protected override void OnFinalRevoke()
{
if (null != hwndSource)
{
CommandManager.RemoveCanExecuteHandler((UIElement)hwndSource.RootVisual, CanExecuteRoutedEventHandler);
CommandManager.RemoveExecutedHandler((UIElement)hwndSource.RootVisual, ExecuteRoutedEventHandler);
if (!hwndSource.CheckAccess())
{
hwndSource.Dispatcher.Invoke(hwndSource.Dispose);
}
else
{
hwndSource.Dispose();
}
hwndSource = null;
}
if (null != observer)
{
observer.Dispose();
observer = null;
}
base.OnFinalRevoke();
}