gaeng2y

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
  // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
  // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
  // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
  guard let windowScene = (scene as? UIWindowScene) else { return }
  window = UIWindow(frame: windowScene.coordinateSpace.bounds)
  window?.windowScene = windowScene
  window?.rootViewController = ViewController()
  window?.makeKeyAndVisible()
}

gaeng2y

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
  // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
  // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
  // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
  guard let windowScene = (scene as? UIWindowScene) else { return }
  // 이전 글에서 추가했던 내용
  window = UIWindow(frame: windowScene.coordinateSpace.bounds)
  window?.windowScene = windowScene
  window?.rootViewController = ViewController()
  window?.makeKeyAndVisible()

gaeng2y

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        
        view.backgroundColor = .red
    }
}

gaeng2y

class ViewController: UITabBarController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        
        self.view.backgroundColor = .red
    }
}

gaeng2y

class ViewController: UITabBarController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        
        self.view.backgroundColor = .white
        self.tabBar.tintColor = .systemPink
        self.tabBar.backgroundColor = .systemGray5
        addVC()

gaeng2y

func f(_ nums: [Int]) -> Int {
  sleep(1)
  let sum = nums.reduce(0, +)
  return sum
}

gaeng2y

func af(_ nums: [Int], _ result: @escaping (Int) -> Void) {
  DispatchQueue.main.async {
      sleep(1)
      let sum = nums.reduce(0, +)
      result(sum)
  }
}

gaeng2y

var num = 1

func add(a: Int) -> Int {
  return a + num
}

gaeng2y

func add(a: Int, b: Int) -> Int {
  return a + b
}

let result = add(2, 3) // 5

gaeng2y

 override func viewDidAppear(_ animated: Bool) {
 	super.viewDidAppear(animated)
 
 	setupUI()
 	connectUIControls()
  	createDataSource()
 	listenForChanges()
 }