How to handle the Firebase notification when app is in foreground

Solution 1:

When app is in foreground, notifications are not generated themselves. You need to write some additional code. When message is received onMessageReceived() method is called where you can generate the notification. Here is the code:

public class MyFirebaseMessagingService extends FirebaseMessagingService {
    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        super.onMessageReceived(remoteMessage);
        Log.d("msg", "onMessageReceived: " + remoteMessage.getData().get("message"));
        Intent intent = new Intent(this, MainActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_ONE_SHOT);
        String channelId = "Default";
        NotificationCompat.Builder builder = new  NotificationCompat.Builder(this, channelId)
                .setSmallIcon(R.mipmap.ic_launcher)
                .setContentTitle(remoteMessage.getNotification().getTitle())
                .setContentText(remoteMessage.getNotification().getBody()).setAutoCancel(true).setContentIntent(pendingIntent);;
        NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationChannel channel = new NotificationChannel(channelId, "Default channel", NotificationManager.IMPORTANCE_DEFAULT);
            manager.createNotificationChannel(channel);
        }
        manager.notify(0, builder.build());
    }
}

Solution 2:

FirebaseMessagingService never work when the app is in foreground. In this case if you want to receive the message from FCM then WakefulBroadcastReceiver will work for you

public class FirebaseDataReceiver extends WakefulBroadcastReceiver {


        @Override
        public void onReceive(Context context, Intent intent) {

            Log.d("BroadcastReceiver::", "BroadcastReceiver");
            NotificationCompat.Builder builder = new NotificationCompat.Builder(context)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle(intent.getExtras().getString("title"))
                    .setContentText(intent.getExtras().getString("message"));
            NotificationManager manager = (NotificationManager) context.getSystemService(NOTIFICATION_SERVICE);
            manager.notify(0, builder.build());
        }
    }

Link firebase with GCM in play store and write the below code in manifest

<receiver
    android:name=".firebase.FirebaseDataReceiver"
    android:exported="true"
    android:permission="com.google.android.c2dm.permission.SEND">
    <intent-filter>
        <action android:name="com.google.android.c2dm.intent.RECEIVE" />
    </intent-filter>
</receiver>