fix(android/ios): keep calls active in background

src-tauri/gen/android/app/src/main/AndroidManifest.xml

@@ -11,6 +11,12 @@
     <uses-permission android:name="android.permission.CAMERA" />
     <uses-permission android:name="android.permission.RECORD_AUDIO" />
     <uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
+
+    <!-- Foreground service for ongoing calls (microphone|mediaPlayback on API 34+) -->
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MICROPHONE" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MEDIA_PLAYBACK" />
+
     <uses-feature android:name="android.hardware.camera" android:required="false" />
     <uses-feature android:name="android.hardware.microphone" android:required="false" />
 
@@ -111,6 +117,11 @@
             <!-- DEEP LINK PLUGIN. AUTO-GENERATED. DO NOT REMOVE. -->
         </activity>
 
+        <service
+            android:name="moe.sable.client.CallForegroundService"
+            android:exported="false"
+            android:foregroundServiceType="microphone|mediaPlayback" />
+
         <provider
           android:name="androidx.core.content.FileProvider"
           android:authorities="${applicationId}.fileprovider"

src-tauri/gen/android/app/src/main/java/moe/sable/client/CallForegroundService.kt

@@ -0,0 +1,52 @@
+package moe.sable.client
+
+import android.app.Notification
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.Service
+import android.content.Intent
+import android.os.Build
+import android.os.IBinder
+import androidx.core.app.NotificationCompat
+
+class CallForegroundService : Service() {
+  override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+    createNotificationChannel()
+    startForeground(NOTIFICATION_ID, buildNotification())
+    return START_NOT_STICKY
+  }
+
+  override fun onBind(intent: Intent?): IBinder? = null
+
+  override fun onDestroy() {
+    stopForeground(true)
+    super.onDestroy()
+  }
+
+  private fun createNotificationChannel() {
+    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) return
+
+    val channel = NotificationChannel(
+      CHANNEL_ID,
+      "Calls",
+      NotificationManager.IMPORTANCE_LOW
+    )
+    getSystemService(NotificationManager::class.java).createNotificationChannel(channel)
+  }
+
+  private fun buildNotification(): Notification {
+    return NotificationCompat.Builder(this, CHANNEL_ID)
+      .setSmallIcon(R.mipmap.ic_notification)
+      .setContentTitle("Call in progress")
+      .setContentText("Sable is keeping your call active")
+      .setCategory(Notification.CATEGORY_CALL)
+      .setOngoing(true)
+      .setOnlyAlertOnce(true)
+      .build()
+  }
+
+  companion object {
+    private const val CHANNEL_ID = "call_foreground"
+    private const val NOTIFICATION_ID = 1395
+  }
+}

src-tauri/gen/android/app/src/main/java/moe/sable/client/MainActivity.kt

@@ -10,6 +10,7 @@ import android.provider.OpenableColumns
 import android.webkit.WebView
 import androidx.activity.OnBackPressedCallback
 import androidx.activity.enableEdgeToEdge
+import androidx.core.content.ContextCompat
 import androidx.core.content.IntentCompat
 import androidx.core.view.WindowCompat
 import java.io.File
@@ -208,5 +209,24 @@ class MainActivity : TauriActivity() {
         }
       }
     }
+
+    @JvmStatic
+    fun startCallForegroundServiceNative() {
+      val activity = instance ?: return
+      activity.runOnUiThread {
+        ContextCompat.startForegroundService(
+          activity,
+          Intent(activity, CallForegroundService::class.java)
+        )
+      }
+    }
+
+    @JvmStatic
+    fun stopCallForegroundServiceNative() {
+      val activity = instance ?: return
+      activity.runOnUiThread {
+        activity.stopService(Intent(activity, CallForegroundService::class.java))
+      }
+    }
   }
 }

src-tauri/ios-project.yml

@@ -102,6 +102,7 @@ targets:
           - UIInterfaceOrientationLandscapeRight
         CFBundleShortVersionString: {{apple.bundle-version-short}}
         CFBundleVersion: "{{apple.bundle-version}}"
+        UIBackgroundModes: [audio]
         # Mirrors plugins.deep-link in tauri.conf.json: the plugin only patches
         # these in when cargo reruns its build script, so a fresh `tauri ios
         # init` silently loses them unless they live here.

src-tauri/src/lib.rs

@@ -451,6 +451,10 @@ pub fn run() {
             mobile::set_status_bar_color,
             #[cfg(target_os = "android")]
             mobile::set_navigation_bar_color,
+            #[cfg(target_os = "android")]
+            mobile::start_call_foreground_service,
+            #[cfg(target_os = "android")]
+            mobile::stop_call_foreground_service,
             #[cfg(target_os = "ios")]
             ios::haptic_feedback,
             #[cfg(any(target_os = "android", target_os = "ios"))]

src-tauri/src/mobile.rs

@@ -34,6 +34,16 @@ pub fn set_navigation_bar_color(color: u32) -> Result<(), String> {
     call_bar_color("setNavigationBarColorNative", color)
 }
 
+#[tauri::command]
+pub fn start_call_foreground_service() -> Result<(), String> {
+    call_static_method("startCallForegroundServiceNative")
+}
+
+#[tauri::command]
+pub fn stop_call_foreground_service() -> Result<(), String> {
+    call_static_method("stopCallForegroundServiceNative")
+}
+
 /// `kind` is "notification" or "invite"; mapped to an int to avoid JNI string
 /// marshalling (mirrors set_*_bar_color).
 pub(crate) fn play_notification_sound(kind: String) -> Result<(), String> {
@@ -75,3 +85,16 @@ fn call_bar_color(method: &str, color: u32) -> Result<(), String> {
 
     Ok(())
 }
+
+fn call_static_method(method: &str) -> Result<(), String> {
+    let vm = JAVA_VM.get().ok_or("java vm not initialized")?;
+    let mut env = vm.attach_current_thread().map_err(|e| e.to_string())?;
+
+    let result = env.call_static_method("moe/sable/client/MainActivity", method, "()V", &[]);
+    if result.is_err() {
+        let _ = env.exception_clear();
+    }
+    result.map_err(|e| e.to_string())?;
+
+    Ok(())
+}

src/app/plugins/call/CallEmbed.ts

@@ -1,5 +1,6 @@
 import type { MatrixClient, MatrixEvent, Room } from '$types/matrix-sdk';
 import { ClientEvent, KnownMembership, MatrixEventEvent, RoomStateEvent } from '$types/matrix-sdk';
+import { invoke } from '@tauri-apps/api/core';
 import type { IRoomEvent, IWidget, WidgetDriver } from 'matrix-widget-api';
 import {
   ClientWidgetApi,
@@ -10,7 +11,7 @@ import {
 } from 'matrix-widget-api';
 import { CallWidgetDriver } from './CallWidgetDriver';
 import { trimTrailingSlash } from '../../utils/common';
-import { getWindowOrigin } from '../../utils/platform';
+import { getWindowOrigin, isAndroidTauri } from '../../utils/platform';
 import type { ElementCallThemeKind, ElementMediaStateDetail } from './types';
 import { color, config } from 'folds';
 import { ElementCallIntent, ElementWidgetActions } from './types';
@@ -355,6 +356,7 @@ export class CallEmbed {
    */
   public dispose(): void {
     debugLog.info('call', 'Disposing call widget', { roomId: this.roomId });
+    this.invokeForegroundService('stop_call_foreground_service');
     this.disposables.forEach((disposable) => {
       disposable();
     });
@@ -373,10 +375,18 @@ export class CallEmbed {
     this.call.transport.reply(evt.detail as IWidgetApiRequest, {});
     debugLog.info('call', 'Call joined', { roomId: this.roomId });
     this.joined = true;
+    this.invokeForegroundService('start_call_foreground_service');
     this.applyStyles();
     this.control.startObserving();
   }
 
+  private invokeForegroundService(
+    command: 'start_call_foreground_service' | 'stop_call_foreground_service'
+  ): void {
+    if (!isAndroidTauri()) return;
+    void invoke(command).catch(() => {});
+  }
+
   private applyStyles(): void {
     const doc = this.document;
     if (!doc) return;