Xamarin Firebase iOS 11未生成FCM令牌

我的应用程序向firebase注册推送通知，接收令牌，然后将该令牌作为webview加载的url的查询字符串参数提供

尽管代码执行且未报告任何故障，但在iOS 11中令牌始终为空

下面的代码在远程模拟器或安装在设备上的iOS v9.x上工作，但在iOS v11.x运行时，这两种环境都不工作

有人经历过吗？有人有有用的建议吗？提前谢谢你的帮助，我正在把我剩下的头发拔出来

我正在使用以下软件包/版本：

Xamarin.Firebase.iOS.CloudMessaging v2.0.4.1 Xamarin.Firebase.iOS.Core v4.0.13 Xamarin.Firebase.iOS.InstanceId v2.0.8 从AppDelegate.cs：

    public override bool FinishedLaunching (UIApplication application, NSDictionary launchOptions)
    {
        // Override point for customization after application launch.
        // If not required for your application you can safely delete this method

        // Register your app for remote notifications.
        if (UIDevice.CurrentDevice.CheckSystemVersion(10, 0))
        {
            // iOS 10 or later
            var authOptions = UNAuthorizationOptions.Alert | UNAuthorizationOptions.Badge | UNAuthorizationOptions.Sound;
            UNUserNotificationCenter.Current.RequestAuthorization(authOptions, (granted, error) =>
            {
                System.Console.WriteLine(granted);
            });

            // For iOS 10 display notification (sent via APNS)
            UNUserNotificationCenter.Current.Delegate = this;

            // For iOS 10 data message (sent via FCM)
            Messaging.SharedInstance.Delegate = this;
        }
        else
        {
            // iOS 9 or before
            var allNotificationTypes = UIUserNotificationType.Alert | UIUserNotificationType.Badge | UIUserNotificationType.Sound;
            var settings = UIUserNotificationSettings.GetSettingsForTypes(allNotificationTypes, null);
            UIApplication.SharedApplication.RegisterUserNotificationSettings(settings);
        }

        UIApplication.SharedApplication.RegisterForRemoteNotifications();

        //configure firebase analytics.
        App.Configure();

        DoFCMConnect();
        return true;
    }

    private void DoFCMConnect()
    {
        Messaging.SharedInstance.ShouldEstablishDirectChannel = true;

        Console.WriteLine("Connected to FCM");

        //removed when updated to newest firebase version
        //Messaging.SharedInstance.Connect(error => {
        //    if (error != null)
        //    {
        //        System.Console.WriteLine(String.Format("Re-Connection to FCM Failed: {0}", error.ToString()));
        //    }
        //    else
        //    {
        //        System.Console.WriteLine("Re-Connected to FCM.");
        //    }
        //});
    }

从WebViewController.cs：

public override void ViewDidLoad()
    {
        string url = "https://www.mydomainname.com"; // NOTE: https secure request is required.

        string token = InstanceId.SharedInstance.Token;
        string fcm = Messaging.SharedInstance.FcmToken;

        if (token == null && fcm != null)
        {
            token = fcm;
        }

        if (String.IsNullOrEmpty(token))
        {
            url += "/login";
        }
        else
        {
            url += "/app-in/{0}"; //page accepts token and associates it to the user after login.
            url = String.Format(url, System.Web.HttpUtility.UrlEncode(token));
        }

        WebView.LoadRequest(new NSUrlRequest(new NSUrl(url)));

    }

---

字符串标记和字符串fcm都包含iOS 9的值，但在iOS 11中都为空。

这是一个已知问题，请参阅

请尝试rsattar提供的步骤

将FirebaseInstanceID降级为2.0.0

将UIApplication.shared.RegisterForRemotonifications放在FinishedLaunching的第一行

卸载/重新安装你的应用程序

---

谢谢你的回复，这确实帮了大忙。我之前曾尝试按照其他帖子的建议进行降级，但失败的是：通过NuGet删除所有Firebase.iOS软件包，然后重新安装依赖性最低的.CloudMessaging 2.0。希望这个小道消息能帮助别人。再次感谢你的回复，科尔。