Is there a way to grab the parent object from a subview? - swift

Question

I'm working on a crossword puzzle app for swift and I am having trouble getting a UIButton from a subview in the UIButton that is a textfield.
The text field takes up the space where the UIButton title should be, but when clicking on the textfield it doesn't click the UIButton.
The UIButton itself as of now, highlights all the UIButtons of the some column and row.
There a few things I've tried such as graving the superclass of the subview
var myButton: CustomButton = textfield.superclass as? CustomButton
and I also tried using
var myObject : CustomButton? {
return view.compactMap({$0 as? CustomButton }).first
}
In the CustomButton.swift
class CustomButton: UIButton {
var number: Int = 0
var letter: Character?
var textField: UITextField!
var cornerLabel: UILabel!
// this init will intialize the button through programatically
override init(frame: CGRect) {
super.init(frame: frame)
textField = UITextField(frame: CGRect(x: 0, y: 0, width: 50, height: 50))
textField.translatesAutoresizingMaskIntoConstraints = false
textField.center = .zero
textField.textAlignment = .center
textField.text = ""
I have a ButtonStore.swift that stores all the CustomButtons in the array so I can manage them and retrieve certain ones.
And the MainController.swift has all the reference CustomButton. I am using a UITextFieldDelegate from the MainController
class MainController : UIViewController, UITextFieldDelegate{
var buttonStore : ButtonStore!
#IBOutlet var A1 : CustomButton!
#IBAction func buttonIsPress(sender: CustomButton){
let button : CustomButton = sender
let identifier : String = sender.accessibilityIdentifier ?? ""
// Clear all backgroundbox back to white unless the background is black
buttonStore.removeHighlights()
// Highlight the button pressed and its column and row
buttonStore.highlightRowColumn(identifier: identifier)
}
func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool
{
print("something happened")
// TRIED RECEIVING THE CUSTOMBUTTON HERE
return true
}
The expected result is to have had the CustomButton trigger when textfield is pressed or grabbing the CustomButton of the textfield pressed so I use the CustomButton as reference.

Answer 1

You can get the superview by
if let button = textField.superview as? CustomButton {
// Do what you want to here
}

Answer 2

You can grab any superview or any parent view controller generically in a type safe way by walking up the responder chain (because both UIViewController and UIView inherit from UIResponder and implement its next method):
extension UIResponder {
func firstParent<T: UIResponder>(ofType type: T.Type ) -> T? {
return next as? T ?? next.flatMap { $0.firstParent(ofType: type) }
}
}
Use like:
if let button = textField.firstParent(ofType: CustomButton.self) {
//Do button stuff here
}
This method has the advantage that you can find the next parent of a particular type even if it isn't the immediate parent (ie you may have several views between the textfield and the CustomButton and this still works, while calling superview does not).