See Also: UITraitCollection Members
This class holds the elements describing the user interface traits to use to render a view or view controller. This contains components like the size class for the vertical or horizontal orientations (which is either compact or regular) as well as the user interface idiom (iPad or iPhone form factor) as well as the display scale.
This is typically used by developers when implementing their own UIKIt.UIViewController as well by a handful of classes that are UITraitCollection aware, like UIKIt.UIImage and UIKIt.UIImageAsset.