swift - Black screen on Launch: How to support all versions iOS 10 and 13 above in App and Scene Delegate

Question

My app supports older versions of iOS 10.0 and above. When I try to launch my app in iOS 13, it shows a black window. It does configure initial ViewController and shows labels when I remove the scene delegate. Everything works in iOS 12 and under with just App delegate.

In my App delegate:

@main
class AppDelegate: UIResponder, UIApplicationDelegate {
    
    var window: UIWindow?
    
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        configureInitialViewController()
        return true
    }

    func configureInitialViewController()
    {
        var initialVC: UIViewController
        let mainsb = UIStoryboard(name: "Main", bundle: nil)
        if Auth.auth().currentUser != nil {
            //print("successfully signed in")
            initialVC = mainsb.instantiateViewController(withIdentifier: IDENTIFIER_MAIN_TABBAR)
        } else {
            //print("successfully signed out")
            initialVC = mainsb.instantiateViewController(withIdentifier: IDENTIFIER_WELCOME_NAV)
        }

        window?.rootViewController = initialVC
        window?.makeKeyAndVisible()
    }
    
    func applicationWillResignActive(_ application: UIApplication) {
        Api.User.isOnline(bool: false)
    }

    // 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.
    }
}

In my Scene delegate:

@available(iOS 13.0, *)
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    var window: UIWindow?

    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 _ = (scene as? UIWindowScene) else { return }
    }

    func sceneWillResignActive(_ scene: UIScene) {
        Api.User.isOnline(bool: false)
        
    }
}

I also deleted Application Scene Manifest in my info.plist.

Can someone help me check if I'm setting up version supports correctly?

I would really appreciate any help.

Update:

I tested it works in iOS 13.5 but not 13.2 or 14.3. Why is it showing different behaviors in different versions?

question from:https://stackoverflow.com/questions/66057808/black-screen-on-launch-how-to-support-all-versions-ios-10-and-13-above-in-app-a

Answer 1

In your AppDelegate inside didFinishLaunchingWithOptions add this:

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    // Override point for customization after application launch.
    if #available(iOS 13.0, *){}
    else{
        //Load your vc
    }
    return true
}

Then in your SceneDelegate inside willConnectTo add these:

@available(iOS 13.0, *)
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 _ = (scene as? UIWindowScene) else { return }
    guard let windowScene = (scene as? UIWindowScene) else {return}
    let window:UIWindow = UIWindow(windowScene: windowScene)
    self.window = window
    self.window?.rootViewController = // set you VC
    self.window?.makeKeyAndVisible()
    
}