Flutter 推送通知：无法在后台或应用程序关闭时接收通知

Question

我正在为 Android 和 iOS 开发一个 Flutter 应用程序。它有通知，所以我确实实现了firebase_messaging API。我正在通过设备 ID 向某些设备发送通知，并向topics其发送通知。

我正在测试topics通知发送，它在 Android 中 100% 正常工作。我按照上面提供的链接中的指南，也实现了 iOS 设置。但是在 iOS 中，当通知被发送时，只有当它在前台时才会被应用程序接收。这意味着，只能通过onMessage. 如果应用程序在后台或关闭，我看不到通知（我在控制台中打印它）。但是当我重新打开应用程序时，通知会被打印出来。

下面是我的通知注册码

    FirebaseMessagesImpl msg = FirebaseMessagesImpl();
         msg.requestPermissions();
    
    //Get configured with firebase messaging to recieve messages
    msg.getMessage().then((_) {
     msg.register().then((String token) {
     print(token);
    
     //Register to the `topic` so we get messages sent to the topic
     msg.topicRegister();
.........
}

FirebaseMessagesImpl

  import 'package:firebase_messaging/firebase_messaging.dart';

  import 'package:http/http.dart' as http;
  import 'dart:convert' as convert;

  class FirebaseMessagesImpl {
    final FirebaseMessaging _firebaseMessaging = FirebaseMessaging();

    String serverToken =
        "AAAAAAA:XXXXXXXXX-YYYYYYYY-ZZZZ-BBBBBBBB";

    Future<String> register() async {
      String token = "";
      _firebaseMessaging.getToken().then((t) {
        token = t;
        print("ha: " + t);
      });

      return token;
    }

    Future<void> getMessage() async {
      _firebaseMessaging.configure(
          onMessage: (Map<String, dynamic> message) async {
        print('on message $message');
        //setState(() => _message = message["notification"]["title"]);
      }, onResume: (Map<String, dynamic> message) async {
        print('on resume $message');
        // setState(() => _message = message["notification"]["title"]);
      }, onLaunch: (Map<String, dynamic> message) async {
        print('on launch $message');
        //setState(() => _message = message["notification"]["title"]);
      });
    }

    void topicRegister() {
    // _firebaseMessaging.subscribeToTopic("mobile_admin");
      _firebaseMessaging.subscribeToTopic("puppies");
    }



    void requestPermissions() async
    {
      await _firebaseMessaging.requestNotificationPermissions(
        const IosNotificationSettings(sound:true, badge:true, alert:true, provisional:false)
      );
    }

}

下面是我的Info.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>FirebaseAppDelegateProxyEnabled</key>
    <false/>
    <key>CFBundleDevelopmentRegion</key>
    <string>$(DEVELOPMENT_LANGUAGE)</string>
    <key>CFBundleExecutable</key>
    <string>$(EXECUTABLE_NAME)</string>
    <key>CFBundleIdentifier</key>
    <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
    <key>CFBundleInfoDictionaryVersion</key>
    <string>6.0</string>
    <key>CFBundleName</key>
    <string>MY APP NAME</string>
    <key>CFBundlePackageType</key>
    <string>APPL</string>
    <key>CFBundleShortVersionString</key>
    <string>$(FLUTTER_BUILD_NAME)</string>
    <key>CFBundleSignature</key>
    <string>????</string>
    <key>CFBundleVersion</key>
    <string>$(FLUTTER_BUILD_NUMBER)</string>
    <key>LSRequiresIPhoneOS</key>
    <true/>
    <key>UIBackgroundModes</key>
    <array>
        <string>fetch</string>
        <string>remote-notification</string>
    </array>
    <key>UILaunchStoryboardName</key>
    <string>LaunchScreen</string>
    <key>UIMainStoryboardFile</key>
    <string>Main</string>
    <key>UISupportedInterfaceOrientations</key>
    <array>
        <string>UIInterfaceOrientationPortrait</string>
        <string>UIInterfaceOrientationLandscapeLeft</string>
        <string>UIInterfaceOrientationLandscapeRight</string>
    </array>
    <key>UISupportedInterfaceOrientations~ipad</key>
    <array>
        <string>UIInterfaceOrientationPortrait</string>
        <string>UIInterfaceOrientationPortraitUpsideDown</string>
        <string>UIInterfaceOrientationLandscapeLeft</string>
        <string>UIInterfaceOrientationLandscapeRight</string>
    </array>
    <key>UIViewControllerBasedStatusBarAppearance</key>
    <false/>
</dict>
</plist>

下面是AppDelegate.swift

import UIKit
import Flutter
import Firebase

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    FirebaseApp.configure()
    GeneratedPluginRegistrant.register(with: self)
    if #available(iOS 10.0, *) {
      UNUserNotificationCenter.current().delegate = self as? UNUserNotificationCenterDelegate
    }
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
    
    override func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {

      Messaging.messaging().apnsToken = deviceToken
      super.application(application, didRegisterForRemoteNotificationsWithDeviceToken: deviceToken)
    }
}

正如某些人在 OTHER SO 答案中推荐的那样，我从 AppDelegate.swift 代码中删除了以下部分并尝试过，仍然存在相同的问题。

if #available(iOS 10.0, *) {
      UNUserNotificationCenter.current().delegate = self as? UNUserNotificationCenterDelegate
    }

我也cloud messaging按照指南将苹果密钥文件上传到 Firebase 项目部分。

下面是我发送通知的 JSon 代码

{
           "notification": {
              "body": "body",
              "title": "title"
           },
           "priority": "high",
           "data": {
            "body": "body",
              "title": "title",
              "click_action": "FLUTTER_NOTIFICATION_CLICK",
              "id": "1",
              "status": "done",
              "image": "https://ibin.co/2t1lLdpfS06F.png"
           },
           "to": "/topics/puppies"
        }

我的登录功能如下

我是 iOS 新手，无法弄清楚发生了什么。我想就像在 Android 中一样，当应用程序在后台或关闭时，通知会自动出现在通知栏中。

更新

根据@nandish 的建议，我将AppDelegate.swift文件更改如下

import UIKit
import Flutter
import Firebase

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate, UNUserNotificationCenterDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    FirebaseApp.configure()
    GeneratedPluginRegistrant.register(with: self)
    UNUserNotificationCenter.current().delegate = self
    
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
    
    override func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {

      Messaging.messaging().apnsToken = deviceToken
      super.application(application, didRegisterForRemoteNotificationsWithDeviceToken: deviceToken)
    }
    
    // MARK: - UNUserNotificationCenterDelegate Method
    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        completionHandler([.alert])
    }

    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {

     }
}

然后我结束了以下错误

UNUserNotificationCenter' is only available in iOS 10.0 or newer
        func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {

更新

在前台，当发出通知时，我从应用程序收到以下响应。这也仅在 iPhone 模拟器中，而不是在真实设备中。

{from: /topics/puppies, status: done, id: 1, notification: {body: body, title: title, e: 1, tag: topic_key_9204266xxxxxxx535}, title: title, image: https://ibin.co/2t1lLdpfS06F.png, collapse_key: com.aaa.xxx, body: body, click_action: FLUTTER_NOTIFICATION_CLICK}

Answer 1

首先，如果您使用 Firebase Cloud Messaging 进行通知，Android 将在应用程序打开或关闭时收到通知。但在 iOS 方面，iOS 使用的是APN's (Apple Push Notification).

*- 您应该在真实设备上尝试。在 iOS 模拟器上，获取通知不稳定。在 *

在您的 Firebase 控制台上，Settings > Cloud Messaging > iOS Application Configuration然后从 Apple Developer 面板添加您的 APN 识别密钥。你可以在这个文档上看到。

您还应该添加"content_available": true通知负载。

这里有一个例子：

{
  "to": "/topics/topic_name",
  "content_available": true,
  "notification": {
    "title": "TITLE TEXT",
    "body": "BODY TEXT",
    "content_available": true
  },
  "data": {
    "body": "BODY TEXT",
    "title": "TITLE TEXT",
    "click_action": "FLUTTER_NOTIFICATION_CLICK"
  }
}