scene-delegates-programmatic-window-creation.swift

    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        
        /// 1. Capture the scene
        guard let windowScene = (scene as? UIWindowScene) else { return }
        
        /// 2. Create a new UIWindow using the windowScene constructor which takes in a window scene.
        let window = UIWindow(windowScene: windowScene)
        
        /// 3. Create a view hierarchy programmatically
        let viewController = ArticleListViewController()
        let navigation = UINavigationController(rootViewController: viewController)
        
        /// 4. Set the root view controller of the window with your view controller
        window.rootViewController = navigation
        
        /// 5. Set the window and call makeKeyAndVisible()
        self.window = window
        window.makeKeyAndVisible()
    }
  

How to programmatically setup your app with Scene Delegate in Swift

Step 1/4: Remove the Main.storyboard file
You’ll want to remove the Main.storyboard file and get rid of the ViewController.swift file as you’ll most likely want to create your own initial view controller. At the very least you can just rename that class to something more relevant to your app.

Step 2/4: Remove 2 key value pairs in info.plist
You’ll then want to go ahead and delete the following key value pairs in your info.plist file:

1. Storyboard Name
2. Main storyboard file base name
   and in AppleScript terminology they’re named UISceneStoryboardFile and UIMainStoryboardFile respectively
   

Step 3/4: Create your initial view controller

Step 4/4: Programmatically create your window hierarchy

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions)

[iOS] AppDelegate와 SceneDelegate

Deployment Target이 iOS 13 미만인 상황에서는?

1. iOS13에서 새로 생긴 SceneDelegate.swift 파일 삭제
2. iOS13에서 AppDelegate에 추가된 UISceneSession과 관련된 두 매소드 삭제

// MARK: UISceneSession Lifecycle

@available(iOS 13.0, *)
func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
    // Called when a new scene session is being created.
    // Use this method to select a configuration to create the new scene with.
    return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
}

@available(iOS 13.0, *)
func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
    // Called when the user discards a scene session.
    // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
    // Use this method to release any resources that were specific to the discarded scenes, as they will not return.
}

3. iOS13에서 SceneDelegate로 옮겨진 window 프로퍼티를 AppDelegate로 다시 옮기기

var window: UIWindow?

4. info.plist에서 Scene과 관련된 Manifest인 Application Scene Manifest 삭제