Delegate methods not calling in UITextField custom subclass

Question

I am creating a custom subclass from UITextField class. I want to apply something while textfield is focused. But in my custom class my delegate methods are not calling.

I have create a subclass that extends UITextField class and make some customisation.

In TGTextField class:

class TGTextField: UITextField, UITextFieldDelegate {

required init(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)!
    delegate = self
    createBorder()
}
required override init(frame: CGRect) {
    super.init(frame: frame)
    delegate = self
    createBorder()
}
func createBorder(){
    self.layer.borderColor = AppColor.TextFieldColors.BorderNormalColor.cgColor
    self.layer.borderWidth = 1.0;
    self.layer.cornerRadius = 8
}

func textFieldDidBeginEditing(textField: UITextField) {
    print("focused")
    self.activeTextFieldColor()
}
func textFieldDidEndEditing(textField: UITextField) {
    print("lost focus")
     self.deactiveTextFieldColor()
}

func activeTextFieldColor(){
    self.layer.borderColor = AppColor.TextFieldColors.BorderActiveColor.cgColor
}
func deactiveTextFieldColor(){
    self.layer.borderColor = AppColor.TextFieldColors.BorderNormalColor.cgColor
}
}

Both these delegates methods are not called.

func textFieldDidBeginEditing(textField: UITextField) {
    print("focused")
    self.activeTextFieldColor()
}
func textFieldDidEndEditing(textField: UITextField) {
    print("lost focus")
     self.deactiveTextFieldColor()
}

You shouldn't implement the delegate methods here. Implement it where you are using TGTextField. — PGDev, Jul 26 '19 at 12:48
But There is a general behaviour that need to implement on all TGTextFields. — Muhammad Wasim, Jul 26 '19 at 12:51
Then you can add methods and call them from wherever you implement the delegate. — PGDev, Jul 26 '19 at 12:52
I think that will not solve the problem. Can you explain a little with example please ? — Muhammad Wasim, Jul 26 '19 at 13:00
@dahiya_boy Yes, it is being called and i can see the border that is created in init method. — Muhammad Wasim, Jul 26 '19 at 13:05
@MuhammadWasim Can you put the break point and confirm? In both init methods — dahiya_boy, Jul 26 '19 at 13:06
@dahiya_boy Yes break point stopped 3 times as i am having 3 TGTextField in first screen. — Muhammad Wasim, Jul 26 '19 at 13:10
@MuhammadWasim Rico is right .. check his answer. Its also can be a root cause of issue. — dahiya_boy, Jul 26 '19 at 13:10
His answer really make sense but that was also warning from Xcode and added _ but it is not the root of problem. — Muhammad Wasim, Jul 26 '19 at 13:14

RajeshKumar R · Accepted Answer · 2019-07-26T13:29:09.763

3

Your code works for me. These delegate methods in the custom class won't be called if you set text field delegate to the corresponding view controller after you've initialized the text fields.

To avoid this add target in TGTextField instead of UITextFieldDelegate

class TGTextField: UITextField {

    required init(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)!
        //delegate = self
        createBorder()
    }
    required override init(frame: CGRect) {
        super.init(frame: frame)
        //delegate = self
        createBorder()
    }
    func createBorder(){
        self.layer.borderColor = UIColor.red.cgColor
        self.layer.borderWidth = 1.0;
        self.layer.cornerRadius = 8
        addTarget(self, action: #selector(activeTextFieldColor), for: .editingDidBegin)
        addTarget(self, action: #selector(deactiveTextFieldColor), for: .editingDidEnd)
    }
    @objc func activeTextFieldColor(){
        self.layer.borderColor = UIColor.green.cgColor
    }
    @objc func deactiveTextFieldColor(){
        self.layer.borderColor = UIColor.red.cgColor
    }
}

edited Jul 26 '19 at 13:29

answered Jul 26 '19 at 13:21

RajeshKumar R

15,445
2
38
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Nice one, but still doesn't make sense that delegate is not working – Rico Crescenzio Jul 26 '19 at 13:24
Awesome Answer :) – steveSarsawa Jul 26 '19 at 13:25
Wowww ! Its superb awesome. It worked ! Have great evening. – Muhammad Wasim Jul 26 '19 at 13:26
@RicoCrescenzio For ex. If you have `var nameTextField = TGTextField()` in `LoginVC`. And in `LoginVC`'s 'viewDidLoad` if you set `nameTextField.delegate = self`, then delegate methods from the custom class won't be called – RajeshKumar R Jul 26 '19 at 13:27
1

@RajeshKumarR ah, right I didn't get what you mean, of course it will not work. This is the best approach btw – Rico Crescenzio Jul 26 '19 at 13:29
It really make sense! Appreciated ! – Muhammad Wasim Aug 01 '19 at 08:47

Rico Crescenzio · Answer 2 · 2019-07-26T13:08:48.457

1

Looks like you're implementing the wrong method signature; you should put _ before textField, like this

func textFieldDidBeginEditing(_ textField: UITextField) {}
func textFieldDidEndEditing(_ textField: UITextField) {}

Xcode should help you highlighting with a warning

Instance method 'textFieldDidBeginEditing(textField:)' nearly matches optional requirement 'textFieldDidBeginEditing' of protocol 'UITextFieldDelegate'

edited Jul 26 '19 at 13:08

answered Jul 26 '19 at 13:06

Rico Crescenzio

3,952
1
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1

Ohh Nice catch – dahiya_boy Jul 26 '19 at 13:08
@Rico Crescenzio Thanks a lot for looking at it with me. I did it and Still its same issue. – Muhammad Wasim Jul 26 '19 at 13:12
Mh, I tried in playground and it's working; try to `CMD + SHIFT + K` and run it again – Rico Crescenzio Jul 26 '19 at 13:13
Sadly, I have gone through code several time cleans project, Restart Xcode but still its basic implementation and its not working. – Muhammad Wasim Jul 26 '19 at 13:19
That's crazy, there must be something else – Rico Crescenzio Jul 26 '19 at 13:20
Are you using interface builder or manually adding the subview? If you're using the interface builder, are you sure you set up the custom class correctly? – Rico Crescenzio Jul 26 '19 at 13:22

Delegate methods not calling in UITextField custom subclass

2 Answers2