Duplicate Firebase Push Notifications

[Mohamed-7018]

While developing my app, I incorporated firebase notifications using the tutorial guides provided by firebase. However, I am encountering an issue where other devices receive two notifications instead of one. Additionally, the device that sends the notification receives the same notification, even though it shouldn't. I came across similar queries that had to do with duplicate notifications. On another note, I am interested in learning how to manually send push notifications to devices within a certain location.

Here is my flutter doctor-v output

My dart code

@pragma('vm:entry-point')
Future<void> _firebaseMessagingBackgroundHandler(RemoteMessage message) async {
  await Firebase.initializeApp(options: DefaultFirebaseOptions.currentPlatform);
  await setupFlutterNotifications();
  showFlutterNotification(message);
  // If you're going to use other Firebase services in the background, such as Firestore,
  // make sure you call `initializeApp` before using other Firebase services.
  print('Handling a background message ${message.messageId}');
}

void getToken() async {
  await FirebaseMessaging.instance.getToken().then((token) {
    print('token -> $token');
  });
}

void requestPermission() async {
    FirebaseMessaging messaging = FirebaseMessaging.instance;

    NotificationSettings settings = await messaging.requestPermission(
      alert: true,
      announcement: false,
      badge: true,
      carPlay: false,
      criticalAlert: false,
      provisional: false,
      sound: true,
    );

    if (settings.authorizationStatus == AuthorizationStatus.authorized) {
      print('User granted permission');
    } else if (settings.authorizationStatus == AuthorizationStatus.provisional) {
      print('User granted provisional permission');
    } else {
      print('User declined or has not accepted permission');
    }
  }

/// Create a [AndroidNotificationChannel] for heads up notifications
late AndroidNotificationChannel channel;

bool isFlutterLocalNotificationsInitialized = false;
 
late FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin ;


Future<void> setupFlutterNotifications() async {
  if (isFlutterLocalNotificationsInitialized) {
    return;
  }
  channel = const AndroidNotificationChannel(
    'high_importance_channel', // id
    'High Importance Notifications', // title
    description:
        'This channel is used for important notifications.', // description
    importance: Importance.high,
  );

   flutterLocalNotificationsPlugin = FlutterLocalNotificationsPlugin();

  /// Create an Android Notification Channel.
  ///
  /// We use this channel in the `AndroidManifest.xml` file to override the
  /// default FCM channel to enable heads up notifications.
  await flutterLocalNotificationsPlugin
      .resolvePlatformSpecificImplementation<
          AndroidFlutterLocalNotificationsPlugin>()
      ?.createNotificationChannel(channel);

  /// Update the iOS foreground notification presentation options to allow
  /// heads up notifications.
  await FirebaseMessaging.instance.setForegroundNotificationPresentationOptions(
    alert: true,
    badge: true,
    sound: true,
  );
  isFlutterLocalNotificationsInitialized = true;
}

void showFlutterNotification(
  RemoteMessage message) {
  RemoteNotification? notification = message.notification;
  AndroidNotification? android = message.notification?.android;
  if (notification != null && android != null && !kIsWeb) {
    flutterLocalNotificationsPlugin.show(
      notification.hashCode,
      notification.title,
      notification.body,
      NotificationDetails(
        android: AndroidNotificationDetails(
          channel.id,
          channel.name,
          channelDescription: channel.description,
          //      one that already exists in example app.
          icon: 'ic_stat_ic_notification',
        ),
      ),
    );
  }
}

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );

  // Set the background messaging handler early on, as a named top-level function
  FirebaseMessaging.onBackgroundMessage(_firebaseMessagingBackgroundHandler);

  if (!kIsWeb) {
    await setupFlutterNotifications();
  }

  requestPermission();
  getToken();

  await FirebaseMessaging.instance.getInitialMessage();

  FirebaseMessaging.onMessage.listen(showFlutterNotification);
 
  // .... other code

  runApp(MyApp(
    init: init,
  ));
}

I made several attempts to identify the issue, but unfortunately, I was unable to determine its root cause. If there is a need for additional information, I will make necessary edits to include it.

[credotim]

Did you find solution?

[Mohamed-7018]

No

[credotim]

I am using flutter_local_notification and only onMessage.listen seems to be working for all 3 states foreground, background and terminated.

[jeffscaturro-aka]

A little later here, but this is most likely related to #6113.