The UISplitViewController class is a container view controller that presents a master-detail interface. In a master-detail interface, changes in the primary view controller (the master) drive changes in a secondary view controller (the detail). The two view controllers can be arranged so that they are side-by-side, so that only one at a time is visible, or so that one only partially hides the other.
The UISplitViewController class is a container view controller that manages the presentation of two side-by-side view controllers. You use this class to implement a Master-Detail interface, in which the left-side view controller presents a list of items and the right-side presents details of the selected item. In iOS 8 and later, you can use the UISplitViewController class on all iOS devices; in previous versions of iOS, the class is available only on iPad.
After creating and initializing an instance of this class, you must assign two view controllers to the viewControllers property. The split view controller has no significant interface of its own because its job is to coordinate the presentation of its two child view controllers and to manage the transitions among different orientations.
A split view controller supports the same interface orientations as its currently visible child view controllers. Both view controllers are displayed in landscape orientations but only the detail view controller is displayed in portrait orientations. When transitioning between orientations, the split view controller sends messages to its delegate object to coordinate the display of a popover with the hidden view controller. For more information on the methods of this delegate object, see UISplitViewControllerDelegate Protocol Reference.
