將新的內容頁面添加到Visual Studio 2017中的Xamarin.Forms應用程序時出錯

Question

當我嘗試添加Content Page Visual Studio拋出System.Exception錯誤，然后彈出此消息框：

這是診斷日志文件的內容：

10/02/2018 10:32:33 Recoverable
Microsoft.Assumes+InternalErrorException: Did not find new element in the hierarchy for item "Page1.xaml". The item would have been added with type "Page". The project item schema service knows about this item type. The item does exist in the project file.
   at Microsoft.Assumes.Fail(String message, Boolean showAssert)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.Automation.OAProjectItems.<EvaluateAddResultAsync>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.Automation.OAProjectItems.<>c__DisplayClass1_0.<<AddFromTemplate>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.Automation.OAProject.<>c__DisplayClass68_0`1.<<Mutate>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.<>c__DisplayClass550_0.<<Mutate>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.Threading.JoinableTask.CompleteOnCurrentThread()
   at Microsoft.VisualStudio.ProjectSystem.ProjectMultiThreadedService.ExecuteSynchronously(Func`1 asyncAction)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.Mutate(Func`1 asyncAction, Boolean includesFileSystemChange, String telemetryActivity)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.Automation.OAProject.Mutate[T](Func`1 asyncAction, Boolean includesFileSystemChange, String telemetryActivity)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.Automation.OAProjectItems.AddFromTemplate(String fileName, String name)
   at Microsoft.VisualStudio.TemplateWizard.Wizard.EnumContentsAddItem(ProjectItems projectItems, XmlNode contentNode, String projectName, String currentFolder, String currentTargetFolder, String rootName, String templateFolderPath, String destinationRootFolderPath, String userSpecifiedDestItemPath, String projectTypeString, List`1 wizardExtensions, String rootExtension)
   at Microsoft.VisualStudio.TemplateWizard.Wizard.Execute(Object application, Int32 hwndOwner, Object[]& ContextParams, Object[]& CustomParams, wizardResult& retval)
   at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo)
   at Microsoft.VisualStudio.ErrorHandler.ThrowOnFailure(Int32 hr, Int32[] expectedHRFailure)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.RunWizard(SimpleHierarchyNode parentNode, String itemName, String wizardToRun, IntPtr dlgOwner)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.<AddItemWithSpecificAsync>d__592.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.<>c__DisplayClass457_0.<<AddItem>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.Threading.JoinableTask.CompleteOnCurrentThread()
   at Microsoft.VisualStudio.Threading.JoinableTask`1.CompleteOnCurrentThread()
   at Microsoft.VisualStudio.ProjectSystem.ProjectMultiThreadedService.ExecuteSynchronously[T](Func`1 asyncAction)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.<>c__DisplayClass549_0.<HrInvoke>b__0()
   at Microsoft.VisualStudio.ProjectSystem.VS.HResult.Invoke(Func`1 action, IServiceProvider vsShellServiceProvider, IProjectFaultHandlerService projectFaultHandlerService, UnconfiguredProject project)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.VisualStudio.ProjectSystem.CommonProjectSystemTools.Rethrow(Exception ex)
   at Microsoft.VisualStudio.ProjectSystem.ProjectErrorReporting.<>c__DisplayClass6_0.<SubmitErrorReport>b__0()
   at Microsoft.VisualStudio.ProjectSystem.ExceptionFilter.<>c__DisplayClass2_0.<Guard>b__0()
   at GuardMethodClass.GuardMethod(Func`1 , Func`2 , Func`2 )

重新格式化PC后，我剛剛安裝了Xamarin和Visual Studio，以前從未遇到過此問題。 有人可以幫我解決這個問題嗎？

編輯：

最初，我認為問題是由我安裝的另一個應用程序引起的。 我卸載了IntelliJ和Android Studio（由JetBrains開發），現在可以添加“ Content Page ，但僅將xaml.cs文件添加到項目中。 但是，當我簽入文件資源管理器時， xaml文件位於同一文件夾中，但不在項目中。

我仍然可以編輯xaml文件，但出現錯誤：

名稱“ InitializeComponent”在當前上下文中不存在。

這是xaml文件的內容：

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="App1.Views.Page1">
    <ContentPage.Content>
        <StackLayout>
            <Label Text="Welcome to Xamarin.Forms!\nThis is page 2!!!"
                VerticalOptions="CenterAndExpand" 
                HorizontalOptions="CenterAndExpand" />
        </StackLayout>
    </ContentPage.Content>
</ContentPage>

這是xaml.cs文件的內容：

using Xamarin.Forms;
using Xamarin.Forms.Xaml;

namespace App1.Views
{
    [XamlCompilation(XamlCompilationOptions.Compile)] // <-- I don't remember this being here before. 
    public partial class Page1 : ContentPage
    {
        public Page1 ()
        {
            InitializeComponent ();
        }
    }
}

Answer 1

令人煩惱的是，似乎只需重新安裝Visual Studio即可解決此問題。 現在，我可以添加Content Page沒有任何問題。

更新：

此問題是已報告給Xamarin的錯誤。 解決此問題的最佳方法是與Xamarin一起安裝UWP工作負載，這樣可以消除錯誤。