Just for reference, the CommandReference class is currently not included in an assembly that you can reference, but is included with the M-V-VM project template. So if you don't build your application from the template, then you have to get the class from somewhere else. I chose to copy it from the sample project. I included it below to allow everyone easy access to this little chunk of goodness, but be sure to check for updates to the template in future versions of the M-V-VM Toolkit.
/// <summary>
/// This class facilitates associating a key binding in XAML markup to a command
/// defined in a View Model by exposing a Command dependency property.
/// The class derives from Freezable to work around a limitation in WPF when data-binding from XAML.
/// </summary>
public class CommandReference : Freezable, ICommand
{
public CommandReference( )
{
}
public static readonly DependencyProperty CommandProperty = DependencyProperty.Register( "Command", typeof( ICommand ), typeof( CommandReference ), new PropertyMetadata( new PropertyChangedCallback( OnCommandChanged ) ) );
public ICommand Command
{
get { return (ICommand)GetValue( CommandProperty ); }
set { SetValue( CommandProperty, value ); }
}
#region ICommand Members
public bool CanExecute(object parameter)
{
if (Command != null)
return Command.CanExecute( parameter );
return false;
}
public void Execute(object parameter)
{
Command.Execute( parameter );
}
public event EventHandler CanExecuteChanged;
private static void OnCommandChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
CommandReference commandReference = d as CommandReference;
if (commandReference != null)
{
ICommand oldCommand = e.OldValue as ICommand;
if (oldCommand != null)
oldCommand.CanExecuteChanged -= commandReference.CanExecuteChanged;
ICommand newCommand = e.NewValue as ICommand;
if (newCommand != null)
newCommand.CanExecuteChanged += commandReference.CanExecuteChanged;
}
}
#endregion
#region Freezable
protected override Freezable CreateInstanceCore( )
{
return new CommandReference();
}
#endregion
}
Enjoy!
