Swift-Firebase身份验证登录功能在演示segue内，如何使用shouldPerformSegue阻止segue执行？

我想使用故事板segue（modally呈现）呈现新的视图控制器，但shouldPerform函数中的验证是Firebase授权函数signIn，但由于尾部闭包直接返回编译器，因此在signIn函数对标志进行任何更改之前，它会返回false

var shouldPerformSegue = false
override func shouldPerformSegue(withIdentifier identifier: String, sender: Any?) -> Bool {
    guard let email = loginemail.text, let pass = loginpassword.text, email != "", pass != "" else {
        return false
    }
    Auth.auth().signIn(withEmail: email, password: pass) { (result, error) in
        if let error = error{
            TWMessageBarManager().showMessage(withTitle: "invalid email or pass", description: error.localizedDescription, type: .error)
            self.shouldPerformSegue = false

        } else {
        self.shouldPerformSegue = true
        }
    }
    return shouldPerformSegue
}

---

我的目标是使用故事板序列（特别是非自定义序列）来解决这个问题，可能吗？

尝试使用完成处理程序

func didUserLoggedInSuccessfully(success:@escaping (NSDictionary) -> Void)
    {
        Auth.auth().signIn(withEmail: self.emailTextField.text!, password: self.passwordTextField.text!) { (user, error) in
            if error == nil {
                success(true)
            }
            else{
                //Tells the user that there is an error and then gets firebase to tell them the error
                success(false)
            }
        }
    }

Usgae

self.didUserLoggedInSuccessfully { (success) in
            if success {
                /// Perform Segue
            }
            else{
                /// Do not Perform
            }
        }

---

这里有更准确的答案。这里我将

@escaping

类型从

NSDictionary

更改为

（Bool，Error？

），因为我们需要返回带有结果的完成时钟

func didUserLoggedInSuccessfully(success:@escaping (Bool, Error?) -> Void)
{
    Auth.auth().signIn(withEmail: self.emailTextField.text!, password: self.passwordTextField.text!) { (user, error) in
        if error == nil {
            success(true,nil)
        }
        else{
            success(false,error)
        }
    }
}


self.didUserLoggedInSuccessfully { (result,error) in
    if result {
        /// Perform Segue
    }
    else{
        /// Do not Perform
        TWMessageBarManager().showMessage(withTitle: "invalid email or pass", description: error.localizedDescription, type: .error)
    }
}

---

我是否应该调用shouldPerformWithIdentifier:sender:中的函数？是的，您可以，如果处理程序返回Success==True，您需要执行segue，只需在我编写的地方编写performsgue///perform segue谢谢您的帮助，但我想我仍在试图弄清楚segue的生命周期是什么。我在if success{self.performsgue（带标识符：String，sender:Any？）中编写了override func shouldPerformSegue（带标识符：String，sender:Any？）->Bool{guard let email=loginemail.text，let pass=loginpassword.text，email！=“”，pass！=“”否则{return false}didUserLoggedInSuccessfully{（成功）{self.performsgue）（带标识符：“loginSegue”，sender:UIViewController（））}}返回false}它可以工作。但是我有很多冗余，我想如果我调用performsguewithidentifier:sender:function，它似乎不会调用shouldPerformSeguewithIdentifier。我说的对吗？