private static void OnStrokePropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            PolarStrokedAnnotation annotation = sender as PolarStrokedAnnotation;

            annotation.Presenter.Stroke = e.NewValue as Brush;
        }
        private static void OnStrokeThicknessPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            PolarStrokedAnnotation annotation = sender as PolarStrokedAnnotation;

            annotation.Presenter.StrokeThickness = (double)e.NewValue;
        }
        private static void OnStrokeDashArrayChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            PolarStrokedAnnotation annotation = sender as PolarStrokedAnnotation;

            annotation.Presenter.StrokeDashArray = (e.NewValue as DoubleCollection).Clone();
        }