private static void SelectedColorPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ColorPicker p = d as ColorPicker;

            if (p != null && p.SelectedColorChanged != null)
            {
                SelectedColorEventArgs args = new SelectedColorEventArgs((Color)e.NewValue);
                p.SelectedColorChanged(p, args);
            }
        }