Notifies the view immediately before it moves to a new window (which may be
- macOS 10.10+
The window object that will be at the root of the view's new view hierarchy. If the view is being removed from a window and there isn't a new window, this parameter is
When subclassing, you can override this method and use it to perform any tasks associated with the change. You must call
super at some point during your implementation.