直接创建HwndSource

我试图通过直接创建HwndSource来创建窗口。目前我有一个替代解决方案 - 继承Window类，但我只是好奇我的HwndSource实现有什么问题。由于Window在其核心使用HwndSource，我觉得应该有一种方法。直接创建HwndSource

这里是我的代码的简化版本：如预期

private void ButtonBase_OnClick(object sender, RoutedEventArgs e) 
{ 
    HwndSource wndPopup = new HwndSource(0, 0x12cf0000/*WS_VISIBLE|WS_OVERLAPPEDWINDOW*/, 0, 10, 10, 500, 500, "Test", IntPtr.Zero); 
    wndPopup.RootVisual = new Rectangle() { Fill = Brushes.Red, Width = 100, Height = 100 }; 
}

窗口创建，但在我关闭它（Alt + F4键或关闭图标）和悬停鼠标在我的主窗口中，大量邮件被吐唾沫到调试：

抛出异常： 'System.ComponentModel.Win32Exception' 在WindowsBase.dll

异常详细信息如下：

Exception thrown: 'System.ComponentModel.Win32Exception' in WindowsBase.dll 
Additional information: Invalid window handle

堆栈跟踪：

WindowsBase.dll!MS.Win32.UnsafeNativeMethods.GetWindowText(System.Runtime.InteropServices.HandleRef, System.Text.StringBuilder, int) 
PresentationCore.dll!System.Windows.Automation.Peers.GenericRootAutomationPeer.GetNameCore() 
PresentationCore.dll!System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() 
PresentationCore.dll!System.Windows.ContextLayoutManager.fireAutomationEvents() 
PresentationCore.dll!System.Windows.ContextLayoutManager.UpdateLayout() 
PresentationCore.dll!System.Windows.ContextLayoutManager.UpdateLayoutCallback(object) 
PresentationCore.dll!System.Windows.Media.MediaContext.InvokeOnRenderCallback.DoWork() 
PresentationCore.dll!System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks() 
PresentationCore.dll!System.Windows.Media.MediaContext.RenderMessageHandlerCore(object) 
PresentationCore.dll!System.Windows.Media.MediaContext.RenderMessageHandler(object) 
WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate, object, int) 
WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.TryCatchWhen(object, System.Delegate, object, int, System.Delegate) 
WindowsBase.dll!System.Windows.Threading.DispatcherOperation.InvokeImpl() 
WindowsBase.dll!System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(object) 
mscorlib.dll!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, object, bool) 
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, object, bool) 
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, object) 
WindowsBase.dll!System.Windows.Threading.DispatcherOperation.Invoke() 
WindowsBase.dll!System.Windows.Threading.Dispatcher.ProcessQueue() 
WindowsBase.dll!System.Windows.Threading.Dispatcher.WndProcHook(System.IntPtr, int, System.IntPtr, System.IntPtr, ref bool) 
WindowsBase.dll!MS.Win32.HwndWrapper.WndProc(System.IntPtr, int, System.IntPtr, System.IntPtr, ref bool) 
WindowsBase.dll!MS.Win32.HwndSubclass.DispatcherCallbackOperation(object) 
WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate, object, int) 
WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.TryCatchWhen(object, System.Delegate, object, int, System.Delegate) 
WindowsBase.dll!System.Windows.Threading.Dispatcher.LegacyInvokeImpl(System.Windows.Threading.DispatcherPriority, System.TimeSpan, System.Delegate, object, int) 
WindowsBase.dll!MS.Win32.HwndSubclass.SubclassWndProc(System.IntPtr, int, System.IntPtr, System.IntPtr) 
[Native to Managed Transition]  
[Managed to Native Transition]  
WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrameImpl(System.Windows.Threading.DispatcherFrame) 
WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrame(System.Windows.Threading.DispatcherFrame) 
PresentationFramework.dll!System.Windows.Application.RunDispatcher(object) 
PresentationFramework.dll!System.Windows.Application.RunInternal(System.Windows.Window) 
PresentationFramework.dll!System.Windows.Application.Run(System.Windows.Window) 
PresentationFramework.dll!System.Windows.Application.Run() 
WpfCombox.exe!WpfCombox.App.Main() 
[Native to Managed Transition]  
[Managed to Native Transition]  
mscorlib.dll!System.AppDomain.ExecuteAssembly(string, System.Security.Policy.Evidence, string[]) 
Microsoft.VisualStudio.HostingProcess.Utilities.dll!Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly() 
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart_Context(object) 
mscorlib.dll!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, object, bool) 
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, object, bool) 
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, object) 
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart()

因此，错误发生深刻的某处框架代码。

我试图填充其他属性或将清理添加到Disposed处理程序，但对结果没有影响。如果我没有设置RootVisual，那就没有错误（但是，当然，这不是一个选项）。

任何想法我失踪？

来源

2017-05-11 nevermind

不能重复。我的窗户似乎表现良好。关闭后我没有看到任何例外。 – AQuirky

@AQuirky为了澄清：这不是一个未处理的异常。消息被写入输出窗口，程序继续。但是1）它表明有什么错误2）由于很多这样的消息被添加到输出，调试变得非常慢 – nevermind

是的，我明白了。我的调试器输出窗口中没有任何内容。 – AQuirky

我发现的一个解决方案是为根视觉创建一个自动化对等体。否则，GenericRootAutomationPeer将由框架创建，该框架调用GetWindowText Windows API。

public class PopupRootAutomationPeer : UIElementAutomationPeer 
{ 
    public PopupRootAutomationPeer(FrameworkElement owner) 
     : base(owner) { } 

    protected override string GetClassNameCore() 
    { 
     return "Pane"; 
    } 

    protected override AutomationControlType GetAutomationControlTypeCore() 
    { 
     return AutomationControlType.Pane; 
    } 

    protected override string GetNameCore() 
    { 
     return "PopupRootAutomationPeer"; 
    } 
} 

// Wrap content of the window with this class 
class PopupRoot : Canvas 
{ 
    protected override AutomationPeer OnCreateAutomationPeer() 
    { 
     return new PopupRootAutomationPeer(this); 
    } 
}

有可能是要取消初始化的HwndSource当它关闭，使自动化不叫上不存在窗口的方式，但我还没有找到它。

来源

2017-05-11 18:17:32 nevermind

直接创建HwndSource

回答

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