protected override void OnPreviewMouseDown(MouseButtonEventArgs e)
{
base.OnPreviewMouseDown(e);
DesignerCanvas designer = VisualTreeHelper.GetParent(this) as DesignerCanvas;
if (designer != null)
{
if ((Keyboard.Modifiers & (ModifierKeys.Shift | ModifierKeys.Control)) != ModifierKeys.None)
{
this.IsSelected = !this.IsSelected;
}
else
{
if (!this.IsSelected)
{
designer.DeselectAll();
this.IsSelected = true;
}
}
}
e.Handled = false;
}
