🐛 [firebase_messaging] FirebaseMessaging.onMessageOpenedApp.listen not working

[AgungLaksana]

I am using firebase_messaging: ^10.0.1 and firebase_core: ^1.2.0 and also Flutter (Channel stable, 2.2.1)

I want if my user click the notification then I will open a specific page. so I have code like this in my HomePage

class _HomePageState extends State<HomePage> {
  @override
  void initState() {
    super.initState();

    FirebaseMessaging.onMessageOpenedApp.listen((RemoteMessage message) {
      print('FCM Notification clicked!');
      // do something after user click the notification
    });
    
  }
}

Expected behavior

I expect that print('FCM Notification clicked!'); will show after I click the push notification from the notification tray, but it seems this FirebaseMessaging.onMessageOpenedApp.listen never triggered after clicking the push notification.

I test it using real device (Redmi Note 7 and Samsung SM J200G) in debug mode but that stream never triggered

Flutter doctor

[✓] Flutter (Channel stable, 2.2.1, on macOS 11.2.1 20D74 darwin-x64, locale en-ID)
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
[✓] Xcode - develop for iOS and macOS
[✓] Chrome - develop for the web
[✓] Android Studio (version 4.2)
[✓] VS Code (version 1.56.2)
[✓] Connected device (4 available)

• No issues found!

[erikkubica]

Same here #6255 I tried older/newer version of the flutter core and firebase messaging package and no luck. I noticed a weird thing about it, that when app is in background, I receive two notifications. From those two notifications, only one executes the onMessageOpenedApp

[yadav-aniket]

hey @AgungLaksana I was facing the same issue , here is what I did to resolve it for notification when app is in background

this is code snippet from firebase_messaging doc

Future _firebaseMessagingBackgroundHandler(RemoteMessage message) async {
await Firebase.initializeApp(); //
await FirebaseMessaging.instance.getToken(); // add this line
print('Handling a background message ${message.messageId}');
}

or

Future _firebaseMessagingBackgroundHandler(RemoteMessage message) async {
// remove await Firebase.initializeApp();
print('Handling a background message ${message.messageId}');
}

[markusaksli-nc]

Hi @AgungLaksana
Are you tapping on the notification received from FCM or are you using flutter_local_notifications in any way?
I'm not seeing this issue with the official example when tapping a notification (that isn't displayed by the local notification channel).
Thank you

[AgungLaksana]

@markusaksli-nc I am trying to follow the official example from here https://pub.dev/packages/firebase_messaging/example

it seems to me that both FirebaseMessaging.onBackgroundMessage and FirebaseMessaging.onMessage use FlutterLocalNotificationsPluginto display the notification. so both foreground and background from that example code will use flutter local notification right?

so I have problem when tapping a notification from flutter_local_notifications

[AgungLaksana]

@markusaksli-nc you are right, If I send FCM message using Firebase console to send Notification only message (not data) then FirebaseMessaging.onMessageOpenedApp.listen will be triggered

but If send data message payload from my own backend and then show it using flutter_local_notifications then FirebaseMessaging.onMessageOpenedApp.listen won't be triggered if I click it

[markusaksli-nc]

Well, then the issue is just that you need to use the callbacks for the local notification for getting tap events for the local notification. You should be able to find out how to do this from the flutter_local_notifications example.

https://github.com/MaikuB/flutter_local_notifications/blob/master/flutter_local_notifications/example/lib/main.dart

It all just depends on how you want to do things however, I do suggest that you read through the FCM API and see if you can use the remote message android payload options to do whatever you are doing with the data-only message spawning a local notification.

https://firebase.google.com/docs/reference/fcm/rest/v1/projects.messages#androidnotification

If you try to process the silent remote notification to display a local notification it seems like you are adding an unnecessary step that will lead to issues like this (unless you absolutely need to for some reason).