Can I chain delegates together? - ios

Question

Swift 4.0 iOS 11.x
I have created a simple text field class, that uses the UITextFieldDelegate. I wanted to add to it an additional protocol that I could use to pass on the fact that the text entry to said field completed. A Delegate chain, since once I have picked up the fact that text entry has exited in the custom class I cannot pass it down to the VC in which the UITextField class is within it seems.
import UIKit
protocol ExitedFieldDelegate {
func exited(info: String)
}
class IDText: UITextField, UITextFieldDelegate {
internal var zeus: ExitedFieldDelegate? = nil
required init(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)!
delegate = self
}
required override init(frame: CGRect) {
super.init(frame: frame)
delegate = self
}
func textFieldDidBeginEditing(_ textField: UITextField) {
self.textColor = UIColor.black
}
func textFieldDidEndEditing(_ textField: UITextField, reason: UITextFieldDidEndEditingReason) {
if (delegate != nil) {
let info = self.text
zeus?.exited(info: info!)
}
}
}
I added this code to the viewController I wanted to use my custom class within.
class ConfigViewController: UIViewController, ExitedFieldDelegate
And of course the method required by the protocol
func exited(info: String) {
print("The brain has left the room")
}
And I made it a delegate of said protocol so I got this in effect
var blah = IDText()
blah.delegate = self
But well it doesn't work. Am I attempting the impossible here, should I simply use default notifications instead? or indeed something else?

Answer 1

By setting:
blah.delegate = self
You are overwriting setting the delegate to self in the initializers.
What you want is to rewrite:
internal var zeus: ExitedFieldDelegate? = nil
to:
weak var zeus: ExitedFieldDelegate?
To be able to use weak (you want that to prevent retain cycle), update protocol definition to:
protocol ExitedFieldDelegate: class {
func exited(info: String)
}
And then change this:
var blah = IDText()
blah.delegate = self
to:
var blah = IDText()
// you want to set zeus instead of the delegate field
blah.zeus = self