Xcode 11.3+ SceneDelegate Update 4/20/2020

As most of you are probably aware by now, starting with Xcode 11.3, Single View Application projects are now created with a SceneDelegate file. This file is used to manange the scenes in your application and thus also contains the entry point of your app. Because of this change, we'll need to go about setting up our project using SceneDelegate instead of AppDelegate. More specifically, you want to leave AppDelegate alone and instead make the following changes in SceneDelegate:

class SceneDelegate: UIResponder, UIWindowSceneDelegate {    var window: UIWindow?        func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {        if let windowScene = scene as? UIWindowScene {            let window = UIWindow(windowScene: windowScene)            window.rootViewController = MainTabBarController()            self.window = window window.makeKeyAndVisible()        }    }}