如何在iOS上旋转自定义初始屏幕？

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    // 创建自定义的初始屏幕视图控制器
    let initialViewController = CustomInitialViewController()
    
    // 创建一个导航控制器，并将初始屏幕视图控制器设置为根视图控制器
    let navigationController = UINavigationController(rootViewController: initialViewController)
    
    // 设置导航控制器为应用程序的根视图控制器
    window?.rootViewController = navigationController
    window?.makeKeyAndVisible()
    
    return true
}

override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
    return [.portrait, .landscape]
}