前言：

我的应用程序是基于Flutter的-但需要本机代码实现才能使FCM消息工作，请参阅下文了解更多详细信息

GitHub issue#154供参考。

我在iOS上获得FCM通知时遇到了巨大的麻烦，特别是在我发布到Testflight的应用程序上。我在这个问题上被卡住了一个星期，完全不知道该怎么办。

问题

当使用Xcode/Android Studio在我的设备上使用调试/发布构建在本地运行时，会在后台、前台等接收到通知。当上传完全相同的应用程序到Testflight时，没有一个通知会通过FCM。

• 这是至关重要的，因为FCM提供VoIP通知，这些在Testflight上没有收到，这非常令人沮丧 *
  问题和解决方案？

我发现了两个问题（here和here），这两个问题似乎都表明这是一个APNS证书问题（APNS -> Firebase）。我已经重新创建了我的证书并将其添加到Firebase控制台（所有证书生成操作都使用相同的.csr文件）

设置/配置：
*APNS生成密钥并添加到Firebase
*功能：

尝试：

<key>FirebaseAppDelegateProxyEnabled</key>
<string>NO</string>

其中：

<key>FirebaseAppDelegateProxyEnabled</key>
<string>0</string>

并具有：

<key>FirebaseAppDelegateProxyEnabled</key>
<boolean>false</boolean>

*后台模式：

<key>UIBackgroundModes</key>
    <array>
        <string>audio</string>
        <string>bluetooth-central</string>
        <string>external-accessory</string>
        <string>fetch</string>
        <string>location</string>
        <string>processing</string>
        <string>remote-notification</string>
        <string>voip</string>
        <string>remote-notification</string>
    </array>

教程/来源：

• Setup FCM & APNS
• ConnectyCube P2P Session source
  Swift代码：（目标值>=10.0）

import UIKit
import CallKit
import Flutter
import Firebase
import UserNotifications
import GoogleMaps
import PushKit
import flutter_voip_push_notification
import flutter_call_kit

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate, PKPushRegistryDelegate {
    override func application(
        _ application: UIApplication,
        didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
    ) -> Bool {
        
        // run firebase app
        FirebaseApp.configure()
        
        // setup Google Maps
        GMSServices.provideAPIKey("google-maps-api-key")
        
        // register notification delegate
        UNUserNotificationCenter.current().delegate = self as UNUserNotificationCenterDelegate
        
        GeneratedPluginRegistrant.register(with: self)
        
        // register VOIP
        self.voipRegistration()
        
        // register notifications
        application.registerForRemoteNotifications();
        return super.application(application, didFinishLaunchingWithOptions: launchOptions)
    }
    
    // Handle updated push credentials
    public func pushRegistry(_ registry: PKPushRegistry, didUpdate pushCredentials: PKPushCredentials, for type: PKPushType) {
        // Process the received pushCredentials
        FlutterVoipPushNotificationPlugin.didUpdate(pushCredentials, forType: type.rawValue);
    }
    
    // Handle incoming pushes
    public func pushRegistry(_ registry: PKPushRegistry,
                             didReceiveIncomingPushWith payload: PKPushPayload,
                             for type: PKPushType,
                             completion: @escaping () -> Swift.Void){
        
        FlutterVoipPushNotificationPlugin.didReceiveIncomingPush(with: payload, forType: type.rawValue)
        
        let signalType = payload.dictionaryPayload["signal_type"] as! String
        if(signalType == "endCall" || signalType == "rejectCall"){
            return
        }
        
        let uuid = payload.dictionaryPayload["session_id"] as! String
        let uID = payload.dictionaryPayload["caller_id"] as! Int
        let callerName = payload.dictionaryPayload["caller_name"] as! String
        let isVideo = payload.dictionaryPayload["call_type"] as! Int == 1;
        FlutterCallKitPlugin.reportNewIncomingCall(
            uuid,
            handle: String(uID),
            handleType: "generic",
            hasVideo: isVideo,
            localizedCallerName: callerName,
            fromPushKit: true
        )
        completion()
    }
    
    // Register for VoIP notifications
    func voipRegistration(){
        // Create a push registry object
        let voipRegistry: PKPushRegistry = PKPushRegistry(queue: DispatchQueue.main)
        // Set the registry's delegate to self
        voipRegistry.delegate = self
        // Set the push type to VoIP
        voipRegistry.desiredPushTypes = [PKPushType.voIP]
    }
}

public func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
    if #available(iOS 14.0, *) {
        completionHandler([ .banner, .alert, .sound, .badge])
    } else {
        completionHandler([.alert, .sound, .badge])
    }
}

func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
    print(deviceToken)
    Messaging.messaging().apnsToken = deviceToken;
}

Fluttermain.dart

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  await initializeDateFormatting();
  setupLocator();
  var fcmService = locator<FCMService>();

  FirebaseMessaging.onBackgroundMessage(FCMService.handleFirebaseBackgroundMessage);
  FirebaseMessaging.onMessage.listen((event) {
    print("Foreground message");
    Fluttertoast.showToast(msg: "Received onMessage event");
    FCMService.processCallNotification(event.data);
  });
  FirebaseMessaging.onMessageOpenedApp.listen((event) {
    print("On message opened app");
    Fluttertoast.showToast(msg: "Received onMessageOpenedAppEvent");
    FCMService.handleInitialMessage(event);
  });
  FirebaseMessaging.instance.getInitialMessage().then((value) {
    Fluttertoast.showToast(msg: "Received onLaunch event");
    if (value != null) {
      FCMService.handleInitialMessage(value);
    }
  });

  initConnectyCube();
  runApp(AppProviders());
}

FCMService.dart

// handle any firebase message
  static Future<void> handleFirebaseBackgroundMessage(RemoteMessage message) async {
    print("Received background message");
    Fluttertoast.showToast(msg: "Received Firebase background message");
    await Firebase.initializeApp();
    setupLocator();
    var fcmService = locator<FCMService>();
    fcmService.init();

    _handleMessage(message, launchMessage: true);
  }

测试：

测试是在2个物理iPhone（6s和8）上完成的。当使用（调试和发布）模式直接从Mac（Android Studio和XCode）构建时，两者都可以使用Firebase FCM。当从TestFlight下载相同的内容时，两者都不起作用。
如果任何人可以提供对错误配置，设置错误或缺少/不正确的Swift代码的洞察，或者只是错误或遗漏，我们将不胜感激。