Creating DependencyProperties for a Class

The following code is needed if you want to animate Padding.Top of a control.

public class MyClass : UserControl
{
  public static readonly DependencyProperty PaddingTopProperty =   DependencyProperty.Register("PaddingTop", typeof(double), typeof(MyClass), new PropertyMetadata(0d, new PropertyChangedCallback(OnPaddingTopPropertyChanged)));

  public double PaddingTop
  {
    get
    {
      return Padding.Top;
    }
    set
    {
      Padding = new Thickness(Padding.Left, value, Padding.Right, Padding.Bottom);
    }
  }

  private static void OnPaddingTopPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
  {
    (d as MyClass).PaddingTop = (double)e.NewValue;
  }
}