focusing a text field in swift

theTextFieldYouWant.becomeFirstResponder()

This works for me:

import UIKitclass ViewController:UIViewController, UITextFieldDelegate {    @IBOutlet weak var fNameField: UITextField!    @IBOutlet weak var sNameField: UITextField!    @IBOutlet weak var emailField: UITextField!    @IBOutlet weak var passwordField: UITextField!    override func viewDidLoad() {        super.viewDidLoad()        fNameField.delegate = self        sNameField.delegate = self        emailField.delegate = self        passwordField.delegate = self    }    func isValidEmail (test:String) ->Bool{        // your email validation here...        return true    }    func textFieldShouldReturn(textField: UITextField) -> Bool {        textField.resignFirstResponder()        if (textField == self.fNameField) {            self.sNameField.becomeFirstResponder()        }        else if (textField == self.sNameField) {            self.emailField.becomeFirstResponder()        } else if (textField == self.emailField) {            self.passwordField.becomeFirstResponder()        }        else{            var thereWereErrors = checkForErrors()            if !thereWereErrors            {                //conditionally segue to next screen            }        }        return true    }    func checkForErrors() -> Bool    {        var errors = false        let title = "Error"        var message = ""        if fNameField.text.isEmpty {            errors = true            message += "First name empty"            alertWithTitle(title, message: message, ViewController: self, toFocus:self.fNameField)        }        else if sNameField.text.isEmpty        {            errors = true            message += "Surname empty"            alertWithTitle(title, message: message, ViewController: self, toFocus:self.sNameField)            self.sNameField.becomeFirstResponder()        }        else if emailField.text.isEmpty        {            errors = true            message += "Email empty"            alertWithTitle(title, message: message, ViewController: self, toFocus:self.emailField)        }        else if !isValidEmail(emailField.text)        {            errors = true            message += "Invalid Email Address"            alertWithTitle(title, message: message, ViewController: self, toFocus:self.emailField)        }        else if passwordField.text.isEmpty        {            errors = true            message += "Password empty"            alertWithTitle(title, message: message, ViewController: self, toFocus:passwordField)        }        else if count(passwordField.text.utf16)<8        {            errors = true            message += "Password must be at least 8 characters"            alertWithTitle(title, message: message, ViewController: self, toFocus:self.passwordField)        }        return errors    }    func alertWithTitle(title: String!, message: String, ViewController: UIViewController, toFocus:UITextField) {        let alert = UIAlertController(title: title, message: message, preferredStyle: .Alert)        let action = UIAlertAction(title: "OK", style: UIAlertActionStyle.Cancel,handler: {_ in            toFocus.becomeFirstResponder()        });        alert.addAction(action)        ViewController.presentViewController(alert, animated: true, completion:nil)    }}