iOS：加载时的设备方向

Swift
import UIKit
class ViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        NotificationCenter.default.addObserver(self, selector: #selector(orientationDidChange), name: UIDevice.orientationDidChangeNotification, object: nil)
        
        let currentOrientation = UIDevice.current.orientation
        handleOrientationChange(orientation: currentOrientation)
    }
    
    @objc func orientationDidChange() {
        let currentOrientation = UIDevice.current.orientation
        handleOrientationChange(orientation: currentOrientation)
    }
    
    func handleOrientationChange(orientation: UIDeviceOrientation) {
        switch orientation {
        case .portrAIt:
            // 竖屏布局和功能
            break
        case .portrAItUpsideDown:
            // 竖屏布局和功能，Home键在上方
            break
        case .landscapeLeft:
            // 横屏布局和功能，Home键在右侧
            break
        case .landscapeRight:
            // 横屏布局和功能，Home键在左侧
            break
        default:
            // 其他情况
            break
        }
    }
    
}