A set of methods that, in conjunction with a presentation controller, determine how to respond to trait changes in your app.
After implementing an object that conforms to this protocol, assign that object to the delegate property of an appropriate UIPresentationController object. Your delegate can suggest a new presentation style or an entirely new view controller for displaying content. For more information about using the delegate to respond to size class changes, see UIPresentationController.
A collection of methods that makes the iOS interface environment available to your app.
This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.