ios - Handling JavaScript events in WKWebView

Question

I'm trying to catch every onClick event in WKWebView. The website is working only with JavaScript so I cannot handle anything in:

func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void)

How can I do this?

Answer 1

you can use a WKUserScript and add it to the userContentController of the WKWebView's configuration.

    let config = WKWebViewConfiguration()
    let source = "document.addEventListener('click', function(){ window.webkit.messageHandlers.iosListener.postMessage('click clack!'); })"
    let script = WKUserScript(source: source, injectionTime: .atDocumentEnd, forMainFrameOnly: false)
    config.userContentController.addUserScript(script)
    config.userContentController.add(self, name: "iosListener")
    webView = WKWebView(frame: UIScreen.main.bounds, configuration: config)

this will make the script and inject it into the page when the document is finished loading. Now, you need to implement the WKScriptMessageHandler protocol to receive the message:

    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
        print("message: (message.body)")
        // and whatever other actions you want to take
    }