import UIKit @UIApplicationMain final class AppDelegate: UIResponder, UIApplicationDelegate { var window: UIWindow? func application( _ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool { let window = UIWindow(frame: UIScreen.main.bounds) window.rootViewController = ViewController() window.makeKeyAndVisible() self.window = window NSLog("Finished launching!") return true } }