(UWP) 使用 ESC 键关闭 ModalDialog

Question

我在 Template10 中使用示例代码 Busy.xaml 显示 ModalDialog :

    public static void SetBusy(bool busy, string text = null)
    {
        WindowWrapper.Current().Dispatcher.Dispatch(() =>
        {
            var modal = Window.Current.Content as ModalDialog;
            var view = modal.ModalContent as Busy;
            if (view == null)
                modal.ModalContent = view = new Busy();
            modal.IsModal = view.IsBusy = busy;
            view.BusyText = text;
            modal.CanBackButtonDismiss = true;
        });
    }

我可以使用 ALT+Left Arrow 关闭此对话框，但在大多数桌面应用程序中，按 ESC 键通常也会关闭弹出窗口或对话框。

我尝试添加代码来处理 Busy.xaml 上的 KeyDown 但是当我按下 ESC 或任何键时此方法从未执行。

     private void UserControl_KeyDown(object sender, KeyRoutedEventArgs e)
     {
         if (e.Key == VirtualKey.Escape)
         {
             e.Handled = true;
             SetBusy(false);
         }
     }

那么，如何让这个 ModalDialog 在用户按下 ESC 键时关闭？

Answer 1

当模式打开时，只需沿着这条路线使用一些东西：

private void Modal_KeyDown(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.Escape)
    {
        this.Close();
    }
}

另一种解决 (e.KeyCode==Keys.Escape) 的方法是：

(e.KeyChar == (char)27)

或

e.KeyCode==(char)Keys.Escape

要使此代码生效，您需要 Form.KeyPreview = true;

有关以上内容的更多信息：https://msdn.microsoft.com/en-us/library/system.windows.forms.control.keydown.aspx

我认为您需要附加 CancelButton 属性才能正常工作。

（几乎相同的方法）我相信这应该也能很好地工作：

private void HandleEsc(object sender, KeyEventArgs e)
{
    if (e.Key == Key.Escape)
        Close();
}

这是一个控制台应用程序：

if (Console.ReadKey().Key == ConsoleKey.Escape)
{
    return;
}

Answer 2

您必须将事件处理程序附加到 CoreWindow 的 CharacterReceived 事件。

修改SetBusy方法：

public static void SetBusy(bool busy, string text = null)
{
    WindowWrapper.Current().Dispatcher.Dispatch(() =>
    {
        var modal = Window.Current.Content as ModalDialog;
        var view = modal.ModalContent as Busy;
        if (view == null)
            modal.ModalContent = view = new Busy();
        modal.IsModal = view.IsBusy = busy;
        view.BusyText = text;
        modal.CanBackButtonDismiss = true;

        // Attach to key inputs event
        var coreWindow = Window.Current.CoreWindow;
        coreWindow.CharacterReceived += CoreWindow_CharacterReceived;
    });
}

CoreWindow_CharacterReceived 看起来像这样：

private static void CoreWindow_CharacterReceived(CoreWindow sender,
                                                 CharacterReceivedEventArgs args)
{
    // KeyCode 27 = Escape key
    if (args.KeyCode != 27) return;

    // Detatch from key inputs event
    var coreWindow = Window.Current.CoreWindow;
    coreWindow.CharacterReceived -= CoreWindow_CharacterReceived;

    // TODO: Go back, close window, confirm, etc.
}

(UWP) 使用 ESC 键关闭 ModalDialog

(UWP) Using ESC Key to Close ModalDialog

c#

xaml

uwp

template10