     }
 }
 
-extension ViewController : WKNavigationDelegate {
+extension ViewController: WKNavigationDelegate {
     func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
-        print("didFinish navigation:");
+        print("didFinish navigation:")
     }
 }
-
-
-
-


// Wrap the WKWebView webview to allow IB use

class MyWebView : WKWebView {
    required init?(coder: NSCoder) {
        let configuration = WKWebViewConfiguration()
        let controller = WKUserContentController()
        configuration.userContentController = controller;
        super.init(frame: CGRect.zero, configuration: configuration)
    }
}

    }
}

extension ViewController: WKScriptMessageHandler {
    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
        // Callback from javascript: window.webkit.messageHandlers.MyObserver.postMessage(message)
        let text = message.body as! String;
