Using a Tab View Delegate

NSTabView defines delegate messages to allow the delegate to control or react to changes in selection and changes in the number of tabs:

• tabViewDidChangeNumberOfTabViewItems: informs the delegate that the number of tab view items in the tab view has changed.

• tabView:didSelectTabViewItem: informs the delegate that the specified tab view item has been selected.

• tabView:shouldSelectTabViewItem: informs the delegate that the specified tab view item is about to be selected. The delegate can return NO to prevent the selection.

• tabView:willSelectTabViewItem: informs the delegate that the specified tab view item will be selected. The delegate can perform tasks related to the selection, but cannot prevent it.