Starting in iOS 8, you should employ the UITraitCollection and UITraitEnvironment APIs, and size class properties as used in those APIs, instead of using UIInterfaceOrientation constants or otherwise writing your app in terms of interface orientation.
In earlier versions of iOS, you used these constants in the statusBarOrientation property and the setStatusBarOrientation(_:animated:) method. Notice that UIDeviceOrientationLandscapeRightis assigned to UIInterfaceOrientationLandscapeLeft and UIDeviceOrientationLandscapeLeft is assigned to UIInterfaceOrientationLandscapeRight; the reason for this is that rotating the device requires rotating the content in the opposite direction.
This exception is thrown if a view controller or the app returns 0 instead of a valid set of supported interface orientation values. It is also thrown if the orientation returned by a view controller’s preferredInterfaceOrientationForPresentation method does not match one of the view controller’s supported orientations.
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.