How to know when my WKWebview derived subview is loaded in Swift - ios

Question

I have a view, which loads a subview after certain actions have happened, within the viewDidLoad() method:
override func viewDidLoad() {
super.viewDidLoad()
//OTHER STUFF...
let config = WKWebViewConfiguration()
config.userContentController = contentController
self.myWebView = WKWebView(
frame: self.containerView.bounds,
configuration: config
)
self.myWebView.navigationDelegate = self
self.view.addSubview(self.myWebView)
}
I need to do some checks once the web view has loaded. How can I do something like:
webSubviewDidLoad() {
//do stuff
}

Answer 1

there is a specific delegate didFinishNavigation
didFinishNavigation documentation
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let configuration = WKWebViewConfiguration()
let webView = WKWebView(frame: .zero, configuration: configuration)
webView.translatesAutoresizingMaskIntoConstraints = false
webView.navigationDelegate = self
view.addSubview(webView)
/* add layout constraints that make the webview fitting in your view */
if let url = URL(string: "https://google.com") {
webView.load(URLRequest(url: url))
}
}
}
extension ViewController: WKNavigationDelegate {
func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
print("Finished navigating to url \(webView.url)")
}
}
or you can check the estimatedProgress property for the progress
estimatedProgress documentation

Answer 2

Step 1. Add an observer to be notified when your web view finishes loading like below. This code should be placed within viewDidLoad method of your view controller class.
myWebView.addObserver(self, forKeyPath: #keyPath(WKWebView.isLoading), options: .new, context: nil)
Step 2. Implement the observeValue(forKeyPath:) method in your view controller, doing whatever actions you need to do like below.
override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
if keyPath == "isLoading" && !myWebView.isLoading {
// Do your needed action here
}
}

Answer 3

Implement your own WebView:
import WebKit
protocol WebViewDelegate {
func didLayoutSubviews()
}
class WebView : WKWebView {
weak var delegate: WebViewDelegate?
override func layoutSubviews() {
super.layoutSubviews()
self.delegate?.didLayoutSubviews()
}
}