Can a WKWebView call a function in the main app and get a value back?

Question

I am currently writing a web page that is designed to be run inside a WKWebView on iOS, or a WebView on Android.On Android, it is possible for the WebView to call a function that executes native app code and returns a value back to the WebView. Is it possible to do the same on iOS? Can I call a native iOS function and get a value returned back from it, in one way or another?

Answer 1

It certainly is possible, but needs a lot of preparation work. I made this a few years ago https://github.com/ddaddy/DJJavaInsertion when I needed to be able to control how an app works by changing JavaScript on a webpage. It uses UIWebView but you should be able to modify it to use WKWebView

The way it works is it loads your web page and kicks off an initial js function. As your js needs to call an Obj-C method it makes an iframe call to a specially formulated url which the webview delegate catches and performs the function.

I used it to present native alerts, request data input and even perform quite complex web requests.

I doubt it'll be a drop in for you, but may show you how to do it.