Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Page-global keyboard events in Windows Store Apps

I'm working on a game, a Windows Store App based on WPF and written in C#. When the player presses the Esc key, I want to pause the game and show a menu (Continue, Quit etc.).

Sounds simple. Sadly, it's not.

The game takes place in a Windows.UI.Xaml.Controls.Page and primarily consists of hundreds of Shapes in a Canvas, but no single Button, TextBox or anything else that supports keyboard interaction. The only interaction is clicking or tapping shapes.

I need to catch keyboard events, globally for the whole page, no matter what element has the focus or if there even is any focus at all etc. Whenever the Esc key is pressed, an event has to fire.

What I tried:

  • Using the event Page.KeyDown or overriding Page.OnKeyDown(KeyRoutedEventArgs e) (or KeyUp): Does not fire, unless there is an element such as a TextBox with keyboard focus. But in my UI there is no such element.

  • Using an invisible (Opacity = 0 and/or hidden under the Canvas) TextBox as a hack to make KeyDown work: As soon as the Canvas or any Shape is clicked/tapped, the TextBox loses focus and the hack stops working. So, more hacks are needed to make it keep the focus, which screws with other things such as the menu buttons. Futhermore, the TextBox occasionally shows the Windows software keyboard, which is rather unwanted. A barely working, fragile hack.

  • Using InputGestures, KeyBinding etc.: Not available for Windows Store Apps.

Any ideas or solutions?

like image 431
Sebastian Negraszus Avatar asked Apr 03 '13 16:04

Sebastian Negraszus


People also ask

How do I add an event to my keyboard?

To record a keypress event in JavaScript, use the code below: // Add event listener on keypress document. addEventListener('keypress', (event) => { var name = event. key; var code = event.

What are the events associated with keyboard?

There are three types of keyboard events: keydown , keypress , and keyup .

Which event is triggered when you click any key on the keyboard?

The keydown event is fired when a key is pressed. Unlike the keypress event, the keydown event is fired for all keys, regardless of whether they produce a character value.


1 Answers

Try using CoreWindow.KeyDown. Assign the handler in your page and I believe it should intercept all keydown events.

public MyPage()
{
    CoreWindow.GetForCurrentThread().KeyDown += MyPage_KeyDown;
}

void MyPage_KeyDown(CoreWindow sender, KeyEventArgs args)
{
    Debug.WriteLine(args.VirtualKey.ToString());
}
like image 114
keyboardP Avatar answered Sep 22 '22 11:09

keyboardP