Unhandled Exception: setState() called after dispose() - flutter

Question

I am trying to receive notifications in my flutter app using Firebase Messaging to display them in the app, but I keep getting the error:
/FLTFireMsgReceiver( 6823): broadcast received for message
E/flutter ( 6823): [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: setState() called after dispose(): _TipsState#aa4df(lifecycle state: defunct, not mounted)
E/flutter ( 6823): This error happens if you call setState() on a State object for a widget that no longer appears in the widget tree (e.g., whose parent widget no longer includes the widget in its build). This error can occur when code calls setState() from a timer or an animation callback.
E/flutter ( 6823): The preferred solution is to cancel the timer or stop listening to the animation in the dispose() callback. Another solution is to check the "mounted" property of this object before calling setState() to ensure the object is still in the tree.
E/flutter ( 6823): This error might indicate a memory leak if setState() is being called because another object is retaining a reference to this State object after it has been removed from the tree. To avoid memory leaks, consider breaking the reference to this object during dispose().
E/flutter ( 6823): #0 State.setState.<anonymous closure> (package:flutter/src/widgets/framework.dart:1085:9)
E/flutter ( 6823): #1 State.setState (package:flutter/src/widgets/framework.dart:1120:6)
E/flutter ( 6823): #2 _TipsState.getNotification.<anonymous closure> (package:stock_baba/Screens/Tips.dart:38:9)
E/flutter ( 6823): #3 _rootRunUnary (dart:async/zone.dart:1434:47)
E/flutter ( 6823): #4 _CustomZone.runUnary (dart:async/zone.dart:1335:19)
E/flutter ( 6823): #5 _CustomZone.runUnaryGuarded (dart:async/zone.dart:1244:7)
E/flutter ( 6823): #6 _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:341:11)
E/flutter ( 6823): #7 _DelayedData.perform (dart:async/stream_impl.dart:591:14)
E/flutter ( 6823): #8 _StreamImplEvents.handleNext (dart:async/stream_impl.dart:706:11)
E/flutter ( 6823): #9 _PendingEvents.schedule.<anonymous closure> (dart:async/stream_impl.dart:663:7)
E/flutter ( 6823): #10 _rootRun (dart:async/zone.dart:1418:47)
E/flutter ( 6823): #11 _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter ( 6823): #12 _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
E/flutter ( 6823): #13 _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1276:23)
E/flutter ( 6823): #14 _rootRun (dart:async/zone.dart:1426:13)
E/flutter ( 6823): #15 _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter ( 6823): #16 _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
E/flutter ( 6823): #17 _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1276:23)
E/flutter ( 6823): #18 _microtaskLoop (dart:async/schedule_microtask.dart:40:21)
E/flutter ( 6823): #19 _startMicrotaskLoop (dart:async/schedule_microtask.dart:49:5)
The PushNotification class is a simple class with the string fields title, body, dataTitle and dataBody.
My code is as follows:
class _TipsState extends State<Tips> {
final FirebaseMessaging _firebaseMessaging = FirebaseMessaging.instance;
final List<PushNotification> messages = [];
PushNotification? _notificationInfo;
#override
void initState() {
getNotification();
super.initState();
}
void getNotification() async {
NotificationSettings settings =
await _firebaseMessaging.requestPermission();
if (settings.authorizationStatus == AuthorizationStatus.authorized) {
print("Permission granted!");
FirebaseMessaging.onMessage.listen((RemoteMessage message) {
PushNotification notification = PushNotification(
title: message.notification?.title,
body: message.notification?.body,
dataTitle: message.data['title'],
dataBody: message.data['body']);
setState(() {
_notificationInfo = notification;
});
if (notification != null) {
showSimpleNotification(Text(_notificationInfo!.title!),
duration: Duration(seconds: 2),
subtitle: Text(_notificationInfo!.body!));
}
print(notification);
print(message.data);
});
} else {
print("Permission declined!");
}
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: messages.isEmpty
? Container()
: ListView(
children: [Text(messages[0].title!)],
),
);
}
}
I tried wrapping my setState() with mounted() but it didn't work.
How can I resolve this issue and display the incoming notifications in my app?

Answer 1

Cancel the Stream after dispose it
Create StreamSubscription variable
StreamSubscription messagingSubscription;
Assign variable to your listen
....
messagingSubscription = FirebaseMessaging.onMessage.listen((RemoteMessage message) {
Dispose your StreamSubscription
#override
void dispose() {
messagingSubscription?.cancel();
super.dispose();
}

Answer 2

here is my code and its in working ..copy the code and make a dart class and paste it . your notification start working
use there plugins
firebase_core: ^1.11.0
firebase_messaging: ^11.2.5
flutter_local_notifications: ^9.2.0
import 'dart:convert';
import 'dart:math';
import 'package:firebase_core/firebase_core.dart';
import 'package:firebase_messaging/firebase_messaging.dart';
import 'package:flutter_local_notifications/flutter_local_notifications.dart';
import 'package:vcare/firebase_options.dart';
class NotificationHelper {
NotificationDetails get _ongoing {
const androidChannelSpecifics = AndroidNotificationDetails(
'customer-channel-id',
'customer-channel-name',
importance: Importance.max,
priority: Priority.high,
ongoing: false,
autoCancel: true,
);
const iOSChannelSpecifics = IOSNotificationDetails();
return const NotificationDetails(android: androidChannelSpecifics, iOS: iOSChannelSpecifics);
}
// Future<void> _firebaseMessagingBackgroundHandler(RemoteMessage message) async {
// If you're going to use other Firebase services in the background, such as Firestore,
// make sure you call `initializeApp` before using other Firebase services.
// await initFirebase();
// }
configure() async {
await initFirebase();
FirebaseMessaging messaging = FirebaseMessaging.instance;
await requestPermission(messaging);
final String? token = await messaging.getToken();
// FirebaseMessaging.onBackgroundMessage(_firebaseMessagingBackgroundHandler);
final notification = await setupLocalNotification();
FirebaseMessaging.onMessage.listen((RemoteMessage message) {
showNotification(
notification,
title: message.notification?.title,
body: message.notification?.body,
payload: message.data,
type: _ongoing,
);
});
return token;
}
Future<void> requestPermission(FirebaseMessaging messaging) async {
await messaging.requestPermission(
alert: true,
announcement: false,
badge: true,
carPlay: false,
criticalAlert: false,
provisional: false,
sound: true,
);
}
Future<void> initFirebase() async {
await Firebase.initializeApp(
options: DefaultFirebaseOptions.currentPlatform,
);
}
setupLocalNotification() async {
const AndroidInitializationSettings initializationSettingsAndroid = AndroidInitializationSettings(
'notification_icon',
);
final IOSInitializationSettings initializationSettingsIOS = IOSInitializationSettings(
onDidReceiveLocalNotification: (int id, String? title, String? body, String? payload) {},
);
final InitializationSettings initializationSettings = InitializationSettings(
android: initializationSettingsAndroid,
iOS: initializationSettingsIOS,
);
var notification = FlutterLocalNotificationsPlugin();
await notification.initialize(initializationSettings, onSelectNotification: (_) {});
return notification;
}
showNotification(FlutterLocalNotificationsPlugin notifications,
{required String? title, required String? body, required NotificationDetails type, required payload}) {
notifications.show(Random().nextInt(100), title, body, type, payload: json.encode(payload ?? {}));
}
}
and then call this class in main.dart file here is the code
WidgetsFlutterBinding.ensureInitialized();
String? token = await NotificationHelper().configure();
_storeFCMToken(token);
print("deviceToken $token");
if you find any problem please let me know. if you find this code is helping you .then please mark my answer as accepted