Flutter firebase 消息传递中的双重通知

最近我升级到 firebase_messaging: ^10.0.0 当应用程序未运行时，如果收到通知，它会显示两次。我收到后在代码中修改了通知数据并显示了它。即使如此，我也可以看到已修改和未修改的通知。我不知道该通知在哪里触发。但是当应用程序运行时，它仅显示一次通知（工作正常）。这是我的代码

/*main.dart*/
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 Firebase.initializeApp();

  // await HomePageState.handleMessage(message);
  String title="${message.notification!.title}";
  String body="${message.notification!.body}";

  _flutterLocalNotificationsPlugin.show(0, title, body, platformChannelSpecifics, payload: jsonEncode(message.data));

  AppDatabase database= await $FloorAppDatabase.databaseBuilder(Constants.dataBaseName).addMigrations([migration1to2]).build();
  if(!title.toLowerCase().contains("cancelled")){
    var date=DateFormat("dd-MMM-yyyy hh:mm aa").format(DateTime.now());
    NotificationModel notification=NotificationModel(title: title,message: body,read: 0,date: date);
    await database.notificationDao.insertNotification(notification);
  }

  print("Handling a background message: ${message.messageId}");
}
Future<void> main() async {
  //this line make sure all the required widgets are loaded before main application starts
  //SharedPreferences.setMockInitialValues({});
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();

  var initializationSettingsAndroid = new AndroidInitializationSettings('@mipmap/ic_notification');
  var initializationSettingsIOS = new IOSInitializationSettings(onDidReceiveLocalNotification: onDidReceiveLocalNotification);
  //var initializationSettings = new InitializationSettings(initializationSettingsAndroid, initializationSettingsIOS);
  var initializationSettings = new InitializationSettings(android: initializationSettingsAndroid,iOS: initializationSettingsIOS);
  _flutterLocalNotificationsPlugin.initialize(initializationSettings,onSelectNotification: onSelectingNotification);

  FirebaseMessaging.onBackgroundMessage(firebaseMessagingBackgroundHandler);


  //Initializing repository and carrying forward to avoid multiple instances of database
  Repository _repository = Repository();

  // runApp(BlocProvider(
  //   create: (_) => ThemeBloc()..add(ThemeLoadStarted()),
  //   child: MyApp(
  //     repository: _repository,
  //   ),
  // ));
  SentryOptions options=SentryOptions(dsn: APIs.sentryAPI);
  final SentryClient _sentry = SentryClient(options);

  Future<void> _reportErrorToSentry(dynamic error, dynamic stackTrace) async {
    // Print the exception to the console.
    print('Caught error: $error');
   await  _sentry.captureException(
      error,
      stackTrace: stackTrace,
    );
  }

  runZonedGuarded(() async{
    // runApp(BlocProvider(
    //   create: (_) => ThemeBloc()..add(ThemeLoadStarted()),
    //   child: MyApp(
    //     repository: _repository,
    //   ),
    // ));

    await SentryFlutter.init(
          (options) => options.dsn = APIs.sentryAPI,
      appRunner: () => runApp(BlocProvider(
        create: (_) => ThemeBloc()..add(ThemeLoadStarted()),
        child: MyApp(
          repository: _repository,
        ),
      )),
    );
  }, (error, stackTrace) {
    print('runZonedGuarded: Caught error in my root zone.');
    FirebaseCrashlytics.instance.recordError(error, stackTrace);
    _reportErrorToSentry(error,stackTrace);
  });

}

应用程序.kt

import io.flutter.app.FlutterApplication
import io.flutter.plugin.common.PluginRegistry
import io.flutter.plugin.common.PluginRegistry.PluginRegistrantCallback
import io.flutter.plugins.GeneratedPluginRegistrant
import io.flutter.plugins.firebase.messaging.FlutterFirebaseMessagingBackgroundService


class Application : FlutterApplication(), PluginRegistrantCallback {

    override fun registerWith(registry: PluginRegistry) {
        //FirebaseCloudMessagingPluginRegistrant.registerWith(registry)
        FlutterLocalNotificationPluginRegistrant.registerWith(registry)
        SqflitePluginRegistrant.registerWith(registry)
    }
}

FirebaseCloudMessagingPluginRegistrant.kt 我在 application.kt 中注释掉了

import io.flutter.plugin.common.PluginRegistry
import io.flutter.plugins.firebase.messaging.FlutterFirebaseMessagingPlugin
class FirebaseCloudMessagingPluginRegistrant {
    companion object {
        fun registerWith(registry: PluginRegistry) {
            if (alreadyRegisteredWith(registry)) {
                return
            }
            FlutterFirebaseMessagingPlugin.registerWith(registry.registrarFor("io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin"))
        }

        fun alreadyRegisteredWith(registry: PluginRegistry): Boolean {
            val key = FirebaseCloudMessagingPluginRegistrant::class.java.name
            if (registry.hasPlugin(key)) {
                return true
            }
            registry.registrarFor(key)
            return false
        }
    }
}

AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="**.***.***tomer">
    <!-- io.flutter.app.FlutterApplication is an android.app.Application that
         calls FlutterMain.startInitialization(this); in its onCreate method.
         In most cases you can leave this as-is, but you if you want to provide
         additional functionality it is fine to subclass or reimplement
         FlutterApplication and put your custom class here. -->

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<!--    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />-->
<!--    android:label="@string/app_label"-->
    <application
        android:name=".Application"
        android:label="Zuzu"
        android:usesCleartextTraffic="true"
        android:networkSecurityConfig="@xml/network_security_config"
        android:icon="@mipmap/ic_launcher">
        <meta-data android:name="io.flutter.network-policy"
            android:resource="@xml/network_security_config"/>
        <activity
            android:name=".MainActivity"
            android:launchMode="singleTop"
            android:theme="@style/LaunchTheme"
            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
            android:hardwareAccelerated="true"
            android:windowSoftInputMode="adjustResize"
            tools:targetApi="n">

            <!-- Specifies an Android theme to apply to this Activity as soon as
                 the Android process has started. This theme is visible to the user
                 while the Flutter UI initializes. After that, this theme continues
                 to determine the Window background behind the Flutter UI. -->
            <meta-data
              android:name="io.flutter.embedding.android.NormalTheme"
              android:resource="@style/NormalTheme"
              />
            <!-- Displays an Android View that continues showing the launch screen
                 Drawable until Flutter paints its first frame, then this splash
                 screen fades out. A splash screen is useful to avoid any visual
                 gap between the end of Android's launch screen and the painting of
                 Flutter's first frame. -->
            <meta-data
              android:name="io.flutter.embedding.android.SplashScreenDrawable"
              android:resource="@drawable/launch_background"
              />

            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </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="AIzaSyBqZ4aa************GMzHpofWKeEU"/>
        <meta-data android:name="com.facebook.sdk.ApplicationId" android:value="@string/facebook_app_id"/>

        <meta-data
            android:name="com.google.firebase.messaging.default_notification_channel_id"
            android:value="Zuzu" />
        <meta-data android:name="com.google.firebase.messaging.default_notification_icon"
            android:resource="@mipmap/ic_notification"/>
        <meta-data android:name="com.google.firebase.messaging.default_notification_color"
            android:resource="@color/notification"/>

        <activity
            android:name="com.yalantis.ucrop.UCropActivity"
            android:screenOrientation="portrait"
            android:theme="@style/Theme.AppCompat.Light.NoActionBar"/>
    </application>
</manifest>

This issue is in android only that too when app is not running. Where am I doing wrong?

当您应该发送“数据”消息时，您似乎正在从 Firebase Messaging 发送“通知”消息。

下面是通知消息和数据消息的区别：

通知消息

FCM 自动代表最终用户设备显示消息 客户端应用程序的。

数据信息

客户端应用程序负责处理数据消息。

关于 FCM 消息 | Firebase（#消息类型） https://firebase.google.com/docs/cloud-messaging/concept-options#notifications_and_data_messages

这解释了为什么您会获得通知的未修改版本（这是来自通知消息的自动显示）和通知的修改版本（这是来自您处理通知的代码）。

解决方案：

您需要从后端发送数据消息。 因此，如果您之前将其作为通知负载：

{
  "message":{
    "token":"bk3RNwTe3H0:CI2k_HHwgIpoDKCIZvvDMExUdFQ3P1...",
    "notification":{
      "Nick" : "Mario",
      "body" : "great match!",
      "Room" : "PortugalVSDenmark"
    }
  }
}

你应该将其更改为：

{
  "message":{
    "token":"bk3RNwTe3H0:CI2k_HHwgIpoDKCIZvvDMExUdFQ3P1...",
    "data":{
      "Nick" : "Mario",
      "body" : "great match!",
      "Room" : "PortugalVSDenmark"
    }
  }
}