Firebase 消息在应用程序在后台和前台运行时有效。 但是，当应用程序终止时没有通知

Question

I am new to flutter and firebase and have followed the documentation best I could. FCM seems to work when the app is in the foreground and background. However, when the app is terminated I do not get any notifications. I have looked at the app permissions etc and all seem to be fine.

pubspec.yml firebase_messaging: ^11.2.5

class PushNotificationService {
  final FirebaseMessaging messaging = FirebaseMessaging.instance;

  Future initialize() async {

    NotificationSettings settings = await messaging.requestPermission(
      alert: true,
      announcement: false,
      badge: true,
      carPlay: false,
      criticalAlert: false,
      provisional: false,
      sound: true,
    );


    if (settings.authorizationStatus == AuthorizationStatus.authorized) {
      print('User granted permission');
    } else if (settings.authorizationStatus == AuthorizationStatus.provisional) {
      print('User granted provisional permission');
    } else {
      print('User declined or has not accepted permission');
    }

    FirebaseMessaging.onMessage.listen((RemoteMessage message) {
      print('Got a message whilst in the foreground!');
      print('Message data: ${message.data}');

      if (message.notification != null) {
        print('Message also contained a notification: ${message.notification}');
      }
    });
  }
}

main.dart

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




Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(
    options: const FirebaseOptions(
      apiKey: "",
      authDomain: '',
      databaseURL: "",
      projectId: "",
      storageBucket: "",
      messagingSenderId: '',
      appId: "",
      measurementId: '',
    ),
  );

  FirebaseMessaging.onBackgroundMessage(_firebaseMessagingBackgroundHandler);

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

  final FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin =
  FlutterLocalNotificationsPlugin();

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

  runApp(MyApp());
}

home.dart

class _HomeTabState extends State<HomeTab> {


  void pushnotifications()async{
    PushNotificationService pushNotificationService=PushNotificationService();
    pushNotificationService.initialize();
    pushNotificationService.getToken();
  }




  @override
  void initState() {
    // TODO: implement initState
    super.initState();
    pushnotifications();

  }

@override
  Widget build(BuildContext context) {
    return Scaffold(
        body: Container(
    ));
  }

Androidmanifest

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com">

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <uses-permission android:name="android.permission.INTERNET"/>


   <application
        android:label=""
        android:name="${applicationName}"
        android:icon="@mipmap/ic_launcher">
             <meta-data
              android:name="io.flutter.embedding.android.NormalTheme"
              android:resource="@style/NormalTheme"
              />
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
            <intent-filter>
                <action android:name="FLUTTER_NOTIFICATION_CLICK"/>
                <category android:name="android.intent.category.DEFAULT"/>
            </intent-filter>

        </activity>
        <!-- Don't delete the meta-data below.
             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
        <meta-data
            android:name="flutterEmbedding"
            android:value="2" />

       <meta-data android:name="com.google.android.geo.API_KEY"
           android:value=""/>

       <meta-data
           android:name="com.google.firebase.messaging.default_notification_channel_id"
           android:value="high_importance_channel" />
    </application>
</manifest>

Json Payload

{
    "to": "",
    "notification": {
        "body": "This is the body",
        "title": "This is the title"
    },
    "priority": "high"
}

Answer 1

You should probably also add a listener for getInitialMessage() on firebase message instance. This will fetch the notifications when app is terminated.

FirebaseMessaging.instance
        .getInitialMessage()
        .then((RemoteMessage? message) {
      if (message != null) {
        Navigator.pushNamed(
          context,
          '/message',
          arguments: MessageArguments(message, true),
        );
      }
    });

Refer: https://pub.dev/packages/firebase_messaging/example