A set of methods that define the focus behavior for a branch of the view hierarchy.
- iOS 9.0+
- tvOS 9.0+
UIFocus protocol provides a common interface for specifying and reacting to focus behavior throughout your app. Classes in UIKit that conform to this protocol include
UIPresentation; in other words, classes that are either directly or indirectly in control of views on the screen. Third-party classes should not conform to the