Xamarin.iOS 无法创建/打开故事板

Question

我们在 Xamarin.iOS 中创建故事板时遇到问题。 我们已经与 Mac 配对，并且在 VS GUI 上它说它已连接。 当我们尝试创建（或在新项目中打开现有的故事板）时，我们得到同样的错误：

System.AggregateException: One or more errors occurred. ---> System.AggregateException: One or more errors occurred. ---> MonoTouch.Design.Client.InvalidSessionException: Error in the application.
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest(CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\79\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 235
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest[TResponse](CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\79\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 252
   at MonoTouch.Design.Client.ServerProcessConnection.CreateSession() in E:\A\_work\79\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 111
   at MonoTouch.Design.Client.ServerProcessConnection.<CreateSessionAsync>b__28_0() in E:\A\_work\79\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 116
   at System.Threading.Tasks.Task`1.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.VisualStudio.Telemetry.WindowsErrorReporting.WatsonReport.GetClrWatsonExceptionInfo(Exception exceptionObject)
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at System.Threading.Tasks.Task`1.get_Result()
   at MonoTouch.Design.Client.IPhoneDesignerSession.<>c__DisplayClass289_1`1.<EnsureSession>b__1(Task`1 t) in E:\A\_work\79\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\IPhoneDesignerSession.cs:line 2070
   at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at System.Threading.Tasks.Task.Wait()
   at MonoTouch.Design.Client.IPhoneDesignerSession.<>c__DisplayClass289_0`1.<EnsureSession>b__0() in E:\A\_work\79\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\IPhoneDesignerSession.cs:line 2136
   at System.Threading.Tasks.Task`1.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()
--- End of stack trace from previous location where exception was thrown ---
[Truncated here]

Windows 10 和 Catalina 上的 VS 版本都是最新版本（无法再更新），Xcode 版本为 11.3

我在网上阅读了很多文章，说要更新并重新启动 IDE，应该没问题，但是我什么也做不了...

有谁知道如何解决这个问题？

Answer 1

问题似乎是在 macOS 版本中。
我与一些使用不同类型软件（Flash Builder）的同事交谈过，他说他在 Catalina macOS 上也有类似的问题。
所以我切换回Mojave ，更新到 10.4.16 。 并安装了 Xcode 和 VSforMac，它终于可以工作了（或适用于 iPhone 8 iOS 13）