        if (response.code != 200) {
+                            runOnUiThread {
+                                Toast.makeText(this, responseText, Toast.LENGTH_SHORT).show()
+                            }
+                        } else {
+                            val json = JSONObject(responseText)
+                            sharedPreferences.edit().putString("token", json["token"].toString()).apply()
+                            net.token = json["token"].toString()
+                            sharedPreferences.edit().putInt("userId", json["id"].toString().toInt()).apply()
+                            sharedPreferences.edit().putString("server", server).apply()
 
+                            net.getMyGroups({ response ->
+                                runOnUiThread {
+                                    loadingDialog.dismiss()
+                                }
+                                val r = response.body!!.string()
+                                if (r == "" || r == "[]") {
+                                    goToActivity("GroupActivity")
+                                }
+                                val myGroups = parseIntArray(r).map { a -> a.toString() }
 
-                val r = n.getMyGroups().body!!.string()
-                val myGroups = parseArray(r).map { a -> a.toString()}
+                                sharedPreferences.edit().putStringSet("groups", myGroups.toSet()).apply()
+                                sharedPreferences.edit().putString("currentGroup", myGroups[0]).apply()
 
-                sharedPreferences.edit().putStringSet("groups", myGroups.toSet()).apply()
-                sharedPreferences.edit().putString("currentGroup", myGroups[0]).apply()
-
-                val intent = Intent(this, MainActivity::class.java)
-                startActivity(intent)
-                finish()
-            }
+                                goToActivity("MainActivity")
+                            })
+                        }
+                    })
+                }
+            })
         }
 
         binding.registerButton.setOnClickListener {
@@ -76,31 +92,64 @@ class LoginActivity : AppCompatActivity() {
             sharedPreferences.edit().putString("language", language).apply()
             sharedPreferences.edit().putString("server", server).apply()
 
-            val n = Net()
-            n.language = language
-            n.server = server
-            val response = n.registerAccount(username, password);
-            val responseText = response.body!!.string()
-            if (response.code != 200) {
-                Toast.makeText(this, responseText, Toast.LENGTH_SHORT).show();
-            } else {
-                sharedPreferences.edit().putInt("userId", responseText.toInt()).apply()
-                val token = JSONObject(n.login(username, password).body!!.string())["token"].toString()
-                sharedPreferences.edit().putString("token", token).apply()
+            val net = Net()
+            net.language = language
+            net.server = server
 
-                sharedPreferences.edit().putString("server", server).apply()
-                val intent = Intent(this, GroupActivity::class.java)
-                startActivity(intent)
-                finish()
-            }
+            net.serverIsAvailable(this, {isServerAvailable ->
+                if (!isServerAvailable) {
+                    noInternetConnectionAvailableNotification(this)
+                } else {
+                    net.registerAccount(username, password, {response ->
+                        val responseText = response.body!!.string()
+                        if (response.code != 200) {
+                            Toast.makeText(this, responseText, Toast.LENGTH_SHORT).show();
+                        } else {
+                            sharedPreferences.edit().putInt("userId", responseText.toInt()).apply()
+                            net.login(username, password, {response ->
+                                val token = JSONObject(response.body!!.string())["token"].toString()
+                                sharedPreferences.edit().putString("token", token).apply()
+
+                                sharedPreferences.edit().putString("server", server).apply()
+                                runOnUiThread {
+                                    loadingDialog.dismiss()
+                                }
+                                goToActivity("GroupActivity")
+                            })
+                        }
+                    })
+                }
+            })
+        }
+
+        binding.offlineButton.setOnClickListener {
+            sharedPreferences.edit().putString("currentGroup", "offline").apply()
+            sharedPreferences.edit().putStringSet("groups", setOf("offline")).apply()
+
+            val intent = Intent(this, MainActivity::class.java)
+            startActivity(intent)
+            finish()
         }
     }
 
     private fun fillUpLanguagesSpinner() {
         val languages = resources.getStringArray(R.array.languages)
-        val arrayAdapter = ArrayAdapter(this, androidx.appcompat.R.layout.support_simple_spinner_dropdown_item, languages)
+        val arrayAdapter =
+            ArrayAdapter(this, androidx.appcompat.R.layout.support_simple_spinner_dropdown_item, languages)
         arrayAdapter.setDropDownViewResource(androidx.appcompat.R.layout.support_simple_spinner_dropdown_item)
         binding.languageSpinner.adapter = arrayAdapter
     }
 
+    private fun goToActivity(activityName: String) {
+        runOnUiThread {
+            val intent = Intent(this, when(activityName) {
+                "MainActivity" -> MainActivity::class.java
+                "GroupActivity" -> GroupActivity::class.java
+                "LoginActivity" -> LoginActivity::class.java
+                else -> LoginActivity::class.java
+            })
+            startActivity(intent)
+            finish()
+        }
+    }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/MainActivity.kt

@@ -1,25 +1,24 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
 import android.app.Activity
+import android.app.ProgressDialog
 import android.content.DialogInterface
 import android.content.Intent
+import android.content.SharedPreferences
 import android.os.Bundle
+import android.util.Log
 import android.view.Menu
 import android.view.MenuItem
+import android.widget.Toast
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.app.ActionBarDrawerToggle
 import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.content.ContextCompat
 import androidx.drawerlayout.widget.DrawerLayout
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import androidx.viewpager.widget.ViewPager
 import com.google.android.material.navigation.NavigationView
-import org.foxarmy.barcodescannerforemployees.Net
-import org.foxarmy.barcodescannerforemployees.R
-import org.foxarmy.barcodescannerforemployees.ViewPagerAdapter
-import org.foxarmy.barcodescannerforemployees.convertToUnixEpochTimestamp
+import org.foxarmy.barcodescannerforemployees.*
 import org.foxarmy.barcodescannerforemployees.database.AbstractProductDAO
 import org.foxarmy.barcodescannerforemployees.database.CategoryDAO
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
@@ -39,9 +38,17 @@ import java.io.File
 class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelectedListener {
 
     private lateinit var binding: ActivityMainBinding
-    lateinit var adapter: ViewPagerAdapter
-    var drawerLayout: DrawerLayout? = null
-    var actionBarDrawerToggle: ActionBarDrawerToggle? = null
+    private lateinit var adapter: ViewPagerAdapter
+    private var drawerLayout: DrawerLayout? = null
+    private var actionBarDrawerToggle: ActionBarDrawerToggle? = null
+    private lateinit var ws: WebSocketClient
+
+    var selectionMode = false
+    private var selectedAmount = 0
+
+    private lateinit var sharedPreferences: SharedPreferences
+
+    private lateinit var loadingDialog: ProgressDialog
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -49,10 +56,23 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
         binding = ActivityMainBinding.inflate(layoutInflater)
         setContentView(binding.root)
 
+        loadingDialog = ProgressDialog(this)
+        loadingDialog.setMessage(getString(R.string.loading_please_wait))
+        loadingDialog.setCancelable(false)
+        loadingDialog.setTitle(getString(R.string.loading))
+
+        sharedPreferences = getPreferences(this)
+
         setSupportActionBar(binding.toolbar)
         setupViewPager(binding.tabViewpager)
         binding.tabTablayout.setupWithViewPager(binding.tabViewpager)
 
+        binding.tabTablayout.setOnDragListener { _, _ ->
+            selectionMode = false
+            selectedAmount = 0
+            true
+        }
+
         drawerLayout = binding.drawerLayout
         actionBarDrawerToggle = ActionBarDrawerToggle(this, drawerLayout, R.string.nav_open, R.string.nav_close)
 
@@ -60,7 +80,6 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
         actionBarDrawerToggle!!.syncState()
         binding.navView.setNavigationItemSelectedListener(this)
 
-        // to make the Navigation drawer icon always appear on the action bar
         supportActionBar!!.setDisplayHomeAsUpEnabled(true)
 
         binding.expiryCalendarFab.setOnClickListener { _ ->
@@ -70,7 +89,7 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
             ContextCompat.startActivity(this, expiryCalendarIntent, extras)
         }
 
-        binding.newElementFab.setOnClickListener { view ->
+        binding.newElementFab.setOnClickListener { _ ->
             val currentPosition = binding.tabTablayout.selectedTabPosition
             val fragment = adapter.getItem(currentPosition)
 
@@ -78,8 +97,6 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
                 "StorageFragment" -> {
                     val addAbstractProductIntent = Intent(this, AddAbstractProductActivity::class.java)
                     val extras = Bundle()
-                    // I reuse the same stuff for editing and adding new product.
-                    // if abstractProduct == null, it means that we need to create new object
                     extras.putParcelable("abstractProduct", null)
                     extras.putString("action", "new")
                     addAbstractProductIntent.putExtras(extras)
@@ -104,19 +121,24 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
                 }
             }
         }
-        synchronize()
+        val net = Net()
+        net.server = sharedPreferences.getString("server", "")!!
+        val currentGroup = sharedPreferences.getString("currentGroup", "offline")!!
+        net.serverIsAvailable(this, {isServerAvailable ->
+            if ( currentGroup != "offline" && !isServerAvailable) {
+                runOnUiThread {
+                    noInternetConnectionAvailableNotification(this)
+                }
+            } else if (currentGroup != "offline" && isServerAvailable) {
+                synchronize()
+                ws = WebSocketClient(this, sharedPreferences.getString("server", "")!!)
+                val token = sharedPreferences.getString("token", "")!!
+                ws.connect(token, currentGroup)
+            }
+        })
     }
 
     private fun synchronize() {
-
-        val sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
-
         if (sharedPreferences.getString("currentGroup", "offline")!! == "offline") return
 
         val net = Net()
@@ -127,26 +149,27 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
 
         val currentGroup = sharedPreferences.getString("currentGroup", "")!!.toInt()
 
-        val data = JSONObject(net.synchronize(currentGroup).body!!.string())
+        net.synchronize(currentGroup, {response ->
+            val data = JSONObject(response.body!!.string())
 
-        val remoteAbstractProducts = data["abstract_products"] as JSONArray
-        val remoteProducts = data["products"] as JSONArray
-        val remoteCategories = data["categories"] as JSONArray
+            val remoteAbstractProducts = data["abstract_products"] as JSONArray
+            val remoteProducts = data["products"] as JSONArray
+            val remoteCategories = data["categories"] as JSONArray
 
-        val dbHelper = DBStorageController(this, sharedPreferences.getString("currentGroup", "")!!)
+            val dbHelper = DBStorageController(this, sharedPreferences.getString("currentGroup", "")!!)
 
-        val abstractProductDAO = AbstractProductDAO(dbHelper)
-        val productDAO = ProductDAO(dbHelper)
-        val categoryDAO = CategoryDAO(dbHelper)
+            val abstractProductDAO = AbstractProductDAO(dbHelper)
+            val productDAO = ProductDAO(dbHelper)
+            val categoryDAO = CategoryDAO(dbHelper)
 
-        val localAbstractProducts = abstractProductDAO.getSortedListOfAbstractProducts(0, "", arrayOf(""))
-        val localProducts = productDAO.getSortedListOfProducts(0, "", "")
-        val localCategories = categoryDAO.getAllCategories()
-
-        syncAbstractProducts(net, currentGroup, abstractProductDAO, remoteAbstractProducts, localAbstractProducts)
-        syncProducts(productDAO, remoteProducts, localProducts)
-        syncCategories(categoryDAO, remoteCategories, localCategories)
+            val localAbstractProducts = abstractProductDAO.getSortedListOfAbstractProducts(0, "", arrayOf(""))
+            val localProducts = productDAO.getSortedListOfProducts(0, "", "")
+            val localCategories = categoryDAO.getAllCategories()
 
+            syncAbstractProducts(net, currentGroup, abstractProductDAO, remoteAbstractProducts, localAbstractProducts)
+            syncProducts(productDAO, remoteProducts, localProducts)
+            syncCategories(categoryDAO, remoteCategories, localCategories)
+        })
     }
 
     private fun syncCategories(
@@ -194,15 +217,7 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
 
             if (categoryInRemoteDB != null && categoryInLocalDB != null) {
                 if (categoryInRemoteDB["hash"] != categoryInLocalDB.calculateHash()) {
-
-                    var updatedData: Category
-
-                    with(categoryInRemoteDB) {
-                        updatedData = Category(
-                            this["local_id"].toString().toInt(),
-                            this["name"].toString()
-                        )
-                    }
+                    val updatedData = Category.createFromJSON(categoryInRemoteDB)
 
                     categoryDAO.updateCategory(updatedData)
                 }
@@ -241,35 +256,14 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
             }
 
             if (productInLocalDB == null && remoteProduct != null) {
-                var newProduct: Product
-
-                with(remoteProduct) {
-                    newProduct = Product(
-                        this["local_id"].toString().toInt(),
-                        this["abstract_product_id"].toString().toInt(),
-                        this["amount"].toString().toInt(),
-                        convertToUnixEpochTimestamp(this["date_of_production"].toString()),
-                        convertToUnixEpochTimestamp(this["expiry_date"].toString())
-                    )
-                }
+                val newProduct = Product.createFromJSON(remoteProduct)
 
                 productDAO.insertNewProduct(newProduct)
             }
 
             if (productInRemoteDB != null && productInLocalDB != null) {
                 if (productInRemoteDB["hash"] != productInLocalDB.calculateHash()) {
-
-                    var updatedData: Product
-
-                    with(productInRemoteDB) {
-                        updatedData = Product(
-                            this["local_id"].toString().toInt(),
-                            this["abstract_product_id"].toString().toInt(),
-                            this["amount"].toString().toInt(),
-                            convertToUnixEpochTimestamp(this["date_of_production"].toString()),
-                            convertToUnixEpochTimestamp(this["expiry_date"].toString())
-                        )
-                    }
+                    val updatedData = Product.createFromJSON(productInRemoteDB)
 
                     productDAO.updateProduct(updatedData)
                 }
@@ -318,24 +312,11 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
                 val pictureFile =
                     File(picturesDir, "${remoteAbstractProduct["image_filename"]}.png")
                 val url = "https://${net.server}/api/abstractproduct/getImage/${currentGroup}/${localId}"
-                net.downloadImage(url, pictureFile)
-
-                var newAbstractProduct: AbstractProduct
-
-                with(remoteAbstractProduct) {
-                    newAbstractProduct = AbstractProduct(
-                        this["local_id"].toString().toInt(),
-                        this["barcode"].toString(),
-                        this["name"].toString(),
-                        this["net_weight"].toString().toDouble(),
-                        this["image_filename"].toString(),
-                        this["category"].toString().toInt(),
-                        this["unit"].toString().toInt()
-                    )
-                }
-
-                abstractProductDAO.addAbstractProduct(newAbstractProduct)
+                net.downloadImage(url, pictureFile, {
+                    val newAbstractProduct = AbstractProduct.createFromJSON(remoteAbstractProduct)
 
+                    abstractProductDAO.addAbstractProduct(newAbstractProduct)
+                })
             }
 
             if (abstractProductInRemoteDB != null && abstractProductInLocalDB != null) {
@@ -345,24 +326,11 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
                     val pictureFile =
                         File(File(filesDir, "pictures"), "${abstractProductInRemoteDB["image_filename"]}.png")
                     val url = "https://${net.server}/api/abstractproduct/getImage/${currentGroup}/${localId}"
-                    net.downloadImage(url, pictureFile)
+                    net.downloadImage(url, pictureFile, {
+                        val updatedData = AbstractProduct.createFromJSON(abstractProductInRemoteDB)
 
-                    var updatedData: AbstractProduct
-
-                    with(abstractProductInRemoteDB) {
-                        updatedData = AbstractProduct(
-                            this["local_id"].toString().toInt(),
-                            this["barcode"].toString(),
-                            this["name"].toString(),
-                            this["net_weight"].toString().toDouble(),
-                            this["image_filename"].toString(),
-                            this["category"].toString().toInt(),
-                            this["unit"].toString().toInt()
-                        )
-                    }
-
-
-                    abstractProductDAO.updateAbstractProduct(updatedData)
+                        abstractProductDAO.updateAbstractProduct(updatedData)
+                    })
                 }
             }
         }
@@ -376,6 +344,7 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
         adapter.addFragment(CategoriesFragment(), getString(R.string.categories_title))
 
         viewpager.adapter = adapter
+        viewpager.offscreenPageLimit = 3
     }
 
     override fun onCreateOptionsMenu(menu: Menu): Boolean {
@@ -384,22 +353,43 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
         return true
     }
 
+    private fun isOffline(): Boolean {
+        return sharedPreferences.getString("currentGroup", "") == "offline"
+    }
+
     override fun onNavigationItemSelected(item: MenuItem): Boolean {
         lateinit var intent: Intent
         when (item.itemId) {
             R.id.nav_account -> {
+                if (isOffline()) {
+                    Toast.makeText(this, getString(R.string.online_only_feature), Toast.LENGTH_SHORT).show()
+                    return false
+                }
                 intent = Intent(this, AccountSettingsActivity::class.java)
                 settingsActivityLauncher.launch(intent)
                 return true
             }
 
             R.id.nav_groups -> {
+                if (isOffline()) {
+                    Toast.makeText(this, getString(R.string.online_only_feature), Toast.LENGTH_SHORT).show()
+                    return false
+                }
                 intent = Intent(this, MyGroupsActivity::class.java)
             }
 
             R.id.nav_settings -> {
                 intent = Intent(this, SettingsActivity::class.java)
             }
+
+            R.id.nav_logout -> {
+                sharedPreferences.edit().putString("currentGroup", "").apply()
+                sharedPreferences.edit().putStringSet("groups", emptySet()).apply()
+                sharedPreferences.edit().putString("token", "").apply()
+                sharedPreferences.edit().putString("server", "").apply()
+
+                intent = Intent(this, LoginActivity::class.java)
+            }
         }
         startActivity(intent)
 
@@ -416,13 +406,19 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
     }
 
     fun updateAll() {
-        val storageFragment: StorageFragment = adapter.getItem(0) as StorageFragment
-        val shelfFragment: ShelfFragment = adapter.getItem(1) as ShelfFragment
-        val categoriesFragment: CategoriesFragment = adapter.getItem(2) as CategoriesFragment
+        runOnUiThread {
+            try {
+                val storageFragment: StorageFragment = adapter.getItem(0) as StorageFragment
+                val shelfFragment: ShelfFragment = adapter.getItem(1) as ShelfFragment
+                val categoriesFragment: CategoriesFragment = adapter.getItem(2) as CategoriesFragment
 
-        storageFragment.updateContent()
-        shelfFragment.updateContent()
-        categoriesFragment.updateContent()
+                storageFragment.updateContent()
+                shelfFragment.updateContent()
+                categoriesFragment.updateContent()
+            } catch (e:Exception) {
+                Log.e("BSFE/MainActivity", e.message!!)
+            }
+        }
     }
 
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
@@ -509,4 +505,17 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
         val storageFragment = fragment as StorageFragment
         storageFragment.filterByCategory(id)
     }
+
+    fun addSelection() {
+        selectionMode = true
+        selectedAmount ++
+    }
+
+    fun removeSelection() {
+        selectedAmount --
+        if (selectedAmount <= 0) {
+            selectedAmount = 0
+            selectionMode = false
+        }
+    }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/ManageGroupActivity.kt

@@ -1,19 +1,27 @@
 package org.foxarmy.barcodescannerforemployees.activities
 
 import android.content.Context
+import android.content.Intent
+import android.content.SharedPreferences
 import android.os.Bundle
 import android.view.View
+import android.widget.EditText
+import android.widget.PopupMenu
+import android.widget.Toast
+import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
+import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.databinding.ActivityManageGroupBinding
-import org.foxarmy.barcodescannerforemployees.parseArray
+import org.foxarmy.barcodescannerforemployees.parseIntArray
 import org.foxarmy.barcodescannerforemployees.views.GroupMemberView
 
-class ManageGroupActivity : AppCompatActivity(){
+class ManageGroupActivity : AppCompatActivity() {
     private lateinit var binding: ActivityManageGroupBinding
-    private var isAdmin: Boolean = true
+    private var isAdmin: Boolean = false
+    private lateinit var sharedPreferences: SharedPreferences
+    private lateinit var net: Net
+    private var groupId: Int = 0
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -21,56 +29,150 @@ class ManageGroupActivity : AppCompatActivity(){
         binding = ActivityManageGroupBinding.inflate(layoutInflater)
         setContentView(binding.root)
 
-        val groupId = intent.extras!!.getInt("groupId")
+        groupId = intent.extras!!.getInt("groupId")
 
-        val masterKeyAlias = MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC)
+        sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
-        val sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            masterKeyAlias,
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
-
-        val net = Net()
+        net = Net()
 
         net.token = sharedPreferences.getString("token", "")!!
         net.server = sharedPreferences.getString("server", "")!!
         net.language = sharedPreferences.getString("language", "en-US")!!
 
 
-        val users = parseArray(net.getUsersInGroup(groupId).body!!.string())
+        setUpMembers()
 
-        for (user in users) {
-            val groupMemberView = GroupMemberView(this, this as Context, net.getUsernameById(user).body!!.string(), user)
+        binding.renameButton.setOnClickListener {
+            val input = EditText(this)
+            AlertDialog.Builder(this)
+                .setTitle(getString(R.string.new_group_name))
+                .setView(input)
+                .setPositiveButton(getString(R.string.ok)) { _, _ ->
+                    val newName = input.text.toString()
+                    net.renameGroup(groupId, newName, { response ->
+                        runOnUiThread {
+                            Toast.makeText(this, response.body!!.string(), Toast.LENGTH_LONG).show()
+                        }
+                    })
 
-            binding.groupsContent.addView(groupMemberView)
+                }
+                .setNegativeButton(getString(R.string.cancel)) { _, _ ->
+
+                }.show()
         }
 
-        isAdmin = amIAnAdminIn(groupId)
+        binding.leaveButton.setOnClickListener {
+            net.leaveGroup(groupId, { response ->
+                runOnUiThread {
+                    Toast.makeText(this, response.body!!.string(), Toast.LENGTH_SHORT).show()
+                }
+                if (response.code == 200) {
+                    val groups = sharedPreferences.getStringSet("groups", emptySet())!!
+                    groups.remove(groupId.toString())
+                    sharedPreferences.edit().putStringSet("groups", groups).apply()
+                    sharedPreferences.edit().putString("currentGroup", "").apply()
 
-        if (!isAdmin) {
-            binding.renameButton.visibility = View.GONE
+                    if (groups.isEmpty()) {
+                        runOnUiThread {
+                            val intent = Intent(this, GroupActivity::class.java)
+                            startActivity(intent)
+                            finish()
+                        }
+                    }
+                    sharedPreferences.edit().putString("currentGroup", groups.toList()[0]).apply()
+                    runOnUiThread {
+                        finish()
+                    }
+                }
+            })
         }
+
+        setUpAdminRelatedButtons()
     }
 
-    fun amIAnAdminIn(groupId: Int): Boolean {
-        val sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+    private fun setUpMembers() {
+        net.getUsersInGroup(groupId, { response ->
+            val users = parseIntArray(response.body!!.string())
+            for (user in users) {
+                net.getUsernameById(user, { response ->
+                    val groupMemberView = GroupMemberView(this, this as Context, response.body!!.string(), user)
 
+                    groupMemberView.setOnLongClickListener { view ->
+                        amIAnAdminIn(groupId, { amIAnAdmin ->
+                            if (!amIAnAdmin) return@amIAnAdminIn
+                            runOnUiThread {
+                                val popupMenu = PopupMenu(this, groupMemberView)
+                                popupMenu.inflate(R.menu.user_pop_menu)
+                                popupMenu.setOnMenuItemClickListener { item ->
+                                    when (item.itemId) {
+                                        R.id.kick -> {
+
+                                            setUpMembers()
+                                            false
+                                        }
+
+                                        R.id.transfer_ownership -> {
+                                            AlertDialog.Builder(this)
+                                                .setMessage(getString(R.string.transfer_ownership_confirmation))
+                                                .setPositiveButton(R.string.yes) { _, _ ->
+                                                    net.transfer_ownership(
+                                                        groupId,
+                                                        (view as GroupMemberView).userId,
+                                                        { response ->
+                                                            runOnUiThread {
+                                                                Toast.makeText(
+                                                                    this,
+                                                                    response.body!!.string(),
+                                                                    Toast.LENGTH_SHORT
+                                                                ).show()
+                                                                setUpAdminRelatedButtons()
+                                                            }
+                                                        })
+
+                                                }
+                                                .setNegativeButton(R.string.no) { _, _ -> }
+                                                .show()
+                                            true
+                                        }
+
+                                        else -> false
+                                    }
+                                }
+                                runOnUiThread {
+                                    popupMenu.show()
+                                }
+                            }
+                        })
+                        true
+                    }
+                    runOnUiThread {
+                        binding.groupsContent.addView(groupMemberView)
+                    }
+                })
+            }
+        })
+    }
+
+    fun amIAnAdminIn(groupId: Int, callback: (Boolean) -> Unit) {
         val net = Net()
 
         net.token = sharedPreferences.getString("token", "")!!
         net.server = sharedPreferences.getString("server", "")!!
         net.language = sharedPreferences.getString("language", "en-US")!!
 
-        val result = sharedPreferences.getInt("userId", 0) == net.getGroupAdminId(groupId).body!!.string().toInt()
-        return result
+        net.getGroupAdminId(groupId, { response ->
+            val result = sharedPreferences.getInt("userId", 0) == response.body!!.string().toInt()
+            callback(result)
+        })
+    }
+
+    fun setUpAdminRelatedButtons() {
+        amIAnAdminIn(groupId, { isAdmin ->
+            runOnUiThread {
+                if (!isAdmin) {
+                    binding.renameButton.visibility = View.GONE
+                }
+            }
+        })
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/MyGroupsActivity.kt

@@ -5,12 +5,10 @@ import android.content.Intent
 import android.os.Bundle
 import android.widget.LinearLayout
 import androidx.appcompat.app.AppCompatActivity
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.databinding.ActivityMyGroupsBinding
-import org.foxarmy.barcodescannerforemployees.parseArray
+import org.foxarmy.barcodescannerforemployees.parseIntArray
 import org.foxarmy.barcodescannerforemployees.views.GroupView
 
 class MyGroupsActivity : AppCompatActivity(){
@@ -22,13 +20,7 @@ class MyGroupsActivity : AppCompatActivity(){
         binding = ActivityMyGroupsBinding.inflate(layoutInflater)
         setContentView(binding.root)
 
-        val sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        val sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         val net = Net()
 
@@ -36,20 +28,28 @@ class MyGroupsActivity : AppCompatActivity(){
         net.server = sharedPreferences.getString("server", "")!!
         net.language = sharedPreferences.getString("language", "en-US")!!
 
-        val groups = parseArray(net.getMyGroups().body!!.string())
-
-        val container = findViewById<LinearLayout>(R.id.groupsLayout)
-
-        for (group in groups) {
-            val groupView = GroupView(this, this as Context, net.getGroupName(group), group)
+        net.getMyGroups { response ->
+            val groups = parseIntArray(response.body!!.string())
 
 
-            container.addView(groupView)
-        }
+            val container = findViewById<LinearLayout>(R.id.groupsLayout)
 
-        binding.newGroup.setOnClickListener {
-            val intent = Intent(this, GroupActivity::class.java)
-            startActivity(intent)
+            for (group in groups) {
+                net.getGroupName(group, {response ->
+                    val groupView = GroupView(this, this as Context, response, group)
+
+                    runOnUiThread {
+                        container.addView(groupView)
+                    }
+                })
+            }
+
+            binding.newGroup.setOnClickListener {
+                runOnUiThread {
+                    val intent = Intent(this, GroupActivity::class.java)
+                    startActivity(intent)
+                }
+            }
         }
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/NavigatorActivity.kt

@@ -4,8 +4,8 @@ import android.app.Activity
 import android.content.Intent
 import android.content.SharedPreferences
 import android.os.Bundle
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
+import org.foxarmy.barcodescannerforemployees.Net
+import org.foxarmy.barcodescannerforemployees.parseStringList
 
 class NavigatorActivity : Activity() {
 
@@ -14,34 +14,55 @@ class NavigatorActivity : Activity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         var intent = Intent(this, MainActivity::class.java)
 
-        if (!isInGroup()) {
-            intent = Intent(this, GroupActivity::class.java)
+        isInGroup { flag ->
+            if (!flag && !isOffline()) {
+                intent = Intent(this, GroupActivity::class.java)
+            }
+            if (!isAuthenticated() && !isOffline()) {
+                intent = Intent(this, LoginActivity::class.java);
+            }
+
+            runOnUiThread {
+                startActivity(intent);
+                finish();
+            }
         }
+    }
 
-        if (!isAuthenticated()) {
-            intent = Intent(this, LoginActivity::class.java);
-        }
-
-
-        startActivity(intent);
-        finish();
+    private fun isOffline(): Boolean {
+        return sharedPreferences.getString("currentGroup", "")!! == "offline"
     }
 
     private fun isAuthenticated(): Boolean {
         return sharedPreferences.getString("token", "") != ""
     }
 
-    private fun isInGroup(): Boolean {
-        return sharedPreferences.getStringSet("groups", emptySet())!!.isNotEmpty()
+    private fun isInGroup(callback: (Boolean) -> Unit) {
+        val groups = sharedPreferences.getStringSet("groups", emptySet())!!
+        if (groups.isEmpty()) {
+            if (sharedPreferences.getString("token", "")!! == "") callback(false)
+            val net = Net()
+            net.language = sharedPreferences.getString("language", "")!!
+            net.server = sharedPreferences.getString("server", "")!!
+            net.token = sharedPreferences.getString("token", "")!!
+
+            net.getMyGroups { response ->
+                val responseBody = response.body!!.string()
+                if (responseBody == "" || responseBody == "[]") callback(false)
+                val groupsFromServer = parseStringList(responseBody)
+                if (groupsFromServer.isNotEmpty()) {
+                    sharedPreferences.edit().putStringSet("groups", groupsFromServer.toSet()).apply()
+                    sharedPreferences.edit().putString("currentGroup", groupsFromServer[0]).apply()
+                    callback(true)
+                } else {
+                    callback(false)
+                }
+            }
+        }
+        callback(true)
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/SettingsActivity.kt

@@ -6,8 +6,6 @@ import android.os.Bundle
 import android.view.View
 import android.widget.ArrayAdapter
 import androidx.appcompat.app.AppCompatActivity
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
 import org.foxarmy.barcodescannerforemployees.databinding.ActivitySettingsBinding
 
@@ -17,17 +15,12 @@ class SettingsActivity : AppCompatActivity() {
     lateinit var myGroups: List<String>
     lateinit var currentGroup: String
     lateinit var groupsNames: MutableList<String>
+    lateinit var namesMap: MutableMap<Int, String>
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            applicationContext,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = org.foxarmy.barcodescannerforemployees.getPreferences(this)
 
         myGroups = sharedPreferences.getStringSet("groups", emptySet())!!.toList()
         currentGroup = sharedPreferences.getString("currentGroup", "offline")!!
@@ -37,23 +30,35 @@ class SettingsActivity : AppCompatActivity() {
         net.language = sharedPreferences.getString("language", "")!!
         net.server = sharedPreferences.getString("server", "")!!
 
-        groupsNames = mutableListOf()
-
-        for (myGroup in myGroups) {
-            groupsNames.add(net.getGroupName(myGroup.toInt()))
-        }
-
         binding = ActivitySettingsBinding.inflate(layoutInflater)
         setContentView(binding.root)
 
         setUpImageCompressionSeekBar()
-        fillUpCurrentGroupSpinner()
+
+
+        if (isOffline()) {
+            binding.currentGroupSetting.visibility = View.GONE
+        } else {
+            namesMap = mutableMapOf()
+
+            for (myGroup in myGroups) {
+                net.getGroupName(myGroup.toInt(), { name ->
+                    namesMap[myGroup.toInt()] = name
+                    fillUpCurrentGroupSpinner()
+                })
+            }
+        }
 
         binding.saveButton.setOnClickListener {
-            sharedPreferences.edit().putString("currentGroup", net.getGroupId(binding.currentGroupSpinner.selectedItem.toString())).apply()
-            sharedPreferences.edit().putInt("imageCompression", binding.imageCompressionFactorSeekBar.progress + 1).apply()
-            setResult(Activity.RESULT_OK)
-            finish()
+            net.getGroupId(binding.currentGroupSpinner.selectedItem.toString(), { groupId ->
+                sharedPreferences.edit().putString("currentGroup", groupId).apply()
+                sharedPreferences.edit().putInt("imageCompression", binding.imageCompressionFactorSeekBar.progress + 1)
+                    .apply()
+                runOnUiThread {
+                    setResult(Activity.RESULT_OK)
+                    finish()
+                }
+            })
         }
 
         binding.cancelButton.setOnClickListener {
@@ -62,22 +67,37 @@ class SettingsActivity : AppCompatActivity() {
         }
     }
 
+    private fun isOffline(): Boolean {
+        return sharedPreferences.getString("currentGroup", "offline") == "offline"
+    }
+
     private fun setUpImageCompressionSeekBar() {
         val compressionFactor = sharedPreferences.getInt("imageCompression", 1)
         binding.imageCompressionFactorSeekBar.progress = compressionFactor - 1
     }
 
     private fun fillUpCurrentGroupSpinner() {
+        runOnUiThread {
+            if (currentGroup == "offline") {
+                binding.currentGroupSetting.visibility = View.GONE
+            }
+            groupsNames = mutableListOf()
+            groupsNames.clear()
+            val sortedMap = namesMap.entries.sortedBy { it.key }.associate { it.toPair() }
+            for ((id, name) in sortedMap) {
+                groupsNames.add(name)
+            }
 
-
-        if (currentGroup == "offline") {
-            binding.currentGroupSetting.visibility = View.GONE
+            val arrayAdapter =
+                ArrayAdapter(this, androidx.appcompat.R.layout.support_simple_spinner_dropdown_item, groupsNames)
+            arrayAdapter.setDropDownViewResource(androidx.appcompat.R.layout.support_simple_spinner_dropdown_item)
+            binding.currentGroupSpinner.adapter = arrayAdapter
+            if (myGroups.indexOf(currentGroup) < groupsNames.size) binding.currentGroupSpinner.setSelection(
+                myGroups.indexOf(
+                    currentGroup
+                )
+            )
         }
 
-        val arrayAdapter =
-            ArrayAdapter(this, androidx.appcompat.R.layout.support_simple_spinner_dropdown_item, groupsNames)
-        arrayAdapter.setDropDownViewResource(androidx.appcompat.R.layout.support_simple_spinner_dropdown_item)
-        binding.currentGroupSpinner.adapter = arrayAdapter
-        binding.currentGroupSpinner.setSelection(myGroups.indexOf(currentGroup))
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/database/AbstractProductDAO.kt

@@ -163,7 +163,7 @@ class AbstractProductDAO(private val dbHelper: DBStorageController) {
 
         with(cursor) {
             while (moveToNext()) {
-                val id = getInt(getColumnIndexOrThrow(android.provider.BaseColumns._ID))
+                val id = getInt(getColumnIndexOrThrow(BaseColumns._ID))
                 val productName =
                     getString(getColumnIndexOrThrow(AbstractProductContract.AbstractProductEntry.PRODUCT_NAME))
                 val imageFilename =
@@ -308,7 +308,7 @@ class AbstractProductDAO(private val dbHelper: DBStorageController) {
             }
 
             "barcodeless" -> {
-                selection = "${AbstractProductContract.AbstractProductEntry.BARCODE} = ? OR ${AbstractProductContract.AbstractProductEntry.BARCODE} = ?"
+                selection = "${AbstractProductContract.AbstractProductEntry.BARCODE} = ? OR ${AbstractProductContract.AbstractProductEntry.BARCODE} = ? OR ${AbstractProductContract.AbstractProductEntry.BARCODE} = ?"
                 selectionArgs = filter
             }
         }

app/src/main/java/org/foxarmy/barcodescannerforemployees/dataclasses/AbstractProduct.kt

@@ -3,6 +3,7 @@ package org.foxarmy.barcodescannerforemployees.dataclasses
 import android.os.Parcel
 import android.os.Parcelable
 import org.foxarmy.barcodescannerforemployees.md5
+import org.json.JSONObject
 
 class AbstractProduct() : Parcelable {
     var id: Int = 0
@@ -59,5 +60,17 @@ class AbstractProduct() : Parcelable {
         override fun newArray(size: Int): Array<AbstractProduct?> {
             return arrayOfNulls(size)
         }
+
+        fun createFromJSON(json: JSONObject): AbstractProduct {
+            return AbstractProduct(
+                json["local_id"].toString().toInt(),
+                json["barcode"].toString(),
+                json["name"].toString(),
+                json["net_weight"].toString().toDouble(),
+                json["image_filename"].toString(),
+                json["category"].toString().toInt(),
+                json["unit"].toString().toInt()
+            )
+        }
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/dataclasses/Category.kt

@@ -3,6 +3,7 @@ package org.foxarmy.barcodescannerforemployees.dataclasses
 import android.os.Parcel
 import android.os.Parcelable
 import org.foxarmy.barcodescannerforemployees.md5
+import org.json.JSONObject
 
 class Category() : Parcelable {
     var id = 0
@@ -40,5 +41,12 @@ class Category() : Parcelable {
         override fun newArray(size: Int): Array<Category?> {
             return arrayOfNulls(size)
         }
+
+        fun createFromJSON(json: JSONObject): Category {
+            return Category(
+                json["local_id"].toString().toInt(),
+                json["name"].toString()
+            )
+        }
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/dataclasses/Product.kt

@@ -5,7 +5,9 @@ import android.os.Parcel
 import android.os.Parcelable
 import androidx.annotation.RequiresApi
 import org.foxarmy.barcodescannerforemployees.calculateProductFreshness
+import org.foxarmy.barcodescannerforemployees.convertToUnixEpochTimestamp
 import org.foxarmy.barcodescannerforemployees.md5
+import org.json.JSONObject
 
 class Product() : Parcelable {
     var id = 0
@@ -59,5 +61,16 @@ class Product() : Parcelable {
         override fun newArray(size: Int): Array<Product?> {
             return arrayOfNulls(size)
         }
+
+        @RequiresApi(Build.VERSION_CODES.O)
+        fun createFromJSON(json: JSONObject): Product {
+            return Product(
+                json["local_id"].toString().toInt(),
+                json["abstract_product_id"].toString().toInt(),
+                json["amount"].toString().toInt(),
+                convertToUnixEpochTimestamp(json["date_of_production"].toString()),
+                convertToUnixEpochTimestamp(json["expiry_date"].toString())
+            )
+        }
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/fragments/CategoriesFragment.kt

@@ -11,36 +11,31 @@ import android.widget.Toast
 import androidx.core.content.ContextCompat
 import androidx.core.view.children
 import androidx.fragment.app.Fragment
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.activities.AddCategoryActivity
 import org.foxarmy.barcodescannerforemployees.database.CategoryDAO
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
+import org.foxarmy.barcodescannerforemployees.getPreferences
 import org.foxarmy.barcodescannerforemployees.views.CategoryView
+import kotlin.concurrent.thread
 
 class CategoriesFragment : Fragment() {
 
     private lateinit var sharedPreferences: SharedPreferences
     private lateinit var categoryDAO: CategoryDAO
+    private var updateInProgress = false
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            requireContext(),
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(requireContext())
 
         prepareDatabaseConnection()
     }
 
     private fun prepareDatabaseConnection() {
-        val dbHelper = DBStorageController(requireContext(), sharedPreferences.getString("currentGroup", "database")!!)
+        val dbHelper = DBStorageController(requireContext(), sharedPreferences.getString("currentGroup", "offline")!!)
         categoryDAO = CategoryDAO(dbHelper)
     }
 
@@ -58,56 +53,75 @@ class CategoriesFragment : Fragment() {
     }
 
     fun removeSelected() {
-        val layout = view?.findViewById<LinearLayout>(R.id.categoriesLayout)
+        thread {
+            val layout = view?.findViewById<LinearLayout>(R.id.categoriesLayout)
 
-        var deleted = false
-        for (view: CategoryView in layout?.children!!.iterator() as Iterator<CategoryView>) {
-            if (view.isCategorySelected) {
-                val net = Net()
-                net.token = sharedPreferences.getString("token", "")!!
-                net.server = sharedPreferences.getString("server", "")!!
-                net.language = sharedPreferences.getString("language", "en-US")!!
-                val currentGroup = sharedPreferences.getString("currentGroup", "")!!.toInt()
+            var deleted = false
+            for (view: CategoryView in layout?.children!!.iterator() as Iterator<CategoryView>) {
+                if (view.isCategorySelected) {
+                    val net = Net()
+                    net.token = sharedPreferences.getString("token", "")!!
+                    net.server = sharedPreferences.getString("server", "")!!
+                    net.language = sharedPreferences.getString("language", "en-US")!!
+                    val currentGroup = sharedPreferences.getString("currentGroup", "")!!.toInt()
 
-                categoryDAO.eraseCategory(view.category.id, requireContext())
-                val response = net.deleteCategory(currentGroup, view.category.id)
-                activity!!.runOnUiThread{
-                    Toast.makeText(context, response.body!!.string(), Toast.LENGTH_SHORT).show()
+                    categoryDAO.eraseCategory(view.category.id, requireContext())
+                    net.deleteCategory(currentGroup, view.category.id, {response ->
+                        activity!!.runOnUiThread{
+                            Toast.makeText(context, response.body!!.string(), Toast.LENGTH_SHORT).show()
+                        }
+
+                    })
+                    deleted = true
                 }
-
-                deleted = true
             }
-        }
 
-        if (!deleted) {
-            Toast.makeText(requireContext(), getString(R.string.nothing_to_delete), Toast.LENGTH_SHORT).show()
+            if (!deleted) {
+                activity!!.runOnUiThread {
+                    Toast.makeText(requireContext(), getString(R.string.nothing_to_delete), Toast.LENGTH_SHORT).show()
+                }
+            }
+            updateContent()
         }
-        updateContent()
     }
 
     fun updateSelected() {
-        val layout = view?.findViewById<LinearLayout>(R.id.categoriesLayout)
-        for (view: CategoryView in layout?.children!!.iterator() as Iterator<CategoryView>) {
-            if (view.isCategorySelected) {
-                val addCategoryIntent = Intent(context, AddCategoryActivity::class.java)
-                val extras = Bundle()
-                extras.putParcelable("category", view.category)
-                addCategoryIntent.putExtras(extras)
-                ContextCompat.startActivity(context!!, addCategoryIntent, extras)
+        thread {
+            val layout = view?.findViewById<LinearLayout>(R.id.categoriesLayout)
+            for (view: CategoryView in layout?.children!!.iterator() as Iterator<CategoryView>) {
+                if (view.isCategorySelected) {
+                    val addCategoryIntent = Intent(context, AddCategoryActivity::class.java)
+                    val extras = Bundle()
+                    extras.putParcelable("category", view.category)
+                    addCategoryIntent.putExtras(extras)
+                    activity!!.runOnUiThread {
+                        ContextCompat.startActivity(context!!, addCategoryIntent, extras)
+                    }
+                }
             }
         }
     }
 
     fun updateContent() {
-        prepareDatabaseConnection()
-        val layout = view?.findViewById<LinearLayout>(R.id.categoriesLayout)
-        layout?.removeAllViews()
+        thread {
+            if (updateInProgress) return@thread
+            updateInProgress = true
+            prepareDatabaseConnection()
+            val layout = view?.findViewById<LinearLayout>(R.id.categoriesLayout)
+            activity!!.runOnUiThread {
+                layout?.removeAllViews()
+            }
 
-        val categories = categoryDAO.getAllCategories()
+            val categories = categoryDAO.getAllCategories()
 
-        for (category in categories) {
-            val categoryView = CategoryView(requireActivity(), requireContext(), category)
-            layout?.addView(categoryView)
+            for (category in categories) {
+                val categoryView = CategoryView(requireActivity(), requireContext(), category)
+                activity!!.runOnUiThread {
+                    layout?.addView(categoryView)
+                }
+            }
+
+            updateInProgress = false
         }
     }
 

app/src/main/java/org/foxarmy/barcodescannerforemployees/fragments/ShelfFragment.kt

@@ -14,14 +14,13 @@ import androidx.core.content.ContextCompat
 import androidx.core.view.children
 import androidx.fragment.app.Fragment
 import androidx.gridlayout.widget.GridLayout
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.activities.AddProductActivity
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
 import org.foxarmy.barcodescannerforemployees.database.ProductDAO
 import org.foxarmy.barcodescannerforemployees.databinding.FragmentShelfBinding
+import org.foxarmy.barcodescannerforemployees.getPreferences
 import org.foxarmy.barcodescannerforemployees.views.ProductView
 import kotlin.concurrent.thread
 
@@ -38,16 +37,9 @@ class ShelfFragment : Fragment() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            requireContext(),
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(requireContext())
 
         prepareDatabaseConnection()
-
     }
 
     override fun onCreateView(
@@ -122,11 +114,12 @@ class ShelfFragment : Fragment() {
     }
 
     fun updateContent() {
-        prepareDatabaseConnection()
         thread {
             if (updateInProgress) return@thread
             updateInProgress = true
+            prepareDatabaseConnection()
             val grv = view?.findViewById<GridLayout>(R.id.contentGridLayout)
+
             activity!!.runOnUiThread {
                 grv?.removeAllViews()
             }
@@ -144,7 +137,6 @@ class ShelfFragment : Fragment() {
                 }
             }
             updateInProgress = false
-
         }
     }
 
@@ -165,11 +157,12 @@ class ShelfFragment : Fragment() {
                     val currentGroup = sharedPreferences.getString("currentGroup", "")!!.toInt()
 
                     productDAO.eraseProduct(view.product.id)
-                    val response = net.deleteProduct(currentGroup, view.product.id)
-                    activity!!.runOnUiThread{
-                        Toast.makeText(context, response.body!!.string(), Toast.LENGTH_SHORT).show()
-                    }
-
+                    net.deleteProduct(currentGroup, view.product.id, {response ->
+                        activity!!.runOnUiThread{
+                            Toast.makeText(context, response.body!!.string(), Toast.LENGTH_SHORT).show()
+                        }
+                    })
+                    
                     deleted = true
                 }
             }

app/src/main/java/org/foxarmy/barcodescannerforemployees/fragments/StorageFragment.kt

@@ -7,11 +7,10 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import android.widget.*
+import androidx.constraintlayout.widget.ConstraintLayout
 import androidx.core.content.ContextCompat
 import androidx.core.view.children
 import androidx.fragment.app.Fragment
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.Net
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.activities.AddAbstractProductActivity
@@ -20,6 +19,7 @@ import org.foxarmy.barcodescannerforemployees.database.AbstractProductDAO
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
 import org.foxarmy.barcodescannerforemployees.databinding.FragmentStorageBinding
 import org.foxarmy.barcodescannerforemployees.generateThumbnailForImage
+import org.foxarmy.barcodescannerforemployees.getPreferences
 import org.foxarmy.barcodescannerforemployees.views.AbstractProductView
 import kotlin.concurrent.thread
 
@@ -32,23 +32,18 @@ class StorageFragment : Fragment() {
     private lateinit var sharedPreferences: SharedPreferences
     private lateinit var abstractProductDAO: AbstractProductDAO
 
+    private var updateInProcess = false
 
     override fun onCreateView(
         inflater: LayoutInflater, container: ViewGroup?,
         savedInstanceState: Bundle?
     ): View {
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            requireContext(),
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        binding = FragmentStorageBinding.inflate(inflater)
+
+        sharedPreferences = getPreferences(requireContext())
 
         prepareDatabaseConnection()
 
-        binding = FragmentStorageBinding.inflate(inflater)
-
         fillUpSortBySpinner()
 
         binding.spinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
@@ -107,10 +102,12 @@ class StorageFragment : Fragment() {
                     val currentGroup = sharedPreferences.getString("currentGroup", "")!!.toInt()
 
                     abstractProductDAO.eraseAbstractProduct(view.abstractProduct.id, requireContext())
-                    val response = net.deleteAbstractProduct(currentGroup, view.abstractProduct.id)
-                    activity!!.runOnUiThread{
-                        Toast.makeText(context, response.body!!.string(), Toast.LENGTH_SHORT).show()
-                    }
+                    net.deleteAbstractProduct(currentGroup, view.abstractProduct.id, {response ->
+                        activity!!.runOnUiThread{
+                            Toast.makeText(context, response.body!!.string(), Toast.LENGTH_SHORT).show()
+                        }
+                    })
+
 
                     deleted = true
                 }
@@ -141,10 +138,14 @@ class StorageFragment : Fragment() {
     }
 
     fun updateContent() {
-        prepareDatabaseConnection()
         thread {
+            if (updateInProcess) return@thread
+            updateInProcess = true
+            prepareDatabaseConnection()
+
             val grv = binding.contentGridLayout
-            activity!!.runOnUiThread{
+
+            activity!!.runOnUiThread {
                 grv.removeAllViews()
             }
 
@@ -160,11 +161,25 @@ class StorageFragment : Fragment() {
                 )
 
                 if (filterBy == "barcodeless") {
-                    abstractProductView.setOnClickListener {
-                        (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
-                    }
-                    abstractProductView.findViewById<TextView>(R.id.productNameView).setOnClickListener {
-                        (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
+                    abstractProductView.also {
+                        it.setOnClickListener {
+                            (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
+                        }
+                        it.findViewById<TextView>(R.id.productNameView).setOnClickListener {
+                            (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
+                        }
+                        it.findViewById<ConstraintLayout>(R.id.productLayout).setOnClickListener {
+                            (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
+                        }
+                        it.findViewById<TextView>(R.id.categoryView).setOnClickListener {
+                            (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
+                        }
+                        it.findViewById<TextView>(R.id.unitView).setOnClickListener {
+                            (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
+                        }
+                        it.findViewById<TextView>(R.id.productNetWeightView).setOnClickListener {
+                            (activity as FindBarcodelessAbstractProduct).selected(abstractProductView.abstractProduct)
+                        }
                     }
                 }
 
@@ -172,14 +187,10 @@ class StorageFragment : Fragment() {
                     grv.addView(abstractProductView)
                 }
             }
-        }.join()
+            updateInProcess = false
+        }
     }
 
-    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
-        super.onViewCreated(view, savedInstanceState)
-
-        updateContent()
-    }
 
     fun filterByCategory(id: Int) {
         filterBy = "category"
@@ -194,7 +205,7 @@ class StorageFragment : Fragment() {
             val args = Bundle()
             args.putString("filterBy", filterBy)
             args.putStringArray("filter", filter)
-            fragment.setArguments(args)
+            fragment.arguments = args
 
             return fragment
         }

app/src/main/java/org/foxarmy/barcodescannerforemployees/views/AbstractProductView.kt

@@ -14,19 +14,15 @@ import android.widget.Toast
 import androidx.constraintlayout.widget.ConstraintLayout
 import androidx.core.content.ContextCompat
 import androidx.core.content.ContextCompat.startActivity
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
-import org.foxarmy.barcodescannerforemployees.R
+import org.foxarmy.barcodescannerforemployees.*
 import org.foxarmy.barcodescannerforemployees.activities.FullscreenActivity
+import org.foxarmy.barcodescannerforemployees.activities.MainActivity
 import org.foxarmy.barcodescannerforemployees.database.CategoryDAO
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
 import org.foxarmy.barcodescannerforemployees.dataclasses.AbstractProduct
-import org.foxarmy.barcodescannerforemployees.getActivity
-import org.foxarmy.barcodescannerforemployees.getImageUri
-import org.foxarmy.barcodescannerforemployees.getUnitNameById
 import java.io.File
 
-class AbstractProductView: LinearLayout {
+class AbstractProductView : LinearLayout {
     private var productLayout: ConstraintLayout? = null
     private var productPicture: ImageView? = null
     private var productNameField: TextView? = null
@@ -42,16 +38,10 @@ class AbstractProductView: LinearLayout {
 
     constructor(context: Context, a: AttributeSet) : super(context, a) {
         activity = getActivity(context)!!
-        val inflater:LayoutInflater = activity.layoutInflater
+        val inflater: LayoutInflater = activity.layoutInflater
         inflater.inflate(R.layout.abstract_product_view, this)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            context,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(context)
 
         val dbHelper = DBStorageController(context, sharedPreferences.getString("currentGroup", "database")!!)
         categoryDAO = CategoryDAO(dbHelper)
@@ -60,23 +50,17 @@ class AbstractProductView: LinearLayout {
     constructor(activity: Activity, context: Context, abstractProduct: AbstractProduct) : super(context) {
         this.abstractProduct = abstractProduct
         this.activity = activity
-        val inflater:LayoutInflater = activity.layoutInflater
+        val inflater: LayoutInflater = activity.layoutInflater
         inflater.inflate(R.layout.abstract_product_view, this)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            context,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(context)
 
         val dbHelper = DBStorageController(context, sharedPreferences.getString("currentGroup", "database")!!)
         categoryDAO = CategoryDAO(dbHelper)
         update()
     }
 
-    fun init () {
+    private fun init() {
         productLayout = findViewById(R.id.productLayout)
         productPicture = findViewById(R.id.productPicture)
         productNameField = findViewById(R.id.productNameView)
@@ -84,30 +68,8 @@ class AbstractProductView: LinearLayout {
         categoryField = findViewById(R.id.categoryView)
         unitField = findViewById(R.id.unitView)
 
-
-        productPicture!!.setOnClickListener {
-            val fullscreenIntent = Intent(activity, FullscreenActivity::class.java)
-            val extras = Bundle()
-            extras.putString("imagehash", abstractProduct.imageHash)
-            fullscreenIntent.putExtras(extras)
-            startActivity(context, fullscreenIntent, extras)
-        }
-
-        productLayout!!.setOnClickListener {
-
-        }
-
+        setUpClicks()
         unitField?.text = getUnitNameById(context, abstractProduct.unit)
-
-        productLayout!!.setOnLongClickListener {
-            isProductSelected = !isProductSelected
-            this.background = ContextCompat.getDrawable(context, if (isProductSelected) R.drawable.outline_selected else R.drawable.outline)
-            true
-        }
-
-        productNameField!!.setOnClickListener {
-            Toast.makeText(activity, productNameField!!.text, Toast.LENGTH_SHORT).show()
-        }
     }
 
     fun update() {
@@ -117,10 +79,126 @@ class AbstractProductView: LinearLayout {
         thumbnailsDir.mkdirs()
         val imageUri = getImageUri(activity, File(thumbnailsDir, "${abstractProduct.imageHash}.webp"))
         productPicture!!.setImageURI(imageUri)
-//        productPicture!!.rotation = 90f
 
         productNameField!!.text = abstractProduct.name
         netWeightField!!.text = abstractProduct.netWeight.toString()
         categoryField!!.text = categoryDAO.getCategoryNameById(abstractProduct.category)
     }
+
+
+    private fun setUpClicks() {
+        productLayout!!.setOnLongClickListener { onAnyLongClick() }
+        productNameField!!.setOnLongClickListener { onNameLongClick() }
+        productPicture!!.setOnLongClickListener { onImageLongClick() }
+        netWeightField!!.setOnLongClickListener { onAnyLongClick() }
+        categoryField!!.setOnLongClickListener { onAnyLongClick() }
+        unitField!!.setOnLongClickListener { onAnyLongClick() }
+
+        productLayout!!.setOnClickListener { onAnyClick() }
+        netWeightField!!.setOnClickListener { onAnyClick() }
+        categoryField!!.setOnClickListener { onAnyClick() }
+        unitField!!.setOnClickListener { onAnyClick() }
+        productPicture!!.setOnClickListener { onImageLongClick() }
+        productNameField!!.setOnClickListener { onNameLongClick() }
+    }
+
+    private fun onAnyClick(): Boolean {
+        if (activity !is MainActivity) return false
+        val mainActivity = activity as MainActivity
+
+        if (mainActivity.selectionMode) {
+            isProductSelected = !isProductSelected
+
+            if (isProductSelected) {
+                mainActivity.addSelection()
+            } else {
+                mainActivity.removeSelection()
+            }
+            activity.runOnUiThread {
+                this.background = ContextCompat.getDrawable(
+                    context,
+                    if (isProductSelected) R.drawable.outline_selected else R.drawable.outline
+                )
+            }
+            return true
+        } else {
+            return false
+        }
+    }
+
+    private fun onAnyLongClick(): Boolean {
+        if (activity !is MainActivity) return false
+        val mainActivity = activity as MainActivity
+
+        if (mainActivity.selectionMode) {
+            isProductSelected = !isProductSelected
+
+            if (isProductSelected) {
+                mainActivity.addSelection()
+            } else {
+                mainActivity.removeSelection()
+            }
+            activity.runOnUiThread {
+                this.background = ContextCompat.getDrawable(
+                    context,
+                    if (isProductSelected) R.drawable.outline_selected else R.drawable.outline
+                )
+            }
+            return true
+        } else {
+            mainActivity.addSelection()
+
+            isProductSelected = !isProductSelected
+            activity.runOnUiThread {
+
+                this.background = ContextCompat.getDrawable(
+                    context,
+                    if (isProductSelected) R.drawable.outline_selected else R.drawable.outline
+                )
+            }
+            return true
+        }
+    }
+
+    private fun onImageLongClick(): Boolean {
+        if (activity !is MainActivity) {
+            val fullscreenIntent = Intent(activity, FullscreenActivity::class.java)
+            val extras = Bundle()
+            extras.putString("imagehash", abstractProduct.imageHash)
+            fullscreenIntent.putExtras(extras)
+            startActivity(context, fullscreenIntent, extras)
+            return true
+        }
+        val mainActivity = activity as MainActivity
+
+        if (mainActivity.selectionMode) {
+            return onAnyLongClick()
+        } else {
+            val fullscreenIntent = Intent(activity, FullscreenActivity::class.java)
+            val extras = Bundle()
+            extras.putString("imagehash", abstractProduct.imageHash)
+            fullscreenIntent.putExtras(extras)
+            startActivity(context, fullscreenIntent, extras)
+        }
+        return true
+    }
+
+    private fun onNameLongClick(): Boolean {
+        if (activity !is MainActivity) {
+            activity.runOnUiThread {
+                Toast.makeText(activity, productNameField!!.text, Toast.LENGTH_SHORT).show()
+            }
+            return true
+        }
+        val mainActivity = activity as MainActivity
+
+        if (mainActivity.selectionMode) {
+            return onAnyLongClick()
+        } else {
+            activity.runOnUiThread {
+                Toast.makeText(activity, productNameField!!.text, Toast.LENGTH_SHORT).show()
+            }
+        }
+        return true
+    }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/views/CategoryView.kt

@@ -7,16 +7,16 @@ import android.view.LayoutInflater
 import android.widget.LinearLayout
 import android.widget.TextView
 import androidx.core.content.ContextCompat
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.activities.MainActivity
 import org.foxarmy.barcodescannerforemployees.database.AbstractProductDAO
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
 import org.foxarmy.barcodescannerforemployees.dataclasses.Category
+import org.foxarmy.barcodescannerforemployees.getPreferences
 
 class CategoryView : LinearLayout {
     var category: Category
+
     val categoryName: TextView
     val amountOfProducts: TextView
     var isCategorySelected = false
@@ -27,13 +27,7 @@ class CategoryView : LinearLayout {
     constructor(activity: Activity, context: Context, category: Category) : super(context) {
         this.category = category
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            context,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(context)
 
         val dbHelper = DBStorageController(context, sharedPreferences.getString("currentGroup", "database")!!)
         abstractProductDAO = AbstractProductDAO(dbHelper)
@@ -41,7 +35,7 @@ class CategoryView : LinearLayout {
         val inflater: LayoutInflater = activity.layoutInflater
         inflater.inflate(R.layout.category_view, this)
 
-        this.background = ContextCompat.getDrawable(context, if (isCategorySelected) R.drawable.outline_selected else R.drawable.outline)
+        updateStroke()
 
         categoryName = findViewById(R.id.categoryNameTextView)
         amountOfProducts = findViewById(R.id.amountOfProducts)
@@ -49,13 +43,47 @@ class CategoryView : LinearLayout {
         categoryName.text = category.name
         amountOfProducts.text = abstractProductDAO.getAmountOfAbstractProductsInCategory(category.id).toString()
 
-        setOnLongClickListener {
-            isCategorySelected = !isCategorySelected
-            this.background = ContextCompat.getDrawable(context, if (isCategorySelected) R.drawable.outline_selected else R.drawable.outline)
-            true
+        setUpClicks()
+    }
+
+    private fun setUpClicks() {
+        categoryName.setOnClickListener { onCategoryClick() }
+        amountOfProducts.setOnClickListener { onCategoryClick() }
+
+        categoryName.setOnLongClickListener { onAnyLongClick() }
+        amountOfProducts.setOnLongClickListener { onAnyLongClick() }
+    }
+
+    private fun onCategoryClick(): Boolean {
+        if (context !is MainActivity) return false
+        val mainActivity = context as MainActivity
+
+        if (mainActivity.selectionMode) return onAnyLongClick()
+        else (context as MainActivity).filterAbstractProductsByCategory(category.id)
+
+        return true
+    }
+
+    private fun onAnyLongClick(): Boolean {
+        if (context !is MainActivity) return false
+        val mainActivity = context as MainActivity
+
+        isCategorySelected = !isCategorySelected
+        updateStroke()
+
+        if (mainActivity.selectionMode) {
+            if (isCategorySelected) mainActivity.addSelection()
+            else mainActivity.removeSelection()
+        } else {
+            mainActivity.addSelection()
         }
-        setOnClickListener {
-            (activity as MainActivity).filterAbstractProductsByCategory(category.id)
+        return true
+
+    }
+
+    private fun updateStroke() {
+        (context as Activity).runOnUiThread {
+            this.background = ContextCompat.getDrawable(context, if (isCategorySelected) R.drawable.outline_selected else R.drawable.outline)
         }
     }
 }

app/src/main/java/org/foxarmy/barcodescannerforemployees/views/ExpiryGroupView.kt

@@ -7,12 +7,11 @@ import android.view.LayoutInflater
 import android.widget.LinearLayout
 import android.widget.TextView
 import androidx.core.content.ContextCompat
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
 import org.foxarmy.barcodescannerforemployees.R
 import org.foxarmy.barcodescannerforemployees.activities.ExpiryCalendarActivity
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
 import org.foxarmy.barcodescannerforemployees.database.ProductDAO
+import org.foxarmy.barcodescannerforemployees.getPreferences
 import java.text.SimpleDateFormat
 
 class ExpiryGroupView : LinearLayout {
@@ -24,13 +23,7 @@ class ExpiryGroupView : LinearLayout {
 
     constructor(activity: Activity, context: Context, representingDate: Long) : super(context) {
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            context,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(context)
 
         val dbHelper = DBStorageController(context, sharedPreferences.getString("currentGroup", "database")!!)
         productDAO = ProductDAO(dbHelper)

app/src/main/java/org/foxarmy/barcodescannerforemployees/views/GroupMemberView.kt

@@ -10,7 +10,7 @@ import org.foxarmy.barcodescannerforemployees.R
 class GroupMemberView : LinearLayout {
 
     private var username: String
-    private var userId: Int
+    var userId: Int
 
     constructor(activity: Activity, context: Context, username: String, userId: Int) : super(context) {
 

app/src/main/java/org/foxarmy/barcodescannerforemployees/views/ProductView.kt

@@ -13,6 +13,7 @@ import android.view.LayoutInflater
 import android.widget.ImageView
 import android.widget.LinearLayout
 import android.widget.TextView
+import android.widget.Toast
 import androidx.annotation.RequiresApi
 import androidx.constraintlayout.widget.ConstraintLayout
 import androidx.core.content.ContextCompat
@@ -21,29 +22,26 @@ import androidx.core.graphics.blue
 import androidx.core.graphics.green
 import androidx.core.graphics.red
 import androidx.core.math.MathUtils.clamp
-import androidx.security.crypto.EncryptedSharedPreferences
-import androidx.security.crypto.MasterKeys
-import org.foxarmy.barcodescannerforemployees.R
+import org.foxarmy.barcodescannerforemployees.*
 import org.foxarmy.barcodescannerforemployees.activities.FullscreenActivity
-import org.foxarmy.barcodescannerforemployees.calculateProductFreshness
+import org.foxarmy.barcodescannerforemployees.activities.MainActivity
 import org.foxarmy.barcodescannerforemployees.database.AbstractProductDAO
 import org.foxarmy.barcodescannerforemployees.database.CategoryDAO
 import org.foxarmy.barcodescannerforemployees.database.DBStorageController
 import org.foxarmy.barcodescannerforemployees.dataclasses.AbstractProduct
 import org.foxarmy.barcodescannerforemployees.dataclasses.Product
-import org.foxarmy.barcodescannerforemployees.getActivity
-import org.foxarmy.barcodescannerforemployees.getImageUri
 import java.io.File
 import java.text.DecimalFormat
 import java.text.SimpleDateFormat
 import java.util.*
 import kotlin.concurrent.thread
 
-class ProductView: LinearLayout {
+class ProductView : LinearLayout {
     var product: Product = Product()
     var isProductSelected = false
     private var activity: Activity
 
+    private lateinit var productLayout: ConstraintLayout
     private lateinit var productImageView: ImageView
     private lateinit var productNameTextView: TextView
     private lateinit var productNetWeightTextView: TextView
@@ -63,13 +61,7 @@ class ProductView: LinearLayout {
     constructor(context: Context, a: AttributeSet) : super(context, a) {
         activity = getActivity(context)!!
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            context,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(context)
 
         val dbHelper = DBStorageController(context, sharedPreferences.getString("currentGroup", "offline")!!)
         abstractProductDAO = AbstractProductDAO(dbHelper)
@@ -86,18 +78,13 @@ class ProductView: LinearLayout {
         val inflater: LayoutInflater = activity.layoutInflater
         inflater.inflate(R.layout.product_view, this)
 
-        sharedPreferences = EncryptedSharedPreferences.create(
-            "sensitive",
-            MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
-            context,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        sharedPreferences = getPreferences(context)
 
         val dbHelper = DBStorageController(context, sharedPreferences.getString("currentGroup", "offline")!!)
         abstractProductDAO = AbstractProductDAO(dbHelper)
         categoryDAO = CategoryDAO(dbHelper)
 
+        productLayout = findViewById(R.id.productLayout)
         productImageView = findViewById(R.id.productPicture)
         productNameTextView = findViewById(R.id.productNameView)
         productNetWeightTextView = findViewById(R.id.productNetWeightView)
@@ -106,68 +93,152 @@ class ProductView: LinearLayout {
         productLifeSpan = findViewById(R.id.dateSpan)
         productFreshnessTextView = findViewById(R.id.freshnessPercentTextView)
 
-        findViewById<ConstraintLayout>(R.id.productLayout).setOnLongClickListener {
-            isProductSelected = !isProductSelected
-            updateStroke()
-            true
-        }
-
-        productImageView.setOnClickListener {
-            val fullscreenIntent = Intent(activity, FullscreenActivity::class.java)
-            val extras = Bundle()
-            val abstractProduct = abstractProductDAO.findAbstractProductById(product.abstractProductId)
-            extras.putString("imagehash", abstractProduct!!.imageHash)
-            fullscreenIntent.putExtras(extras)
-            startActivity(context, fullscreenIntent, extras)
-        }
+        setUpClicks()
 
         update()
     }
 
     @RequiresApi(Build.VERSION_CODES.O)
-    fun update () {
-        val linkedAbstractProduct: AbstractProduct = abstractProductDAO.findAbstractProductById(product.abstractProductId) ?: return
+    private fun setUpClicks() {
+        productLayout.setOnLongClickListener { onAnyLongClick() }
+        productImageView.setOnLongClickListener { onImageLongClick() }
+        productNameTextView.setOnLongClickListener { onNameLongClick() }
+        productNetWeightTextView.setOnLongClickListener { onAnyLongClick() }
+        productAmountTextView.setOnLongClickListener { onAnyLongClick() }
+        productCategoryView.setOnLongClickListener { onAnyLongClick() }
+        productLifeSpan.setOnLongClickListener { onAnyLongClick() }
+        productFreshnessTextView.setOnLongClickListener { onAnyLongClick() }
+
+        productLayout.setOnClickListener { onAnyClick() }
+        productImageView.setOnClickListener { onImageLongClick() }
+        productNameTextView.setOnClickListener { onNameLongClick() }
+        productNetWeightTextView.setOnClickListener { onAnyClick() }
+        productAmountTextView.setOnClickListener { onAnyClick() }
+        productCategoryView.setOnClickListener { onAnyClick() }
+        productLifeSpan.setOnClickListener { onAnyClick() }
+        productFreshnessTextView.setOnClickListener { onAnyClick() }
+    }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    private fun onAnyClick(): Boolean {
+        if (activity !is MainActivity) return false
+        val mainActivity = activity as MainActivity
+
+        if (mainActivity.selectionMode) {
+            isProductSelected = !isProductSelected
+
+            if (isProductSelected) mainActivity.addSelection()
+            else mainActivity.removeSelection()
+
+            updateStroke()
+
+            return true
+        } else {
+            return false
+        }
+    }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    private fun onAnyLongClick(): Boolean {
+        if (activity !is MainActivity) return false
+        val mainActivity = activity as MainActivity
+
+        isProductSelected = !isProductSelected
+        updateStroke()
+
+        if (mainActivity.selectionMode) {
+            if (isProductSelected) mainActivity.addSelection()
+            else mainActivity.removeSelection()
+        } else {
+            mainActivity.addSelection()
+        }
+        return true
+
+    }
+
+    private fun onNameLongClick(): Boolean {
+        if (activity !is MainActivity) {
+            Toast.makeText(activity, productNameTextView.text, Toast.LENGTH_SHORT).show()
+            return true
+        }
+        val mainActivity = activity as MainActivity
+
+        if (mainActivity.selectionMode) return onAnyLongClick()
+        else Toast.makeText(activity, productNameTextView.text, Toast.LENGTH_SHORT).show()
+        return true
+    }
+
+    private fun onImageLongClick(): Boolean {
+        val abstractProduct = abstractProductDAO.findAbstractProductById(product.abstractProductId)
+
+        if (activity !is MainActivity) {
+            val fullscreenIntent = Intent(activity, FullscreenActivity::class.java)
+            val extras = Bundle()
+            extras.putString("imagehash", abstractProduct!!.imageHash)
+            fullscreenIntent.putExtras(extras)
+            startActivity(context, fullscreenIntent, extras)
+            return true
+        }
+        val mainActivity = activity as MainActivity
+
+        if (mainActivity.selectionMode) {
+            return onAnyLongClick()
+        } else {
+            val fullscreenIntent = Intent(activity, FullscreenActivity::class.java)
+            val extras = Bundle()
+            extras.putString("imagehash", abstractProduct!!.imageHash)
+            fullscreenIntent.putExtras(extras)
+            startActivity(context, fullscreenIntent, extras)
+        }
+        return true
+    }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    fun update() {
+        val linkedAbstractProduct: AbstractProduct =
+            abstractProductDAO.findAbstractProductById(product.abstractProductId) ?: return
 
         val thumbnailsDir = File(activity.cacheDir, "thumbnails")
         thumbnailsDir.mkdirs()
         val pictureFile = File(thumbnailsDir, "${linkedAbstractProduct.imageHash}.webp")
         val imageUri = getImageUri(activity, pictureFile)
         productImageView.setImageURI(imageUri)
-//        productImageView.rotation = 90f
 
         productNameTextView.text = linkedAbstractProduct.name
         productNetWeightTextView.text = linkedAbstractProduct.netWeight.toString()
         productAmountTextView.text = product.amount.toString()
         productCategoryView.text = categoryDAO.getCategoryNameById(linkedAbstractProduct.category)
-        productLifeSpan.text = "${SimpleDateFormat("dd.MM.yyyy").format(Date(product.dateOfProduction*1000))}-${SimpleDateFormat("dd.MM.yyyy").format(Date(product.dateOfExpiry*1000))}"
+        productLifeSpan.text = "${SimpleDateFormat("dd.MM.yyyy").format(Date(product.dateOfProduction * 1000))}-${
+            SimpleDateFormat("dd.MM.yyyy").format(Date(product.dateOfExpiry * 1000))
+        }"
         productFreshnessTextView.text =
-        if (product.freshness == Double.NEGATIVE_INFINITY || product.freshness == Double.POSITIVE_INFINITY || product.freshness < 0) {
-            context.getString(R.string.expired)
-        } else {
-            "${DecimalFormat("#.#").format(product.freshness*100)}%"
-        }
+            if (product.freshness == Double.NEGATIVE_INFINITY || product.freshness == Double.POSITIVE_INFINITY || product.freshness < 0) {
+                context.getString(R.string.expired)
+            } else {
+                "${DecimalFormat("#.#").format(product.freshness * 100)}%"
+            }
 
         updateStroke()
     }
 
     @RequiresApi(Build.VERSION_CODES.O)
     fun updateStroke() {
-         if (isProductSelected) {
-             this.background = ContextCompat.getDrawable(context, R.drawable.outline_selected)
-        } else {
-             if (product.id != 0) {
-                 thread {
-                     this.outline = GradientDrawable()
-                     backgroundColor = evaluateColor()
-                     strokeColor = darkenColor(backgroundColor, 0.25) // (backgroundColor and 0xfefefe ) shr 1
-                     this.outline.setColor(backgroundColor)
-                     this.outline.setStroke(4, strokeColor)
-                     this.outline.alpha = 84
-                     this.background = outline
-                 }
-             } else {
-                 this.background = ContextCompat.getDrawable(context, R.drawable.outline)
-             }
+        activity.runOnUiThread {
+            if (isProductSelected) {
+                this.background = ContextCompat.getDrawable(context, R.drawable.outline_selected)
+            } else {
+                if (product.id != 0) {
+                        this.outline = GradientDrawable()
+                        backgroundColor = evaluateColor()
+                        strokeColor = darkenColor(backgroundColor, 0.25) // (backgroundColor and 0xfefefe ) shr 1
+                        this.outline.setColor(backgroundColor)
+                        this.outline.setStroke(4, strokeColor)
+                        this.outline.alpha = 84
+                        this.background = outline
+                } else {
+                    this.background = ContextCompat.getDrawable(context, R.drawable.outline)
+                }
+            }
         }
     }
 
@@ -178,13 +249,15 @@ class ProductView: LinearLayout {
     }
 
     fun calculateFreshnessGradient(percentage: Double): Int {
-        val startColor = ContextCompat.getColor(context, if (percentage > 0.5) R.color.full_freshness else R.color.half_freshness)
-        val endColor = ContextCompat.getColor(context, if (percentage > 0.5) R.color.half_freshness else R.color.expired_freshness)
+        val startColor =
+            ContextCompat.getColor(context, if (percentage > 0.5) R.color.full_freshness else R.color.half_freshness)
+        val endColor =
+            ContextCompat.getColor(context, if (percentage > 0.5) R.color.half_freshness else R.color.expired_freshness)
 
         val gradientPosition = 1 - if (percentage > 0.5) (percentage - 0.5) * 2 else percentage * 2
 
-        val red = clamp((startColor.red + gradientPosition * (endColor.red - startColor.red )).toInt(), 0, 255)
-        val green = clamp((startColor.green  + gradientPosition * (endColor.green - startColor.green)).toInt(), 0, 255)
+        val red = clamp((startColor.red + gradientPosition * (endColor.red - startColor.red)).toInt(), 0, 255)
+        val green = clamp((startColor.green + gradientPosition * (endColor.green - startColor.green)).toInt(), 0, 255)
         val blue = clamp((startColor.blue + gradientPosition * (endColor.blue - startColor.blue)).toInt(), 0, 255)
 
         var redHex = Integer.toHexString(red)
@@ -194,7 +267,7 @@ class ProductView: LinearLayout {
         if (greenHex.length == 1) greenHex = "0$greenHex"
 
         var blueHex = Integer.toHexString(blue)
-        if (blueHex.length == 1 ) blueHex = "0$blueHex"
+        if (blueHex.length == 1) blueHex = "0$blueHex"
 
 
         val colorString = "#$redHex$greenHex$blueHex"
@@ -202,7 +275,7 @@ class ProductView: LinearLayout {
     }
 
     @RequiresApi(Build.VERSION_CODES.O)
-    fun darkenColor(color: Int, darkPercent: Double) : Int {
+    fun darkenColor(color: Int, darkPercent: Double): Int {
         val c = Color.valueOf(color)
 
         val red = c.red() * (1 - darkPercent)

app/src/main/res/layout/abstract_product_view.xml

@@ -8,7 +8,7 @@
     <androidx.constraintlayout.widget.ConstraintLayout
             android:layout_width="match_parent"
             android:layout_height="match_parent" android:id="@+id/productLayout" android:outlineProvider="bounds"
-            android:background="#00FFFEFE" android:clickable="true">
+            android:background="#00FFFEFE" android:clickable="true" android:translationZ="0sp">
         <ImageView
                 android:layout_width="match_parent"
                 android:layout_height="200dp" app:srcCompat="@android:drawable/ic_menu_gallery"

app/src/main/res/layout/activity_find_barcodeless_abstract_product.xml

@@ -1,10 +1,15 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.core.widget.NestedScrollView
+<androidx.constraintlayout.widget.ConstraintLayout
         xmlns:android="http://schemas.android.com/apk/res/android"
-        xmlns:tools="http://schemas.android.com/tools"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        tools:context=".fragments.ShelfFragment"
-        android:id="@+id/content">
+        xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent" android:layout_height="match_parent">
 
-</androidx.core.widget.NestedScrollView>
+    <androidx.core.widget.NestedScrollView
+            android:layout_height="0dp"
+            tools:context=".fragments.ShelfFragment"
+            android:id="@+id/content" android:layout_width="0dp" app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintStart_toStartOf="parent" app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent">
+
+    </androidx.core.widget.NestedScrollView>
+</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/layout/activity_main.xml

@@ -39,12 +39,13 @@
             <androidx.viewpager.widget.ViewPager
                     android:id="@+id/tab_viewpager"
                     android:layout_width="0dp"
-                    android:layout_height="777dp"
+                    android:layout_height="0dp"
                     app:layout_behavior="@string/appbar_scrolling_view_behavior" android:layout_gravity="bottom"
                     android:layout_marginTop="2dp"
                     app:layout_constraintTop_toBottomOf="@+id/appBarLayout"
                     app:layout_constraintStart_toStartOf="parent" android:layout_marginStart="6dp"
-                    app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="6dp"/>
+                    app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="6dp"
+                    app:layout_constraintBottom_toBottomOf="parent"/>
             <com.google.android.material.floatingactionbutton.FloatingActionButton
                     android:id="@+id/new_element_fab"
                     android:layout_width="wrap_content"

app/src/main/res/layout/content_storage.xml

@@ -1,20 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout
-        xmlns:android="http://schemas.android.com/apk/res/android"
-        xmlns:app="http://schemas.android.com/apk/res-auto"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        app:layout_behavior="@string/appbar_scrolling_view_behavior" android:id="@+id/storageLayout">
-
-    <fragment
-            android:id="@+id/nav_host_fragment_content_storage"
-            android:name="androidx.navigation.fragment.NavHostFragment"
-            android:layout_width="0dp"
-            android:layout_height="0dp"
-            app:layout_constraintStart_toStartOf="parent"
-            app:layout_constraintEnd_toEndOf="parent"
-            app:layout_constraintTop_toTopOf="parent"
-            app:layout_constraintBottom_toBottomOf="parent"
-            app:defaultNavHost="true"
-            app:navGraph="@navigation/nav_graph_main"/>
-</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/layout/fragment_add_abstract_product.xml

@@ -62,7 +62,7 @@
                 android:ems="10"
                 android:id="@+id/barcodeTextEdit" app:layout_constraintTop_toBottomOf="@+id/imageView"
                 app:layout_constraintStart_toStartOf="parent"
-                android:layout_marginTop="8dp" android:hint="Barcode" android:textColorHint="#737373"
+                android:layout_marginTop="8dp" android:hint="@string/barcode" android:textColorHint="#737373"
                 android:layout_marginStart="5dp"/>
         <CheckBox
                 android:text="@string/no_barcode"

app/src/main/res/layout/fragment_shelf.xml

@@ -2,7 +2,7 @@
 <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent"
              android:layout_height="match_parent"
-             android:background="#141218">
+>
 
     <androidx.constraintlayout.widget.ConstraintLayout
             android:layout_width="match_parent"
@@ -26,7 +26,8 @@
                 android:layout_width="match_parent"
                 android:layout_height="match_parent" app:layout_constraintTop_toBottomOf="@+id/spinner"
                 android:layout_marginTop="32dp" app:layout_constraintStart_toStartOf="parent"
-                app:layout_constraintEnd_toEndOf="parent" android:id="@+id/scrollView">
+                app:layout_constraintEnd_toEndOf="parent" android:id="@+id/scrollView"
+                app:layout_constraintBottom_toBottomOf="parent">
             <androidx.gridlayout.widget.GridLayout
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content" android:id="@+id/contentGridLayout" app:columnCount="2"

app/src/main/res/layout/fragment_storage.xml

@@ -1,13 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
-             xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools"
-             android:layout_width="match_parent"
-             android:layout_height="match_parent"
-             android:id="@+id/fragment_storage"
-             tools:context=".fragments.StorageFragment">
-    <androidx.constraintlayout.widget.ConstraintLayout
-            android:layout_width="match_parent"
-            android:layout_height="match_parent">
+
+<androidx.constraintlayout.widget.ConstraintLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto">
 
         <TextView
                 android:text="@string/sort_by"
@@ -16,7 +12,7 @@
                 app:layout_constraintStart_toStartOf="parent"
                 app:layout_constraintTop_toTopOf="parent"
                 android:textAlignment="center"
-                app:layout_constraintBottom_toBottomOf="@+id/scrollView2"/>
+                app:layout_constraintBottom_toTopOf="@+id/scrollView2"/>
         <Spinner
                 android:layout_width="0dp"
                 android:layout_height="32dp" android:id="@+id/spinner"
@@ -34,15 +30,16 @@
                 android:layout_marginEnd="10dp" app:layout_constraintTop_toTopOf="parent"/>
         <ScrollView
                 android:layout_width="match_parent"
-                android:layout_height="wrap_content"
+                android:layout_height="0dp"
                 android:id="@+id/scrollView2"
-                app:layout_constraintTop_toBottomOf="@+id/dropFiltersButton">
+                app:layout_constraintTop_toBottomOf="@+id/dropFiltersButton"
+                android:layout_marginTop="4dp" app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintEnd_toEndOf="parent">
             <androidx.gridlayout.widget.GridLayout
                     android:layout_width="match_parent"
-                    android:layout_height="wrap_content" android:id="@+id/contentGridLayout" app:columnCount="2"
+                    android:layout_height="match_parent" android:id="@+id/contentGridLayout" app:columnCount="2"
                     app:rowCount="100" android:nestedScrollingEnabled="true">
 
             </androidx.gridlayout.widget.GridLayout>
         </ScrollView>
     </androidx.constraintlayout.widget.ConstraintLayout>
-</FrameLayout>

app/src/main/res/menu/drawer_menu.xml

@@ -12,4 +12,5 @@
     <item
             android:id="@+id/nav_settings"
             android:title="@string/settings"/>
+    <item android:title="@string/logout" android:id="@+id/nav_logout"/>
 </menu>

app/src/main/res/menu/user_pop_menu.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item android:title="@string/kick" android:id="@+id/kick"/>
+    <item android:title="@string/transfer_ownership" android:id="@+id/transfer_ownership"/>
+</menu>

app/src/main/res/values-ru/strings.xml

@@ -114,6 +114,18 @@
     <string name="image_compress_factor">Степень сжатия изображения</string>
     <string name="current_group">Текущая группа</string>
     <string name="cancel">Отмена</string>
+    <string name="no_internet_connection">Не могу установить соединение с сервером. Возможно, вы отключены от сети?</string>
+    <string name="ok">Ок</string>
+    <string name="logout">Выйти</string>
+    <string name="online_only_feature">Эта возможность доступна только с онлайн аккаунтом</string>
+    <string name="username_changed">Имя пользователя изменено. Пожалуйста, перезайдите</string>
+    <string name="password_changed">Пароль изменён. Пожалуйста, перезайдите</string>
+    <string name="new_group_name">Введите новое имя группы</string>
+    <string name="kick">Выгнать</string>
+    <string name="transfer_ownership">Передать владение группой</string>
+    <string name="transfer_ownership_confirmation">Вы увереных, что хотите передать владение группой этому пользователю?</string>
+    <string name="loading_please_wait">Загрузка, пожалуйста ждите</string>
+    <string name="loading">Загрузка</string>
     <string-array name="languages">
         <item>en-US</item>
         <item>ru-RU</item>

app/src/main/res/values/strings.xml

@@ -112,6 +112,18 @@
     <string name="image_compress_factor">Image compression factor</string>
     <string name="current_group">Current group</string>
     <string name="cancel">Cancel</string>
+    <string name="no_internet_connection">Cannot reach the server. Maybe, you lost internet connection?</string>
+    <string name="ok">OK</string>
+    <string name="logout">Log out</string>
+    <string name="online_only_feature">This feature is online only</string>
+    <string name="username_changed">Your username has been changed. Please, relogin</string>
+    <string name="password_changed">You password was changed. Please, relogin</string>
+    <string name="new_group_name">Enter new group name</string>
+    <string name="kick">Kick</string>
+    <string name="transfer_ownership">Transfer ownership</string>
+    <string name="transfer_ownership_confirmation">Are you sure you want to transfer ownership on current group to that user?</string>
+    <string name="loading_please_wait">Loading, please wait</string>
+    <string name="loading">Loading</string>
     <string-array name="languages">
         <item>en-US</item>
         <item>ru-RU</item>