Metro应用中的键盘快捷键

Question

How do I capture a keyboard shortcut, no matter which control has focus? I don't want to go and write the same thing for each possible control that the user could give focus to. So how can I watch for a page-wide/control-independent shortcut?

Answer 1

Add this code to the constructor it will handle a global key down and key

Window.Current.CoreWindow.KeyDown += CoreWindow_KeyDown;
        Window.Current.CoreWindow.KeyUp += CoreWindow_KeyUp;

heres their events

void CoreWindow_KeyUp(Windows.UI.Core.CoreWindow sender, Windows.UI.Core.KeyEventArgs args)
    {
        //this.Frame.Navigate(typeof(MainPage));
        var key = args.VirtualKey;
        string aa = args.ToString();
    }

    void CoreWindow_KeyDown(Windows.UI.Core.CoreWindow sender, Windows.UI.Core.KeyEventArgs args)
    {
        //this.Frame.Navigate(typeof(MainPage));
        var key = args.VirtualKey;
        string aa = args.ToString();
    }

you can ahndle your own logic inside this event.

Answer 2

How about setting an event handler at the root element? I think event will eventually reach the parent control, if it is not handled anywhere else. Here's what I would do for a simple KeyDown event.

<common:LayoutAwarePage
x:Name="pageRoot"
//elided
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" KeyDown="MyEventHandler">

Answer 3

The best solution was to use the root element as suggested previously, because global shortcuts use the functions of one class applied to every page, meaning that one must handle each shortcut separately on each page or risk errors.

My XAML was set up as follows:

<Page
   Name="root"
    ...>

    ...

</Page>

My C# to manipulate that page is like this:

... 
namespace DenisQuiz.UWP
{
   public sealed partial class StudyADeck : Page
   {
      ...
      public StudyADeck()
      {
         ...
         // Keyboard shortcuts
         root.KeyDown += Root_KeyDown;
      }

      private void Root_KeyDown(object sender, KeyRoutedEventArgs e)
      {
         switch (e.Key)
         {
            case Windows.System.VirtualKey.F:
               FlipCard();
               break;
            case Windows.System.VirtualKey.Right:
               NextCard();
               break;
            case Windows.System.VirtualKey.Left:
               PreviousCard();
               break;
            case Windows.System.VirtualKey.S:
               Frame.GoBack(); // Stop Studying
               break;
            case Windows.System.VirtualKey.E:
               Frame.Navigate(typeof(EditANotecard)); // Edit this card
               break;
            case Windows.System.VirtualKey.D:
               DeleteNotecardAsync();
               break;
            default:
               break;
         }
      }
...

The name root is accessed via any keypress made when that window is open, via the expression root.KeyDown += Root_KeyDown . That calls the Root_KeyDown() method, which then can implement any function based on the key send by the keypress argument KeyRoutedEventArgs e .

My code implements a switch statement to determine key functions.