Flutter Firebase push notifications

Firbase:

1. Add firebase dependencies in flutter project pubspec.yaml file
   firebase_core: ^1.2.0
   firebase_messaging: ^10.0.0
   flutter_local_notifications: ^5.0.0+4

2. Get FCM token that is unique for device and app
   String token = await FirebaseMessaging.instance.getToken();

   • Store token in shared pref, to easy access from anywhere

3. Write background handler

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

4. Register above handler to firebase instance
   FirebaseMessaging.onBackgroundMessage(firebaseMessagesBackgroundHandler);

5. Create a android channel for android 8+

 AndroidNotificationChannel channel = AndroidNotificationChannel(
      'high_importance_channel', // id
      'High Importance Notifications', // title
      'This channel is used for important notifications.', // description
      importance: Importance.high,
    );
 

6. Create flutter local notification plugin for notification alert
   FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin = FlutterLocalNotificationsPlugin();

7. register android channel with flutter local notification plugin object

 	await flutterLocalNotificationsPlugin
        .resolvePlatformSpecificImplementation<
            AndroidFlutterLocalNotificationsPlugin>()
        ?.createNotificationChannel(channel);
 

8. Write foreground handler

 Future<void> firebaseMessagesForeGroundHandler(RemoteMessage message) async {

	} 

9. register foreground handler to FCM

 	FirebaseMessaging.onMessage.listen((RemoteMessage message) {
      firebaseMessagesForeGroundHandler(message);
    });
 

10. Init android, ios settings

 AndroidInitializationSettings initializationSettingsAndroid = AndroidInitializationSettings('ic_notifications');
		IOSInitializationSettings initializationSettingsIOS = IOSInitializationSettings( requestSoundPermission: false, requestBadgePermission: false, requestAlertPermission: false);
 

11. Add above settings to flutterLocalNotificationsPlugin

 final InitializationSettings initializationSettings = InitializationSettings(
	    android: initializationSettingsAndroid,
	    iOS: initializationSettingsIOS,
	  );
	  flutterLocalNotificationsPlugin.initialize(
	    initializationSettings,
	    onSelectNotification: onSelectNotification,
	  ); 

12. Show notification

 flutterLocalNotificationsPlugin.show(
        notification.hashCode,
        notification.title,
        notification.body,
        NotificationDetails(
          android: AndroidNotificationDetails(
            channel.id,
            channel.name,
            channel.description,
            icon: 'launch_background',
          ),
        ));