protected override void OnInitialized(EventArgs e) { if (TemplatedParent == null) { throw new InvalidOperationException("Must be in a template"); } base.OnInitialized(e); if (AdornedElement != null) { BindingOperations.SetBinding(this, WidthProperty, AdornedElement.CreateOneWayBinding(ActualWidthProperty)); BindingOperations.SetBinding(this, HeightProperty, AdornedElement.CreateOneWayBinding(ActualHeightProperty)); } }