How to inject JavaScript callback to detect onclick event, using iOS WKWebView?

Question

I\'m using a WKWebView to show a website which has some HTML that includes three buttons. I want to run some Swift code in the native app when a specific button is

Answer 1

Here goes the implementation in detail:

 var webView: WKWebView?
 var webConfig:WKWebViewConfiguration {
 get {

    let webCfg:WKWebViewConfiguration = WKWebViewConfiguration()
    let userController:WKUserContentController = WKUserContentController()
    userController.add(self, name: "submit")
    let js:String = buttonClickEventTriggered()
    let userScript:WKUserScript =  WKUserScript(source: js, injectionTime:WKUserScriptInjectionTime.atDocumentEnd, forMainFrameOnly: false)
    userController.addUserScript(userScript)
    webCfg.userContentController = userController;
    return webCfg;
}
}
override func viewDidLoad() {
super.viewDidLoad()
self.webView = WKWebView(frame: self.view.frame, configuration: webConfig)
self.webView!.navigationDelegate = self
self.view = webView!
let url = URL(string:"your URL here")
let req = NSURLRequest(url:url! as URL)
self.webView!.load(req as URLRequest)
}

 func buttonClickEventTriggered() ->String{

let script:String = "document.getElementById('your button id here').addEventListener('click', function () {window.webkit.messageHandlers.submit.postMessage('submited');});"//Make sure you have mapped the name correctly under userController.add
return script;
}
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
print("Sucessss")
if(message.name == "submit") {
    print("It does ! \(message.body)")
    // Your code goes here
}
}