DemoApp/AppDelegate.swift
import UIKit
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication,
didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
window = UIWindow(frame: UIScreen.main.bounds)
let navigationController = UINavigationController(rootViewController: ViewController())
let tabBarController = UITabBarController(nibName: nil, bundle: nil)
tabBarController.viewControllers = [navigationController]
window?.rootViewController = tabBarController
window?.makeKeyAndVisible()
return true
}
}