WKWebView console log handling?

novacactus

Is there a way to simply programmatically view console logs generated inside of a WKWebView on both Android and iOS? I cannot find a reliable solution for this and need it for production logging. I am currently running a web app that I do not own in the WKWebView, so I cannot modify any of the web content.

https stackoverflow com a 50755886
This is the only viable solution I have found so far, but it requires overwriting the console log functionality in JS. This "theoretically" should work, but is definitely not the most ideal solution given that I do not own the JS source code I am running within the WKWebView.

LandLu

WKWebView is a webkit control of iOS and we can only consume it on the iOS platform.
https://stackoverflow.com/a/50755886/8354952
This thread has explained how to implement it on WKWebView. If you want a translation for Xamarin here it is:

[assembly: ExportRenderer(typeof(MyWebView), typeof(CustomWebViewRenderer))]
namespace App.iOS
{
    public class CustomWebViewRenderer : ViewRenderer<MyWebView, WKWebView>, IWKScriptMessageHandler
    {
        WKWebView _wkWebView;
        protected override void OnElementChanged(ElementChangedEventArgs<MyWebView> e)
        {
            base.OnElementChanged(e);

            if (Control == null)
            {
                var config = new WKWebViewConfiguration();
                config.UserContentController.AddScriptMessageHandler(this, "logging");
                _wkWebView = new WKWebView(Frame, config);
                SetNativeControl(_wkWebView);

                string js = @"var console = { log: function(msg){window.webkit.messageHandlers.logging.postMessage(msg) } };";
                _wkWebView.EvaluateJavaScript(new NSString(js), (result, error) =>
                {
                    if (error != null)
                        Console.WriteLine($"installation of console.log() failed: {0}", error);
                });
            }
            if (e.NewElement != null)
            {
                // Url is a custom bindable property of MyWebView
                // I used it here to load the webpage
                Control.LoadRequest(new NSUrlRequest(new NSUrl(Element.Url)));
            }
        }
        public void DidReceiveScriptMessage(WKUserContentController userContentController, WKScriptMessage message)
        {
            Console.WriteLine(message.Body);
        }
    }
}

And WebView on Android can print the log information directly.