public void ShouldSetPosition()
        {
            var element = new Placeholder();
            var canvas = new Canvas();
            canvas.Children.Add(element);

            canvas.GetChildPosition(element).ShouldBe(new Point(0,0));

            canvas.SetPosition(element, 10, 5);
            canvas.GetChildPosition(element).ShouldBe(new Point(10, 5));

            canvas.SetPosition(element, new Point(20, 40));
            canvas.GetChildPosition(element).ShouldBe(new Point(20, 40));
        }
        public void Initialize(Canvas control)
        {
            element = new Placeholder();
            dragBehavior = new Draggable();
            sliderBehavior = new PositionSlider{Duration = 1};

            control.Width = 500;
            control.Height = 500;
            control.Background = StyleResources.Colors["Brush.Black.005"] as Brush;
            control.Children.Add(element);

            control.SetPosition(element, 50, 50);

            Behaviors.SetDraggable(element, dragBehavior);
            Behaviors.SetPositionSlider(element, sliderBehavior);

            sliderBehavior.SlideStarted += delegate { Debug.WriteLine("!! SlideStarted"); };
            sliderBehavior.SlideComplete += delegate { Debug.WriteLine("!! SlideComplete"); };
        }