private void ResizeThumb_DragStarted(object sender, DragStartedEventArgs e)
{
parentCanvas = DesignerCanvas.FindDesignerCanvas(this);
var destControl = DataContext as IBoxCanvasItem;
if (parentCanvas != null && destControl != null)
{
var adornerLayer = AdornerLayer.GetAdornerLayer(this);
if (adornerLayer != null)
{
Debug.Assert(sizeAdorner == null);
sizeAdorner = new SizeAdorner(destControl);
parentCanvas.AddAdorner(sizeAdorner);
}
}
}
