Question

我正在寻找帮助关闭createuser vc并返回上一个初始vc，如果用户在firebase中的alreadyexists。

我目前有：

// Attempt to create a new user.  (authData = dictionary).
        FIREBASE_REF.createUser(email, password: password, withValueCompletionBlock: { (error, authData) in

// If there was no error then
            if error == nil {
// Authorise the new user into the application.  (authData = object).
                FIREBASE_REF.authUser(email, password: password, withCompletionBlock: { ( error, authData) in

                    if error == nil {
// Store the user id into the device.
                        NSUserDefaults.standardUserDefaults().setValue(authData.uid, forKey: "uid")
// Stop the activity indicator.
                        self.activityInd.stopAnimating()
// Close the create user screen.
                        self.dismissViewControllerAnimated(true, completion: nil)
                    }
                    else
                    {
// Stop the activity indicator.
                        self.activityInd.stopAnimating()

                        print(error)

                   }
                })
            }
            else

// USER ACCOUNT ALREADY EXISTS \\
            {
// Stop the activity indicator.
                self.activityInd.stopAnimating()

// Display an error message.
                let alertController = UIAlertController(title: "USER DUPLICATION ERROR", message:
                    "user account already exists, login as normal", preferredStyle: UIAlertControllerStyle.Alert)
                alertController.addAction(UIAlertAction(title: "Dismiss", style: UIAlertActionStyle.Default,handler: nil))
                self.presentViewController(alertController, animated: true, completion: nil)

// Close the create user screen.
                self.dismissViewControllerAnimated(true, completion: nil)

            }
      })

当用户创建一个新帐户时，self.dismissViewController工作正常并返回到初始vc，然后加载主页。但是，当已有用户时，self.dismissViewController不会执行任何操作。如果有人能够对此有所了解，那将非常感激。

此外，如果有人可以建议如何确保警报消息保持在屏幕上，直到用户在关闭vc之前选择解除，这也是有用的。

由于

Answer 1

问题解决了，如果有人对此感兴趣，那么我是如何解决问题的：

System.out.println("Please enter an initial deposit:");
            try{  

                deposit.add(keyboard.nextInt());

            }catch(NumberFormatException e){

                System.out.println("Invalid input");

            System.out.println("Please enter an account number:");
            accountNumber.add(keyboard.nextDouble());

从FIREBASE_REF块中快速关闭vc控制器

1 个答案: