Implement optional separate app notification channels

app/src/main/kotlin/com/github/gotify/NotificationSupport.kt

@@ -1,56 +1,92 @@
 package com.github.gotify
 
 import android.app.NotificationChannel
+import android.app.NotificationChannelGroup
 import android.app.NotificationManager
+import android.content.Context
 import android.graphics.Color
 import android.os.Build
 import androidx.annotation.RequiresApi
+import androidx.preference.PreferenceManager
+import com.github.gotify.client.model.Application
 import com.github.gotify.log.Log
 
 internal object NotificationSupport {
     @RequiresApi(Build.VERSION_CODES.O)
-    fun createChannels(notificationManager: NotificationManager) {
+    fun createForegroundChannel(context: Context, notificationManager: NotificationManager) {
-        try {
+        // Low importance so that persistent notification can be sorted towards bottom of
-            // Low importance so that persistent notification can be sorted towards bottom of
+        // notification shade. Also prevents vibrations caused by persistent notification
-            // notification shade. Also prevents vibrations caused by persistent notification
+        val foreground = NotificationChannel(
-            val foreground = NotificationChannel(
+            Channel.FOREGROUND,
-                Channel.FOREGROUND,
+            context.getString(R.string.notification_channel_title_foreground),
-                "Gotify foreground notification",
+            NotificationManager.IMPORTANCE_LOW
-                NotificationManager.IMPORTANCE_LOW
+        ).apply {
-            )
+            setShowBadge(false)
-            foreground.setShowBadge(false)
+        }
+        notificationManager.createNotificationChannel(foreground)
+    }
 
+    @RequiresApi(Build.VERSION_CODES.O)
+    fun createChannels(
+        context: Context,
+        notificationManager: NotificationManager,
+        applications: List<Application>
+    ) {
+        if (areAppChannelsRequested(context)) {
+            notificationManager.notificationChannels.forEach { channel ->
+                if (channel.id != Channel.FOREGROUND) {
+                    notificationManager.deleteNotificationChannel(channel.id)
+                }
+            }
+            applications.forEach { app ->
+                createAppChannels(context, notificationManager, app.id.toString(), app.name)
+            }
+        } else {
+            notificationManager.notificationChannelGroups.forEach { group ->
+                notificationManager.deleteNotificationChannelGroup(group.id)
+            }
+            createGeneralChannels(context, notificationManager)
+        }
+    }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    private fun createGeneralChannels(
+        context: Context,
+        notificationManager: NotificationManager
+    ) {
+        try {
             val messagesImportanceMin = NotificationChannel(
                 Channel.MESSAGES_IMPORTANCE_MIN,
-                "Min priority messages (<1)",
+                context.getString(R.string.notification_channel_title_min),
                 NotificationManager.IMPORTANCE_MIN
             )
 
             val messagesImportanceLow = NotificationChannel(
                 Channel.MESSAGES_IMPORTANCE_LOW,
-                "Low priority messages (1-3)",
+                context.getString(R.string.notification_channel_title_low),
                 NotificationManager.IMPORTANCE_LOW
             )
 
             val messagesImportanceDefault = NotificationChannel(
                 Channel.MESSAGES_IMPORTANCE_DEFAULT,
-                "Normal priority messages (4-7)",
+                context.getString(R.string.notification_channel_title_normal),
                 NotificationManager.IMPORTANCE_DEFAULT
-            )
+            ).apply {
-            messagesImportanceDefault.enableLights(true)
+                enableLights(true)
-            messagesImportanceDefault.lightColor = Color.CYAN
+                lightColor = Color.CYAN
-            messagesImportanceDefault.enableVibration(true)
+                enableVibration(true)
+            }
 
             val messagesImportanceHigh = NotificationChannel(
                 Channel.MESSAGES_IMPORTANCE_HIGH,
-                "High priority messages (>7)",
+                context.getString(R.string.notification_channel_title_high),
                 NotificationManager.IMPORTANCE_HIGH
-            )
+            ).apply {
-            messagesImportanceHigh.enableLights(true)
+                enableLights(true)
-            messagesImportanceHigh.lightColor = Color.CYAN
+                lightColor = Color.CYAN
-            messagesImportanceHigh.enableVibration(true)
+                enableVibration(true)
+            }
 
-            notificationManager.createNotificationChannel(foreground)
             notificationManager.createNotificationChannel(messagesImportanceMin)
             notificationManager.createNotificationChannel(messagesImportanceLow)
             notificationManager.createNotificationChannel(messagesImportanceDefault)
@@ -60,6 +96,88 @@ internal object NotificationSupport {
         }
     }
 
+    @RequiresApi(api = Build.VERSION_CODES.O)
+    fun createChannelIfNonexistent(
+        context: Context,
+        notificationManager: NotificationManager,
+        groupId: String,
+        groupName: String,
+        channelId: String
+    ) {
+        if (!doesNotificationChannelExist(context, channelId)) {
+            createAppChannels(context, notificationManager, groupId, groupName)
+        }
+    }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    private fun createAppChannels(
+        context: Context,
+        notificationManager: NotificationManager,
+        groupId: String,
+        groupName: String
+    ) {
+        try {
+            notificationManager.createNotificationChannelGroup(
+                NotificationChannelGroup(
+                    groupId,
+                    groupName
+                )
+            )
+
+            val messagesImportanceMin = NotificationChannel(
+                getChannelID(Channel.MESSAGES_IMPORTANCE_MIN, groupId),
+                context.getString(R.string.notification_channel_title_min),
+                NotificationManager.IMPORTANCE_MIN
+            ).apply {
+                group = groupId
+            }
+
+            val messagesImportanceLow = NotificationChannel(
+                getChannelID(Channel.MESSAGES_IMPORTANCE_LOW, groupId),
+                context.getString(R.string.notification_channel_title_low),
+                NotificationManager.IMPORTANCE_LOW
+            ).apply {
+                group = groupId
+            }
+
+            val messagesImportanceDefault = NotificationChannel(
+                getChannelID(Channel.MESSAGES_IMPORTANCE_DEFAULT, groupId),
+                context.getString(R.string.notification_channel_title_normal),
+                NotificationManager.IMPORTANCE_DEFAULT
+            ).apply {
+                enableLights(true)
+                lightColor = Color.CYAN
+                enableVibration(true)
+                group = groupId
+            }
+
+            val messagesImportanceHigh = NotificationChannel(
+                getChannelID(Channel.MESSAGES_IMPORTANCE_HIGH, groupId),
+                context.getString(R.string.notification_channel_title_high),
+                NotificationManager.IMPORTANCE_HIGH
+            ).apply {
+                enableLights(true)
+                lightColor = Color.CYAN
+                enableVibration(true)
+                group = groupId
+            }
+
+            notificationManager.createNotificationChannel(messagesImportanceMin)
+            notificationManager.createNotificationChannel(messagesImportanceLow)
+            notificationManager.createNotificationChannel(messagesImportanceDefault)
+            notificationManager.createNotificationChannel(messagesImportanceHigh)
+        } catch (e: Exception) {
+            Log.e("Could not create channel", e)
+        }
+    }
+
+    @RequiresApi(api = Build.VERSION_CODES.O)
+    private fun doesNotificationChannelExist(context: Context, channelId: String): Boolean {
+        val manager = context.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
+        val channel = manager.getNotificationChannel(channelId)
+        return channel != null
+    }
+
     /**
      * Map {@link com.github.gotify.client.model.Message#getPriority() Gotify message priorities to
      * Android channels.
@@ -87,6 +205,21 @@ internal object NotificationSupport {
         }
     }
 
+    private fun getChannelID(importance: String, groupId: String): String {
+        return "$importance::$groupId"
+    }
+
+    fun getChannelID(priority: Long, groupId: String): String {
+        return getChannelID(convertPriorityToChannel(priority), groupId)
+    }
+
+    fun areAppChannelsRequested(context: Context): Boolean {
+        return PreferenceManager.getDefaultSharedPreferences(context).getBoolean(
+            context.getString(R.string.setting_key_notification_channels),
+            context.resources.getBoolean(R.bool.notification_channels)
+        )
+    }
+
     object Group {
         const val MESSAGES = "GOTIFY_GROUP_MESSAGES"
     }

app/src/main/kotlin/com/github/gotify/init/InitializationActivity.kt

@@ -2,6 +2,7 @@ package com.github.gotify.init
 
 import android.Manifest
 import android.app.NotificationManager
+import android.content.Context
 import android.content.Intent
 import android.os.Build
 import android.os.Bundle
@@ -41,8 +42,9 @@ internal class InitializationActivity : AppCompatActivity() {
         ThemeHelper.setTheme(this, theme)
 
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
-            NotificationSupport.createChannels(
+            NotificationSupport.createForegroundChannel(
-                this.getSystemService(NOTIFICATION_SERVICE) as NotificationManager
+                this,
+                (this.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager)
             )
         }
         UncaughtExceptionHandler.registerCurrentThread()

app/src/main/kotlin/com/github/gotify/messages/MessagesActivity.kt

@@ -9,6 +9,7 @@ import android.graphics.Canvas
 import android.graphics.drawable.ColorDrawable
 import android.graphics.drawable.Drawable
 import android.net.Uri
+import android.os.Build
 import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
@@ -28,6 +29,7 @@ import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import com.github.gotify.BuildConfig
 import com.github.gotify.MissedMessageUtil
+import com.github.gotify.NotificationSupport
 import com.github.gotify.R
 import com.github.gotify.Utils
 import com.github.gotify.Utils.launchCoroutine
@@ -204,6 +206,14 @@ internal class MessagesActivity :
                 .into(t)
         }
         selectAppInMenu(selectedItem)
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            NotificationSupport.createChannels(
+                this,
+                (this.getSystemService(NOTIFICATION_SERVICE) as NotificationManager),
+                applications
+            )
+        }
     }
 
     private fun initDrawer() {

app/src/main/kotlin/com/github/gotify/service/WebSocketService.kt

@@ -5,6 +5,7 @@ import android.app.Notification
 import android.app.NotificationManager
 import android.app.PendingIntent
 import android.app.Service
+import android.content.Context
 import android.content.Intent
 import android.content.IntentFilter
 import android.graphics.Color
@@ -312,13 +313,26 @@ internal class WebSocketService : Service() {
             PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
         )
 
-        val b = NotificationCompat.Builder(
+        val channelId: String
-            this,
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O &&
-            NotificationSupport.convertPriorityToChannel(priority)
+            NotificationSupport.areAppChannelsRequested(this)
-        )
+        ) {
+            channelId = NotificationSupport.getChannelID(priority, appId.toString())
+            NotificationSupport.createChannelIfNonexistent(
+                this,
+                (this.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager),
+                appId.toString(),
+                appId.toString(),
+                channelId
+            )
+        } else {
+            channelId = NotificationSupport.convertPriorityToChannel(priority)
+        }
+
+        val b = NotificationCompat.Builder(this, channelId)
 
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
-            showNotificationGroup(priority)
+            showNotificationGroup(channelId)
         }
 
         b.setAutoCancel(true)
@@ -365,7 +379,7 @@ internal class WebSocketService : Service() {
     }
 
     @RequiresApi(Build.VERSION_CODES.N)
-    fun showNotificationGroup(priority: Long) {
+    fun showNotificationGroup(channelId: String) {
         val intent = Intent(this, MessagesActivity::class.java)
         val contentIntent = PendingIntent.getActivity(
             this,
@@ -376,7 +390,7 @@ internal class WebSocketService : Service() {
 
         val builder = NotificationCompat.Builder(
             this,
-            NotificationSupport.convertPriorityToChannel(priority)
+            channelId
         )
 
         builder.setAutoCancel(true)

app/src/main/kotlin/com/github/gotify/settings/SettingsActivity.kt

@@ -5,6 +5,7 @@ import android.content.DialogInterface
 import android.content.Intent
 import android.content.SharedPreferences
 import android.content.SharedPreferences.OnSharedPreferenceChangeListener
+import android.os.Build
 import android.os.Bundle
 import android.view.MenuItem
 import android.view.View
@@ -14,6 +15,7 @@ import androidx.preference.ListPreferenceDialogFragmentCompat
 import androidx.preference.Preference
 import androidx.preference.PreferenceFragmentCompat
 import androidx.preference.PreferenceManager
+import androidx.preference.SwitchPreferenceCompat
 import com.github.gotify.R
 import com.github.gotify.databinding.SettingsActivityBinding
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
@@ -48,17 +50,36 @@ internal class SettingsActivity : AppCompatActivity(), OnSharedPreferenceChangeL
     }
 
     override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences, key: String) {
-        if (getString(R.string.setting_key_theme) == key) {
+        when (key) {
-            ThemeHelper.setTheme(
+            getString(R.string.setting_key_theme) -> {
-                this,
+                ThemeHelper.setTheme(
-                sharedPreferences.getString(key, getString(R.string.theme_default))!!
+                    this,
-            )
+                    sharedPreferences.getString(key, getString(R.string.theme_default))!!
+                )
+            }
+            getString(R.string.setting_key_notification_channels) -> {
+                if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) return
+
+                val dialogBuilder = MaterialAlertDialogBuilder(this)
+                    .setTitle(R.string.setting_notification_channels_dialog_title)
+                    .setMessage(R.string.setting_notification_channels_dialog_message)
+                    .setPositiveButton(android.R.string.ok, null)
+
+                if (!isFinishing) {
+                    dialogBuilder.show()
+                }
+            }
         }
     }
 
     class SettingsFragment : PreferenceFragmentCompat() {
         override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
             setPreferencesFromResource(R.xml.root_preferences, rootKey)
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+                findPreference<SwitchPreferenceCompat>(
+                    getString(R.string.setting_key_notification_channels)
+                )?.isEnabled = true
+            }
         }
 
         override fun onViewCreated(view: View, savedInstanceState: Bundle?) {

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

@@ -34,4 +34,5 @@
     </string-array>
     <string name="time_format_value_absolute">time_format_absolute</string>
     <string name="time_format_value_relative">time_format_relative</string>
+    <bool name="notification_channels">false</bool>
 </resources>

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

@@ -80,6 +80,11 @@
     <string name="setting_message_layout_dialog_button2">Later</string>
     <string name="setting_time_format">Time format</string>
     <string name="setting_key_time_format">time_format</string>
+    <string name="setting_notifications">Notifications</string>
+    <string name="setting_notification_channels">Separate app notification channels</string>
+    <string name="setting_key_notification_channels">notification_channels</string>
+    <string name="setting_notification_channels_dialog_title">Manual refresh required</string>
+    <string name="setting_notification_channels_dialog_message">For the change to take effect you must manually refresh the apps using the refresh button in the main menu.</string>
     <string name="push_message">Push message</string>
     <string name="appListDescription">App:</string>
     <string name="priorityDescription">Priority:</string>
@@ -97,4 +102,10 @@
         <item quantity="one">in %d minute</item>
         <item quantity="other">in %d minutes</item>
     </plurals>
+
+    <string name="notification_channel_title_foreground">Gotify foreground notification</string>
+    <string name="notification_channel_title_min">Min priority messages (&lt;1)</string>
+    <string name="notification_channel_title_low">Low priority messages (1–3)</string>
+    <string name="notification_channel_title_normal">Normal priority messages (4–7)</string>
+    <string name="notification_channel_title_high">High priority messages (>7)</string>
 </resources>

app/src/main/res/xml/root_preferences.xml

@@ -24,4 +24,13 @@
             android:title="@string/setting_time_format" />
     </PreferenceCategory>
 
+    <PreferenceCategory app:title="@string/setting_notifications" >
+        <SwitchPreferenceCompat
+            android:enabled="false"
+            android:defaultValue="@bool/notification_channels"
+            android:key="@string/setting_key_notification_channels"
+            android:title="@string/setting_notification_channels"
+            app:singleLineTitle="false" />
+    </PreferenceCategory>
+
 </PreferenceScreen>