Set delegate for textField in ViewController that is owner of .xib - ios

Question

I am trying to use an xib file to display a custom alter view. For that purpose i use the SimpleAlert from here. I have the .xib file with my textFields in it and as the owner of the .xib i set the ViewController is created.
import UIKit
class TestBaumViewController: UIViewController, UITextFieldDelegate {
#IBOutlet weak var tfFirst: UITextField!
#IBOutlet weak var tfSecond: UITextField!
#IBOutlet weak var tfThird: UITextField!
#IBOutlet weak var tfFourth: UITextField!
init() {
super.init(nibName: "TestBaumViewController", bundle: nil)
initializeTextFields()
}
required init(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
//initializeTextFields()
}
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
//initializeTextFields()
}
override func awakeFromNib() {
super.awakeFromNib()
//initializeTextFields()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func initializeTextFields() {
tfFirst.delegate = self // Error Here!
tfFirst.keyboardType = UIKeyboardType.ASCIICapable
tfSecond.delegate = self
tfSecond.keyboardType = UIKeyboardType.NumberPad
tfThird.delegate = self
tfThird.keyboardType = UIKeyboardType.ASCIICapable
tfFourth.delegate = self
tfFourth.keyboardType = UIKeyboardType.NumberPad
}
func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
var result = true
let prospectiveText = (textField.text as NSString).stringByReplacingCharactersInRange(range , withString: string)
if textField == tfFirst {
if count(string) > 0 {
let disallowedCharacterSet = NSCharacterSet(charactersInString: "BW").invertedSet
let replacementStringIsLegal = string.rangeOfCharacterFromSet(disallowedCharacterSet) == nil
let resultingStringLengthIsLegal = count(prospectiveText) <= 1
result = replacementStringIsLegal && resultingStringLengthIsLegal
}
}
if textField == tfSecond {
if count(string) > 0 {
let disallowedCharacterSet = NSCharacterSet(charactersInString: "0123456789").invertedSet
let replacementStringIsLegal = string.rangeOfCharacterFromSet(disallowedCharacterSet) == nil
let resultingStringLenthIsLegel = count(prospectiveText) <= 3
result = replacementStringIsLegal && resultingStringLenthIsLegel
}
}
if textField == tfThird {
if count(string) > 0 {
let disallowedCharacterSet = NSCharacterSet(charactersInString: "abcdefghijklmnopqrstuvwxyz").invertedSet
let replacementStringIsLegal = string.rangeOfCharacterFromSet(disallowedCharacterSet) == nil
let resultingStringLenthIsLegel = count(prospectiveText) <= 1
result = replacementStringIsLegal && resultingStringLenthIsLegel
}
}
if textField == tfFourth {
if count(string) > 0 {
let disallowedCharacterSet = NSCharacterSet(charactersInString: "0123456789").invertedSet
let replacementStringIsLegal = string.rangeOfCharacterFromSet(disallowedCharacterSet) == nil
let resultingStringLenthIsLegel = count(prospectiveText) <= 3
result = replacementStringIsLegal && resultingStringLenthIsLegel
}
}
return result
}
As you can see i added IBOutlets for my textfields and now i wanted to add this view controller as their delegate. So i can check what was entered in the textfields.
I tried different approaches. First i tried putting the textfield.delegate = self into the viewDidLoad method but there i get an error "fatal error: unexpectedly found nil while unwrapping an Optional value" i think that is because the textfield aren't created jet. Next it tried the viewDidAppear method, with the same result. And finally, after i added an Object to the .xib with the view controller class set as its class to get the awakeFromNib method to fire, i put the textfield.delegate = self into that method. But i get the same error here.
Is there something i did not think of or am i doing something that will not be working?
regards Adarkas

Answer 1

Since you have already declared that your controller is conforming to the UITextFieldDelegate protocol, do this in the Interface Builder:
Select your textfield
Show Connections Inspector
There will be an Outlets section with delegate under it.
Drag the circle on the right of delegate to your View Controller object as shown under
Do this for every textField
The textField delegate methods should be called properly now.

Answer 2

What about didSet?
class TestBaumViewController: UIViewController, UITextFieldDelegate {
#IBOutlet weak var tfFirst: UITextField! {
didSet {
tfFirst.delegate = self
}
}
...
Or you can also drag the text fields delegates in the XIB.
Right click on the text field and drag the delegate property to the view controller.