multi key gesture in wpf

Question

I have a RoutedUICommand called Comment Selection. I need to add an input gesture for this command as it is in VIsual Studio, ie. (Ctrl+K, Ctrl+C). How can I do this? Plz help me. (Keep VS functionality in mind).

Regards, Jawahar

Answer 1

This code is made for "Ctrl+W, Ctrl+E" and/or "Ctrl+W, E" combinations, however you can parametrize it for any key combinations:

XAML:

<MenuItem Header="Header" InputGestureText="Ctrl+W, E" Command="ShowCommand"/>

C#:

public static readonly RoutedUICommand ShowCommand = new RoutedUICommand(
    "Show command text", 
    "Show command desc", 
    typeof(ThisWindow), 
    new InputGestureCollection(new[] { new ShowCommandGesture (Key.E) }));

public class ShowCommandGesture : InputGesture
{
    private readonly Key _key;
    private bool _gotFirstGesture;
    private readonly InputGesture _ctrlWGesture = new KeyGesture(Key.W, ModifierKeys.Control);

    public ShowCommandGesture(Key key)
    {
        _key = key;
    }

    public override bool Matches(object obj, InputEventArgs inputEventArgs)
    {
        KeyEventArgs keyArgs = inputEventArgs as KeyEventArgs;
        if (keyArgs == null || keyArgs.IsRepeat)
            return false;

        if (_gotFirstGesture)
        {
            _gotFirstGesture = false;

            if (keyArgs.Key == _key)
            {
                inputEventArgs.Handled = true;
            }

            return keyArgs.Key == _key;
        }
        else
        {
            _gotFirstGesture = _ctrlWGesture.Matches(null, inputEventArgs);
            if (_gotFirstGesture)
            {
                inputEventArgs.Handled = true;
            }

            return false;
        }
    }
}

Answer 2

I've found this blog post which I think could be of help

http://kent-boogaart.com/blog/multikeygesture

Basically, WPF has no built in support for it, but subclassing InputGesture or KeyGesture seems like a possible way to achieve this without too much hassle.