iOS 13: Swift - 'Set application root view controller programmatically' does not work

Question

I have following code in my AppDelegate.swift to setup root view controller for an iOS application. But it does not work. It follows Target structure (defined under General

Answer 1

I tried following two options and both of these working for me. With iOS-13 (Xcode 11) a new file SceneDelegate.swift with the concept of UIWindowScene is enabled by default.

class SceneDelegate: UIResponder, UIWindowSceneDelegate {

    var window: UIWindow?


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

        guard let windowScene = (scene as? UIWindowScene) else { return }


        self.window = UIWindow(windowScene: windowScene)
        //self.window =  UIWindow(frame: UIScreen.main.bounds)

        let storyboard = UIStoryboard(name: "MyStoryboardName", bundle: nil)
        guard let rootVC = storyboard?.instantiateViewController(identifier: "ViewControllerIdentifierName") as? ViewController else {
            print("ViewController not found")
            return
        }
        let rootNC = UINavigationController(rootViewController: rootVC)
        self.window?.rootViewController = rootNC
        self.window?.makeKeyAndVisible()
    }
}

Alternate:

class SceneDelegate: UIResponder, UIWindowSceneDelegate {

    var window: UIWindow?


    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        let windowScene = UIWindowScene(session: session, connectionOptions: connectionOptions)
        self.window = UIWindow(windowScene: windowScene)
        //self.window =  UIWindow(frame: UIScreen.main.bounds)
        let storyboard = UIStoryboard(name: "MyStoryboardName", bundle: nil)
        guard let rootVC = storyboard?.instantiateViewController(identifier: "ViewControllerIdentifierName") as? ViewController else {
            print("ViewController not found")
            return
        }
        let rootNC = UINavigationController(rootViewController: rootVC)
        self.window?.rootViewController = rootNC
        self.window?.makeKeyAndVisible()

    }
}

I don't know, why and how it works but it resolved my problem.

Reference docs that helped me:

• init(windowScene:)
• UIWindow
• rootViewController