How to stay on the launch screen until auto-login in Scene Delegate is complete?

Question

I am trying to switch screens after auto-login in my scene delegate and everything works except my launch screen appears for like 10ms and then it goes to my ViewController(inital view controller) and then it switches screens to the screen I want it to switch to. My goal is to have the launch screen appear the entire time while I sign-in in the scene delegate and then switch screens after the sign-in is complete. This is the code i am using

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).


        if let windowScene = scene as? UIWindowScene {
                  let window = UIWindow(windowScene: windowScene)
                  let storyboard = UIStoryboard(name: "Main", bundle: nil)
                  if KeychainWrapper.standard.string(forKey: "email") != nil && KeychainWrapper.standard.string(forKey: "password") != nil {
                        Auth.auth().signIn(withEmail: KeychainWrapper.standard.string(forKey: "email")!, password:  KeychainWrapper.standard.string(forKey: "password")!) { (result, error) in
                               if error == nil {
                                    if Auth.auth().currentUser!.isEmailVerified {
                                       /*getting data*/
                                         window.rootViewController = storyboard.instantiateViewController(identifier: "ViewingScreenController") 
                                          self.window = window
                                          window.makeKeyAndVisible()
                                     }
                                     
                           }
                                              
                        }
                                         
                     }
               }
    

        
      // guard let _ = (scene as? UIWindowScene) else { return }
    }```

Answer 1

You've misunderstood what a launch screen is. It is just a transitional thing presented by the runtime before your app even launches. In many cases it won't be visible at all! And that's good, because it means the app launches quickly. See my answer at https://stackoverflow.com/a/59700102/341994.

So you should not build any functionality around the launch screen; it isn't functional. Your goal should be to get past the launch screen, which means your app launches fast, which is correct. What you present then is up to you; your code is now running.