/// <summary>
/// Called when the value of the RatioProperty property changes.
/// </summary>
/// <param name="d">PieDataPoint that changed its Ratio.</param>
/// <param name="e">Event arguments.</param>
private static void OnRatioPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
PieDataPoint source = (PieDataPoint)d;
double oldValue = (double)e.OldValue;
double newValue = (double)e.NewValue;
source.OnRatioPropertyChanged(oldValue, newValue);
}
