错误：预期返回“UIViewController”的闭包中缺少返回（Xcode、Swift、iOS 13）答案

【问题标题】：Error: Missing return in a closure expected to return 'UIViewController' (Xcode, Swift, iOS 13)错误：预期返回“UIViewController”的闭包中缺少返回（Xcode、Swift、iOS 13）
【发布时间】：2019-12-27 03:52:13
【问题描述】：

我收到错误消息：“在预期返回 'UIViewController' 的闭包中缺少返回”，在粗体线上。我怎样才能解决这个问题？谢谢！！

   Var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    FirebaseApp.configure()


let hasSession = UserDefaults.standard.value(forKey: "UserHasSubmittedPassword") as? Bool
     let vc: UIViewController = {
               if let hasSession = hasSession, hasSession == true {
                    // next vc you want to show
                } else {
                    // enter password vc
                }
      **}()**

      let navigationController = UINavigationController(rootViewController: vc)
      window?.rootViewController = navigationController
      window?.makeKeyAndVisible()
      return true


    }

【问题讨论】：

标签： swift xcode ios13 swift5 swift5.1

【解决方案1】：

你只需要在闭包中返回 ViewController

Var window: UIWindow?

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    FirebaseApp.configure()

let Myvc = UIViewController()

let hasSession = UserDefaults.standard.value(forKey: "UserHasSubmittedPassword") as? Bool
     let vc: UIViewController = {
               if let hasSession = hasSession, hasSession == true {
                    // next vc you want to show
                       return Myvc
                } else {
                    // enter password vc
                        return Myvc
                }
      **}()**

      let navigationController = UINavigationController(rootViewController: vc)
      window?.rootViewController = navigationController
      window?.makeKeyAndVisible()
      return true
    }

【讨论】：