Returns a view controller the page controller uses for managing the specified identifier.
- macOS 10.8+
The page controller.
The identifier for a view controller.
Returns the view controller for the specified identifier.
Your implementation of this method should return the requested view controller for the identifier or create and return a new view controller.
NSPage will cache as many view controllers and views as necessary to maintain performance. This method is called whenever another instance is required.
The view controller may become the
selected after a transition if necessary.