Delegate function not being called iOS Swift - ios

Question

Here I am trying to pass value from one class LanguageSelectionTVC to another RegistrationVC by using a Protocol.
When I try and call the method self.delegate?.setSelectedLangauges(self.languagesSpokenArray) inside LanguageSelectionTVC it doesn't call the method setSelectedLangauges inside the class Registration VC could someone please suggest where I am going wrong ?
protocol LanguageSelectionTVCProtocol {
func setSelectedLangauges(_ valueSent: [String])
}
class LanguageSelectionTVC: UITableViewController {
var delegate : LanguageSelectionTVCProtocol? = nil
func saveAndClose() {
self.delegate?.setSelectedLangauges(self.languagesSpokenArray)
dismiss()
}
}
class RegistrationVC: UIViewController,
UITableViewDelegate,
UITableViewDataSource,
LanguageSelectionTVCProtocol{
func setSelectedLangauges(_ valueSent: [String]){
self.showLanguagesSpoken(valueSent)
}
}
Moving to LanguageSelectionTVC from RegistrationVC . The below tableView method is in my RegistrationVC
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let row = indexPath.row
let section = indexPath.section
let currentCell = tableView.cellForRow(at: indexPath) as! UITableViewCell
if section == 4 && row == 0 {
// The user has clicked on languages spoken cell
self.performSegue(withIdentifier: "LanguageSelectionTVC", sender: self)
}
}

Answer 1

You need to access LanguageSelectionTVC from preparForSegue to set delegate of it. So override the prepare(for:sender:) in your RegistrationVC.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "LanguageSelectionTVC" {
let vc = segue.destination as! LanguageSelectionTVC
vc.delegate = self
}
}

Answer 2

You need to set the delegate in RegistrationVC to LanguageSelectionTVC, for example you could set it when performing a segue:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let targetVC = segue.destination as! LanguageSelectionTVC
targetVC.delegate = self
}

Answer 3

You need to set delegate. can you please see below ready example for pass data between two view controller.
import UIKit
protocol SenderViewControllerDelegate
{
func messageData(str1:NSString)
}
class tableViewController: UIViewController, UITableViewDelegate,
UITableViewDataSource
{
var delegate: tableViewController?
override func viewDidLoad()
{
super.viewDidLoad()
self.delegate?.messageData(str1: “Hello world”)
}
}
receive data in below controller
import UIKit
class HomeViewController: UIViewController ,SenderViewControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let objtableview = tableViewController(nibName: "tableViewController",bundle: nil)
objtableview.delegate = self
self.navigationController?.pushViewController(objtableview, animated: true)
}
func messageData(str1:NSString){
print(str1)
}
}