private void ResizeThumb_DragDelta(object sender, DragDeltaEventArgs e) { if (_designerItem != null) { var scaleTransform = _designerItem.GetTransform <ScaleTransform>(); var scaleX = scaleTransform.ScaleX; var scaleY = scaleTransform.ScaleY; var ha = scaleX == -1 ? HorizontalAlignment.Invert() : HorizontalAlignment; var va = scaleY == -1 ? VerticalAlignment.Invert() : VerticalAlignment; Resize(e, va, ha); } e.Handled = true; }