如果您使用的是 ios 13 或更高版本，则需要使用 UIWindowSceneDelegate。使用以下方法在SceneDelegate 文件中初始化您的应用，
import UIKit
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 }
if isLogin == false
{
self.window = UIWindow(frame: UIScreen.main.bounds)
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let initialViewController = storyboard.instantiateViewController(withIdentifier: "LoginVC")
self.window?.rootViewController = initialViewController
self.window?.makeKeyAndVisible()
}
else
{
self.window = UIWindow(frame: UIScreen.main.bounds)
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let initialViewController = storyboard.instantiateViewController(withIdentifier: "TabBarVC")
self.window?.rootViewController = initialViewController
self.window?.makeKeyAndVisible()
}
}
}
AppDelegate 文件，
import UIKit
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
if #available(iOS 13.0, *) {
} else {
if isLogin == false
{
self.window = UIWindow(frame: UIScreen.main.bounds)
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let initialViewController = storyboard.instantiateViewController(withIdentifier: "LoginVC")
self.window?.rootViewController = initialViewController
self.window?.makeKeyAndVisible()
}
else
{
self.window = UIWindow(frame: UIScreen.main.bounds)
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let initialViewController = storyboard.instantiateViewController(withIdentifier: "TabBarVC")
self.window?.rootViewController = initialViewController
self.window?.makeKeyAndVisible()
}
}
return true
}
// MARK: UISceneSession Lifecycle
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)
}
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.
}
}
对于ios 13以下，不需要像self.window = UIWindow(frame: UIScreen.main.bounds)那样初始化窗口。只需使用该应用程序自动在AppDelegate 中创建窗口属性。