Binding a WPF ShortCut Key to a Command in the ViewModel

Question

I have a WPF app that is using the MVVM pattern. Hooking up buttons to the VM is pretty straight forward since they implement the ICommand. I have a context menu that works similar. The next step is to create shortcut keys for the context menu. I can't figure out how to get the shortcut key invoke the Command. Here is an example:

<MenuItem Header="Update" Command="{Binding btnUpdate}" >
    <MenuItem.Icon>
        <Image Source="/Images/Update.png"
               Width="16"
               Height="16" />
        </MenuItem.Icon>
    </MenuItem>

now I've added this:

<Window.InputBindings>
    <KeyBinding Key="U"
                Modifiers="Control" 
                Command="{Binding btnUpdate}" />
</Window.InputBindings>

to try and connect the shortcut keys to the same binding, but this doesn't work. The error is:

Error 169 A 'Binding' cannot be set on the 'Command' property of type 'KeyBinding'. A 'Binding' can only be set on a DependencyProperty of a DependencyObject.

Isn't there a way to hook up this event to the Command? I can't figure this out.

thanks in advance!

Bill

Answer 1

The following code can be used to bind a shortcut key directly to a command:

<Window.InputBindings>
    <KeyBinding Command="{Binding Path=NameOfYourCommand}" 
                Key="O" 
                Modifiers="Control"/>
</Window.InputBindings>

Add this after Window.Resources in the XAML code of your view.