Informs the tab view controller that the specified tab is about to be selected.
- macOS 10.10+
The tab view object whose tab is about to be selected.
The tab view item that will be selected.
This method is a delegate method called by the
NSTab object when changes occur. Use it to update your UI or perform any tasks before a tab is selected.
If you override this method, you must call
super at some point in your implementation.