Question

我的代码以前工作正常，但由于某种原因今天运行它，它执行了不同的任务。我基本上试图在用户使用短用户名，电子邮件或密码时显示警告，否则将发出注册完成的警报，然后转到下一个视图。但是现在，只要我点击提交，它就会转到忽略警报的下一个视图。这是代码：

@IBAction func signUp(_ sender: Any) {        
    // Validate the text fields
    if username!.count < 5 {
        let alert = UIAlertController(title: "Invalid", message: "Username must be greater than 5 characters", preferredStyle: UIAlertControllerStyle.alert)
        let action = UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: nil)
        alert.addAction(action)
        present(alert, animated: true, completion: nil)


    } else if password!.count < 8 {
        let alert = UIAlertController(title: "Invalid", message: "Password must be greater than 7 characters", preferredStyle: UIAlertControllerStyle.alert)
        let action = UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: nil)
        alert.addAction(action)
        present(alert, animated: true, completion: nil)

    } else if email!.count < 8 {
        let alert = UIAlertController(title: "Invalid", message: "Email must be greater than 7 characters", preferredStyle: UIAlertControllerStyle.alert)
        let action = UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: nil)
        alert.addAction(action)
        present(alert, animated: true, completion: nil)

    } else {
        let alert = UIAlertController(title: "Success", message: "Account has been created, an email will be sent shortly", preferredStyle: UIAlertControllerStyle.alert)
        let action = UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: {
            action in
            self.performSegue(withIdentifier: "signUpDone", sender: self)
        })
        alert.addAction(action)
        present(alert, animated: true, completion: nil)
        }
    }

正如你所看到的，我有一个segue＆＃34; signUpDone＆＃34;在句柄中告诉它只进入下一个完整视图。但由于某种原因，它忽略了所有if语句，只是在没有条件或成功警报的单一警报的情况下进入下一个视图。我得到一个控制台信息，上面写着＆＃34;警告：尝试显示其视图不在窗口层次结构中！＆＃34;

我还没有碰过这些代码，但奇怪的是，当我今天尝试运行它时会发生这种情况。可能是什么问题呢？

Answer 1

原来，segue直接从按钮连接到视图而不是视图，这迫使按钮立即转到视图而忽略if语句！

UIAlert突然停止了工作？

1 个答案: