因此,我有一个UIPageViewController,其中我想实现spineLocation to be .mid,如果设备在横向,.min用于纵向,因此在横向中显示两个控制器,在纵向中显示一个。orientation: UIInterfaceOrientation) -> UIPageViewController.SpineLocation {
if orientation == .willRotate(to toInterfaceOrientation: UIInterfaceOrientation,持续时间: TimeInterval)