UIWebView delegates don't fire in a custom class - ios

Question

I spent around 5 hours searching on StackOverFlow about how to implement this and I still not found a solution yet!
I have created a new iOS Swift app just to explain you what exactly I am trying to resolve.
First, I have a UIButton on main storyboard and when you click on it, it creates a new object from class WebViewAsPopup which creates programmatically a new WebView and a background as UIView with alpha 0.5, add some styling and then it add them to the main view controller ViewController as a popup.
Secondly, I couldn't set a delegate to those WebView's to handle UIWebViewDelegate and listen to both webViewDidStartLoad and webViewDidFinishLoad
Here's my code:
ViewController.swift
//
// ViewController.swift
// MySimpleApp
//
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var showPopupBtn: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func showPopupTapped(_ sender: Any) {
let popup = WebViewAsPopup()
popup.showWebViewPopup(on: self)
}
}
WebViewAsPopup.swift
//
// WebViewAsPopup.swift
// MySimpleApp
//
import WebKit
class WebViewAsPopup: NSObject, UIWebViewDelegate {
func showWebViewPopup(on controller: UIViewController) {
// Popup background
let bg = UIView()
bg.frame = CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
bg.layer.backgroundColor = UIColor.black.withAlphaComponent(0.5).cgColor
// Webview sizing
let width = UIScreen.main.bounds.width - 60
let height = UIScreen.main.bounds.height - 200
let x = UIScreen.main.bounds.width/2 - width/2
let y = UIScreen.main.bounds.height/2 - height/2
// Webview stuff
let webView = UIWebView()
webView.frame = CGRect(x: x, y: y, width: width, height: height)
let url = URL(string: "https://google.com")
let request = URLRequest(url: url!)
// webView.delegate = self << it crash here
webView.loadRequest(request)
// Styling webview popup
webView.layer.borderWidth = 1
webView.layer.borderColor = UIColor.black.cgColor
webView.layer.masksToBounds = true
webView.layer.cornerRadius = 10
// Add bg then webview to main view controller
controller.view.addSubview(bg)
controller.view.addSubview(webView)
}
func webViewDidStartLoad(_ webView: UIWebView)
{
print("#webViewDidStartLoad!") // << it doesn't fire :(
}
func webViewDidFinishLoad(_ webView: UIWebView)
{
print("#webViewDidFinishLoad!") // << it doesn't fire :(
}
}

Answer 1

As I noted in my comments, you need to save the popup object somewhere in order to retain it. If not (as in your example code), then it will be deallocated as soon as the action method showPopupTapped(_:) is completed.
Try this:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var showPopupBtn: UIButton!
let popup = WebViewAsPopup()
#IBAction func showPopupTapped(_ sender: Any) {
self.popup.showWebViewPopup(on: self)
}
}
Bonus Note:
If you're wondering why you don't need to do the same to the background view and web view in your popup object, that's because views automatically retain their subviews.
So, once you add your background view and web view as subviews to a parent view, their retain count goes up and will survive their current scope.