去除SceneDelegate

• 删除SceneDelegate.swift 文件
• Targets->ProjectName -> Info -> Custom iOS Target Properties -> 删除 Application Scene Manifest
• AppDelegate 里 屏蔽/删除 UISceneSession Lifecycle 的两个方法

func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration

func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) 

去除Main.storyboard

• 删除Main.storyboard 文件
• Targets->ProjectName -> General -> Deployment Info -> Main Infterface -> 把 main删除
• 申明并实例化window

var window: UIWindow?

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    // Override point for customization after application launch.

    window = UIWindow(frame: UIScreen.main.bounds)
    window?.rootViewController = ViewController()
    window?.makeKeyAndVisible()        
    return true
}