Question

所以我正在尝试创建一个注册页面，我遇到了一些麻烦。我希望用户在注册之前填写所有信息。在他们点击注册按钮后，如果他们没有填写所有字段，他们会得到许多不同的UIAlertView错误。当我点击注册时，它会将用户带到下一页然后显示UIAlertView，我不希望这种情况发生。我无法弄清楚发生了什么。如果UIAlertView没有填写用户名或电子邮件，我需要在点击按钮后显示UIAlertView，而不是转到下一页。我的代码中有一个performSegue方法，但它首先执行，而不是最后执行。有谁能够帮我？我还将包括我的故事板的屏幕截图。

user.signUpInBackgroundWithBlock {
        (succeeded: Bool, error: NSError?) -> Void in
        if let error = error {
            let errorString = error.userInfo?["error"] as? NSString
            if fullname.isEmpty || email.isEmpty || username.isEmpty || password.isEmpty {
                var emptyFields:UIAlertView = UIAlertView(title: "Plese try again", message: "It looks like you forgot to fill out all the fields. Please make sure all the fields are filled out so we can create an account for you.", delegate: self, cancelButtonTitle: "Try again")

                emptyFields.show()
            } else if error.code == 203 {
                var takenEmail:UIAlertView = UIAlertView(title: "Please try again", message: "It looks like that email has already been taken, please try again.", delegate: self, cancelButtonTitle: "Try again")
            } else if error.code == 202 {
                var usernameTaken:UIAlertView = UIAlertView(title: "Please try again", message: "It looks like that username is already in use, please try again.", delegate: self, cancelButtonTitle: "Try again")
            }
        }
    }

Answer 1

有几种方法可以做到这一点。我这样做的方式如下。

第1步。好的，你想选择你的注册视图控制器。第2步。您将控制从黄色视图控制器图标单击并拖动到第二个视图控制器。在出现的菜单中，选择显示或呈现模态选项。

第3步。选择刚刚创建的Segue并更改其标识符，在右侧面板中选择＆＃34; signupSuccessful＆＃34;。

第4步。您可以像这样设置代码。

if usernameTF.text.isEmpty || passwordTF.text.isEmpty {
            var emptyFields = UIAlertView()
            emptyFields.title = "Plese try again"
            emptyFields.message = "It looks like you forgot to fill out all the fields. Please make sure all the fields are filled out so we can create an account for you."
            emptyFields.addButtonWithTitle("Try Again!")
            emptyFields.show()
        }else if usernameTF.text == "ERROR CODE 203" {
            //do same thing with the alert view!
        }else if usernameTF.text == "ERROR CODE 202" {
            //Do another alert view here
            //You can keep adding the "else ifs" for any other error codes
        }
        //Here is where it will send to the second view when everything above is false!
        else {
            //Here we present the second view.
            self.performSegueWithIdentifier("signupSuccessful", sender: self)
        }

你去吧。如果您需要再次查看segue或上述任何代码，请下载该项目。

https://github.com/bobm77/ParseSegueExample

Answer 2

在视图控制器中实施方法func shouldPerformSegueWithIdentifier(identifier: String?, sender: AnyObject?) -> Bool，如果您不希望发生segue，请返回false。

如果字段丢失，则将注册转到下一个视图控制器

2 个答案: