Firebase onMessageReceived not called when app in

Question

I'm working with Firebase and testing sending notifications to my app from my server while the app is in the background. The notification is sent successfully, it even appears on the notification centre of the device, but when the notification appears or even if I click on it, the onMessageReceived method inside my FCMessagingService is never called.

When I tested this while my app was in the foreground, the onMessageReceived method was called and everything worked fine. The problem occurs when the app is running in the background.

Is this intended behaviour, or is there a way I can fix this?

Here is my FBMessagingService:

import android.util.Log;

import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;

public class FBMessagingService extends FirebaseMessagingService {

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        Log.i("PVL", "MESSAGE RECEIVED!!");
        if (remoteMessage.getNotification().getBody() != null) {
            Log.i("PVL", "RECEIVED MESSAGE: " + remoteMessage.getNotification().getBody());
        } else {
            Log.i("PVL", "RECEIVED MESSAGE: " + remoteMessage.getData().get("message"));
        }
    }
}

Answer 1

By default the Launcher Activity in you app will be launched when your app is in background and you click the notification, if you have any data part with your notifcation you can handle it in the same activity as follows,

if(getIntent().getExtras()! = null){
  //do your stuff
}else{
  //do that you normally do
}

Answer 2

I was having the same issue and did some more digging on this. When the app is in the background, a notification message is sent to the system tray, BUT a data message is sent to onMessageReceived()
See https://firebase.google.com/docs/cloud-messaging/downstream#monitor-token-generation_3
and https://github.com/firebase/quickstart-android/blob/master/messaging/app/src/main/java/com/google/firebase/quickstart/fcm/MyFirebaseMessagingService.java

To ensure that the message you are sending, the docs say, "Use your app server and FCM server API: Set the data key only. Can be either collapsible or non-collapsible."
See https://firebase.google.com/docs/cloud-messaging/concept-options#notifications_and_data_messages

Answer 3

Just override the OnCreate method of FirebaseMessagingService. It is called when your app is in background:

public override void OnCreate()
{
    // your code
    base.OnCreate();
}

Answer 4

Remove notification field completely from your server request. Send only data and handle it in onMessageReceived() otherwise your onMessageReceived() will not be triggered when app is in background or killed.

Don't forget to include "priority": "high" field in your notification request. According to the documentation: data messages are sent with a normal priority, thus they will not arrive instantly; it could also be the problem.

Here is what I am sending from server

{
  "data":{
    "id": 1,
    "missedRequests": 5
    "addAnyDataHere": 123
  },
  "to": "fhiT7evmZk8:APA91bFJq7Tkly4BtLRXdYvqHno2vHCRkzpJT8QZy0TlIGs......",
  "priority": "high"
}

So you can receive your data in onMessageReceived(RemoteMessage message) like this....let say I have to get id

Object obj = message.getData().get("id");
        if (obj != null) {
            int id = Integer.valueOf(obj.toString());
        }

Answer 5

There are two types of messages: notification messages and data messages. If you only send data message, that is without notification object in your message string. It would be invoked when your app in background.

Answer 6

I had the same problem. It is easier to use the 'data message' instead of the 'notification'. The data message always load the class onMessageReceived.

In that class you can make your own notification with the notificationbuilder.

Example:

 @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        sendNotification(remoteMessage.getData().get("title"),remoteMessage.getData().get("body"));
    }

    private void sendNotification(String messageTitle,String messageBody) {
        Intent intent = new Intent(this, MainActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this,0 /* request code */, intent,PendingIntent.FLAG_UPDATE_CURRENT);

        long[] pattern = {500,500,500,500,500};

        Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

        NotificationCompat.Builder notificationBuilder = (NotificationCompat.Builder) new NotificationCompat.Builder(this)
                .setSmallIcon(R.drawable.ic_stat_name)
                .setContentTitle(messageTitle)
                .setContentText(messageBody)
                .setAutoCancel(true)
                .setVibrate(pattern)
                .setLights(Color.BLUE,1,1)
                .setSound(defaultSoundUri)
                .setContentIntent(pendingIntent);

        NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
    }