设备离线时仅收到一个 Firebase 通知 Flutter

Question

我在弄清楚如何通过 Flutter 上的 firebase 推送通知达到我想要的结果时遇到了一些麻烦。

基本上，我尝试在设备离线的情况下发送一组推送通知，然后我重新激活 wifi，但设备只收到一个通知。

我已经阅读了this，但我不知道如何接收所有通知并将其显示给用户。 基本上和whatsapp 一样。 文字

如果在通知消息中我设置了

notification

（带或不带

data

）键，则设备重新上线后只会收到一个通知。 如果在通知消息中我设置了

data

（没有

notification

），则无法设置标题和正文，因此不会向用户显示通知。

这是我用来处理 firebase 通知的代码：

import 'dart:convert';
import 'package:firebase_messaging/firebase_messaging.dart';
import 'package:flutter_local_notifications/flutter_local_notifications.dart';

Future handleBackgroundMessage(RemoteMessage message) async {
  print("Title: ${message.notification?.title}");
  print("Body: ${message.notification?.body}");
  print("Payload: ${message.data}");
}

class FirebaseApi {
  final _firebaseMessaging = FirebaseMessaging.instance;

  final _androidChannel = const AndroidNotificationChannel(
    'high_importance_channel',
    'High Importance Notifications',
    description: "This channel is used for important notifications",
    importance: Importance.defaultImportance,
  );

  final _localNotification = FlutterLocalNotificationsPlugin();

  void handleMessage(RemoteMessage? message) {
    if (message == null) return;
    print("Title: ${message.notification?.title}");
    print("Body: ${message.notification?.body}");
    print("Payload: ${message.data}");

    //action after the user tapped on the notification
  }

  Future initLocalNotifications() async {
    const iOS = DarwinInitializationSettings();
    const android = AndroidInitializationSettings("@drawable/ic_launcher");
    const settings = InitializationSettings(android: android, iOS: iOS);

    await _localNotification.initialize(settings,
        onDidReceiveNotificationResponse: (response) {
      final message = RemoteMessage.fromMap(jsonDecode(response.payload!));
      handleMessage(message);
    });

    final platform = _localNotification.resolvePlatformSpecificImplementation<
        AndroidFlutterLocalNotificationsPlugin>();
    await platform?.createNotificationChannel(_androidChannel);
  }

  Future initPushNotifications() async {
    await FirebaseMessaging.instance
        .setForegroundNotificationPresentationOptions(
            alert: true, badge: true, sound: true);

    FirebaseMessaging.instance.getInitialMessage().then(handleMessage);
    FirebaseMessaging.onMessageOpenedApp.listen(handleMessage);
    FirebaseMessaging.onBackgroundMessage(handleBackgroundMessage);
    FirebaseMessaging.onMessage.listen(
      (message) {
        final notification = message.notification;

        _localNotification.show(
          notification.hashCode,
          notification?.title ?? "Default title",
          notification?.body ?? "Default body",
          NotificationDetails(
            android: AndroidNotificationDetails(
                _androidChannel.id, _androidChannel.name,
                channelDescription: _androidChannel.description,
                icon: "@drawable/ic_launcher"),
          ),
          payload: jsonEncode(
            message.toMap(),
          ),
        );
      },
    );
  }

  Future<String?> initNotification() async {
    await _firebaseMessaging.requestPermission();
    String? fcmToken = await _firebaseMessaging.getToken();
    //log
    print(fcmToken);
    //start notifications
    initPushNotifications();
    initLocalNotifications();
    return fcmToken;
  }
}

任何帮助将不胜感激。

Answer 1

经过大量测试，我找到了一种解决方法，不知道这是否是最好的解决方案，但它工作正常。

我暂时只在 Android 上测试过。

基本上，我从我的 php 服务器将此负载发送到 Firebase V1 API：

{
   "message":{
      "token":"YOUR TOKEN",
      "data":{
         "title":"Title",
         "body":"Body"
      },
      "android":{
         "priority":"high"
      },
      "apns":{
         "headers":{
            "apns-priority":"10"
         }
      }
   }
}

通过省略

notification

标签，因为 firebase 文档显示“发送静默消息”并且通知不会出现在设备上，因此需要手动通知，在我的代码中我使用 flutter_local_notification 包。

@pragma('vm:entry-point')
Future handleBackgroundMessage(RemoteMessage message) async {
  /*print("background");
  print(message.toMap());*/
  try {
    FirebaseApi firebaseApi = FirebaseApi();
    await firebaseApi.initAndSendLocalNotification(message);
  } catch (e) {
    print(e);
  }
}

class FirebaseApi {
  final _androidChannel = const AndroidNotificationChannel(
    'high_importance_channel',
    'High Importance Notifications',
    description: "This channel is used for important notifications",
    importance: Importance.max,
  );

  final _localNotification = FlutterLocalNotificationsPlugin();

  void handleMessage(RemoteMessage? message) async {
    /*print("handle message");
    print(message?.toMap());*/
    if (message == null) return;
    //YOUR ACTION HERE
  }

  void handleInitialMessage(RemoteMessage? message) async {
    /*print("initial message");
    print(message?.toMap());*/
    if (message == null) return;
    //YOUR ACTION HERE
  }

  Future initLocalNotifications() async {
    const iOS = DarwinInitializationSettings();
    const android = AndroidInitializationSettings("@drawable/ic_launcher");
    const settings = InitializationSettings(android: android, iOS: iOS);

    await _localNotification.initialize(settings,
        onDidReceiveNotificationResponse: (response) {
      final message = RemoteMessage.fromMap(jsonDecode(response.payload!));
      handleMessage(message);
    });

    final appLaunchDetails =
        await _localNotification.getNotificationAppLaunchDetails();

    if (appLaunchDetails != null && appLaunchDetails.didNotificationLaunchApp) {
      if (appLaunchDetails.notificationResponse != null) {
        final message = RemoteMessage.fromMap(
            jsonDecode(appLaunchDetails.notificationResponse!.payload!));
        handleInitialMessage(message);
      }
    }

    final platform = _localNotification.resolvePlatformSpecificImplementation<
        AndroidFlutterLocalNotificationsPlugin>();
    await platform?.createNotificationChannel(_androidChannel);
  }

  initAndSendLocalNotification(RemoteMessage message) async {
    await initLocalNotifications();
    sendLocalNotification(message);
  }

  sendLocalNotification(RemoteMessage message) {
    final notification = message.data;
    _localNotification.show(
      message.hashCode,
      notification["title"],
      notification["body"],
      NotificationDetails(
        android: AndroidNotificationDetails(
            _androidChannel.id, _androidChannel.name,
            channelDescription: _androidChannel.description,
            icon: "@drawable/ic_launcher"),
      ),
      payload: jsonEncode(
        message.toMap(),
      ),
    );
  }

  Future initPushNotifications() async {
    await FirebaseMessaging.instance
        .setForegroundNotificationPresentationOptions(
            alert: true, badge: true, sound: true);

    //FirebaseMessaging.instance.getInitialMessage().then(handleInitialMessage);
    //FirebaseMessaging.onMessageOpenedApp.listen(handleBackgroundMessage);
    FirebaseMessaging.onBackgroundMessage(handleBackgroundMessage);
    FirebaseMessaging.onMessage.listen(
      (message) {
        //print(message.toMap());
        sendLocalNotification(message);
      },
    );
  }

  Future<String?> initNotification() async {
    final firebaseMessaging = FirebaseMessaging.instance;
    await firebaseMessaging.requestPermission();
    String? fcmToken = await firebaseMessaging.getToken();
    //start notifications
    initPushNotifications();
    initLocalNotifications();
    return fcmToken;
  }
}

通过这样做，前台、后台、终止状态应用程序通知都会得到正确处理，即使设备在离线时收到通知，一旦在线，所有通知都将发送到设备，因为 firebase 不会折叠待处理的通知。

希望它对某人有用。