/// <summary> /// Handles notifications when the dragging of the thumb starts. /// </summary> /// <param name="sender">the sender object</param> /// <param name="e">the event arguments</param> private void ResizeThumbDragStarted(object sender, DragStartedEventArgs e) { _designerItem = DataContext as DesignerItem; if (_designerItem == null) { return; } _designerItem.IsResizing = true; _designerItem.IsDragging = true; _designerItems = _designerItem.GetItemsControl(); _transformOrigin = _designerItem.RenderTransformOrigin; var rotateTransform = _designerItem.RenderTransform as RotateTransform; if (rotateTransform != null) { _angle = rotateTransform.Angle * Math.PI / 180.0; } else { _angle = 0.0; } }