static void OnRatingChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
RatingCell cell = (RatingCell)d;
for (int i = 0; i < cell.Children.Count; i++)
{
cell.Children[i].Opacity = i < cell.Rating ? ON : OFF;
}
}
void img_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
// calculate rating based on the index of the star
C1Icon img = sender as C1Icon;
RatingCell cell = img.Parent as RatingCell;
int index = cell.Children.IndexOf(img);
if (index > 0 || e.GetPosition(img).X > img.Width / 3)
{
index++;
}
// apply the new rating
cell.Rating = index;
}