private void StartStoryboard(StackPanel PART_StackPanel)
{
Storyboard storyBoard = new Storyboard();
ThicknessAnimation animation = new ThicknessAnimation();
animation.From = new Thickness(-30, 0, 0, 0);
animation.To = new Thickness(-10, 0, 0, 0);
animation.Duration = new Duration(new TimeSpan(1000));
storyBoard.Children.Add(animation);
storyBoard.RepeatBehavior = RepeatBehavior.Forever;
Storyboard.SetTargetName(animation, PART_StackPanel.Name);
Storyboard.SetTargetProperty(animation, new PropertyPath(StackPanel.MarginProperty));
PART_StackPanel.BeginStoryboard(storyBoard);
}