private static void OnStoryboardChanged(DependencyObject target, DependencyPropertyChangedEventArgs e)
 {
     var oldListener = (StoryboardListener)target.GetValue(StoryboardCompleteBehavior.StoryboardListenerProperty);
     if (oldListener != null)
     {
         oldListener.DeleteHandler();
     }
     Storyboard storyboard = (Storyboard)e.NewValue;
     storyboard.Stop();
     var listener = new StoryboardListener(target, storyboard);
     target.SetValue(StoryboardCompleteBehavior.StoryboardListenerProperty, listener);
 }
        private static void OnStoryboardChanged(DependencyObject target, DependencyPropertyChangedEventArgs e)
        {
            var oldListener = (StoryboardListener)target.GetValue(StoryboardCompleteBehavior.StoryboardListenerProperty);

            if (oldListener != null)
            {
                oldListener.DeleteHandler();
            }
            Storyboard storyboard = (Storyboard)e.NewValue;
            var        listener   = new StoryboardListener(target, storyboard);

            target.SetValue(StoryboardCompleteBehavior.StoryboardListenerProperty, listener);
        }