ios - 在应用程序超时中显示用户名空白

Question

即使我在 NSUSERdefault 中设置值，我也得到空白用户。它在锁定模式下工作，但相同的代码不适用于应用程序超时(5 分钟)用户是 vcLogin.usernameTxt？.text = uname 为空白甚至 NSUserDefaults.standardUserDefaults().objectForKey("Username") 作为!字符串有值(value)

            let storyboard = UIStoryboard(name: "Main", bundle: nil)
            let vcLogin = storyboard.instantiateViewControllerWithIdentifier("Login") as! LoginViewController
            var uname:String!
            if (NSUserDefaults.standardUserDefaults().objectForKey("Username") != nil) {
                print("username =\(NSUserDefaults.standardUserDefaults().objectForKey("Username"))")
               uname = NSUserDefaults.standardUserDefaults().objectForKey("Username") as! String
                NSUserDefaults.standardUserDefaults().synchronize()

            }else{
              uname = ""
            }



            let navVC = self.window?.rootViewController as? UINavigationController

            var arr=[UIViewController]()
            arr = (navVC?.viewControllers)!


            if ((arr.last?.isKindOfClass(LoginViewController)) != nil) {

               arr.append(vcLogin)
                navVC?.viewControllers = arr
                print("name=\(uname)")
                //if uname != nil {
                vcLogin.usernameTxt?.text =  uname
                //}
            }






        }

    }

Answer 1

let theUsername = NSUserDefaults.standardUserDefaults().objectForKey("Username")!
print("username =\(theUsername)")

顺便问一下，你为什么使用 Swift 2？