initialize method
Call this in your FirebaseService.init() after Firebase is initialized.
Implementation
Future<void> initialize(BuildContext context) async {
_messaging = FirebaseMessaging.instance;
await _requestPermissions();
await _setupLocalNotificationChannel();
await _setupFlutterLocalNotificationsPlugin();
await _setForegroundPresentationOptions();
await generateDeviceToken();
_listenForegroundNotifications();
_listenBackgroundAndTerminatedNotifications();
}