Call addScriptMessageHandler after adding WKWebView to view

Question

I have added WKWebView to view via code in my class which extends UIViewController class, I am able to call JS function from iOS storyboard buttons successfully.

However, I want JS to be able to tell Swift when an ajax post request is complete... Luckily I found this page... http://www.kinderas.com/technology/2014/6/15/wkwebview-and-javascript-in-ios-8-using-swift

var contentController = WKUserContentController()
contentController.addScriptMessageHandler(
    self,
    name: "callbackHandler"
)

var config = WKWebViewConfiguration()
config.userContentController = contentController

self.webView = WKWebView(
    frame: self.containerView.bounds,
    configuration: config
)

Here... I want to be able add script message handler after the webview is added to view.

Is it possible to call addScriptMessageHandler() after webview is already added to the view?

Answer 1

Yes, and it's really simple too:

let contentController = self.webView.configuration.userContentController
contentController.addScriptMessageHandler(self, name: "callbackHandler2")