Next/Done button using Swift with textFieldShouldReturn

Using tags makes it easier. Assign tags in ascending order to all the text fields you are using on your screen.

---

func textFieldShouldReturn(_ textField: UITextField) -> Bool {

    let textTag = textField.tag+1
    if let nextResponder = textField.superview?.viewWithTag(textTag) as UIResponder
    {
        //textField.resignFirstResponder()
        nextResponder.becomeFirstResponder()
    }
    else {
        // stop editing on pressing the done button on the last text field.

        self.view.endEditing(true)
    }
    return true
}

I was attempting to test my textfields in the SignUpWindowView.swift, which is where all of the textFields are created. But, since I place SignUpWindowView into my MainViewController as a subview, all of my UITextField "handling" needed to be done in the MainView and NOT its subview.

So here is my entire code (at the moment) for my MainViewController, which handles moving my SignUpWindowView up/down when the keyboard is shown/hidden and then moves from one field to the next. When the user is in the last text field (whose keyboard Next button is now set to Done in the subview) the keyboard tucks away and the user can then submit the form with a signup button.

MainViewController:

import UIKit

@objc protocol ViewControllerDelegate
{
    func keyboardWillShowWithSize(size:CGSize, andDuration duration:NSTimeInterval)
    func keyboardWillHideWithSize(size:CGSize,andDuration duration:NSTimeInterval)
}

class ViewController: UIViewController,UITextFieldDelegate
{
    var keyboardDelegate:ViewControllerDelegate?

    let signUpWindow=SignUpWindowView()
    let signUpWindowPosition:CGPoint=CGPointMake(505, 285)

    override func viewDidLoad()
    {
        super.viewDidLoad()

        // Keyboard Notifications
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)

        // set the textFieldDelegates
        signUpWindow.firstNameTextField.delegate=self
        signUpWindow.lastNameTextField.delegate=self
        signUpWindow.userNameTextField.delegate=self
        signUpWindow.passwordTextField.delegate=self
        signUpWindow.confirmPasswordTextField.delegate=self
        signUpWindow.emailTextField.delegate=self
    }


    func keyboardWillShow(notification: NSNotification)
    {
        var info:NSDictionary = notification.userInfo!
        let keyboardFrame = info[UIKeyboardFrameEndUserInfoKey] as! NSValue
        let keyboardSize = keyboardFrame.CGRectValue().size

        var keyboardHeight:CGFloat = keyboardSize.height

        let animationDurationValue = info[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber

        var animationDuration : NSTimeInterval = animationDurationValue.doubleValue

        self.keyboardDelegate?.keyboardWillShowWithSize(keyboardSize, andDuration: animationDuration)

        // push up the signUpWindow
        UIView.animateWithDuration(animationDuration, delay: 0.25, options: UIViewAnimationOptions.CurveEaseInOut, animations: {
            self.signUpWindow.frame = CGRectMake(self.signUpWindowPosition.x, (self.signUpWindowPosition.y - keyboardHeight+140), self.signUpWindow.bounds.width, self.signUpWindow.bounds.height)
            }, completion: nil)
    }

    func keyboardWillHide(notification: NSNotification)
    {
        var info:NSDictionary = notification.userInfo!

        let keyboardFrame = info[UIKeyboardFrameEndUserInfoKey] as! NSValue
        let keyboardSize = keyboardFrame.CGRectValue().size

        var keyboardHeight:CGFloat = keyboardSize.height

        let animationDurationValue = info[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber

        var animationDuration : NSTimeInterval = animationDurationValue.doubleValue

        self.keyboardDelegate?.keyboardWillHideWithSize(keyboardSize, andDuration: animationDuration)

        // pull signUpWindow back to its original position
        UIView.animateWithDuration(animationDuration, delay: 0.25, options: UIViewAnimationOptions.CurveEaseInOut, animations: {
            self.signUpWindow.frame = CGRectMake(self.signUpWindowPosition.x, self.signUpWindowPosition.y, self.signUpWindow.bounds.width, self.signUpWindow.bounds.height)
            }, completion: nil)
    }

    func textFieldShouldReturn(textField: UITextField) -> Bool
    {
        switch textField
        {
        case signUpWindow.firstNameTextField:
            signUpWindow.lastNameTextField.becomeFirstResponder()
            break
        case signUpWindow.lastNameTextField:
            signUpWindow.userNameTextField.becomeFirstResponder()
            break
        case signUpWindow.userNameTextField:
            signUpWindow.passwordTextField.becomeFirstResponder()
            break
        case signUpWindow.passwordTextField:
            signUpWindow.confirmPasswordTextField.becomeFirstResponder()
            break
        case signUpWindow.confirmPasswordTextField:
            signUpWindow.emailTextField.becomeFirstResponder()
            break
        default:
            textField.resignFirstResponder()
        }
        return true
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    override func viewWillDisappear(animated: Bool) {
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    }

    @IBAction func signup()
    {
        signUpWindow.frame=CGRectMake(signUpWindowPosition.x, signUpWindowPosition.y, 485,450)
        signUpWindow.backgroundColor=UIColor.clearColor()

        self.view.addSubview(signUpWindow)
    }
}

You need to implement UITextFieldDelegate in your class and set that object as the delegate for the UITextField. Then implement the method textFieldShouldReturn: like this:

func textFieldShouldReturn(textField: UITextField) -> Bool {
    textField.resignFirstResponder()
    if textField == someTextField { // Switch focus to other text field
        otherTextField.becomeFirstResponder()
    }
    return true
}

In your example you are missing this line:

confirmPasswordTextField.delegate = self

If you have implemented the delegate of course.