Flutter - How to get a Javascript callback in WebView?
Changing Survey.postMessage() to window.Survey.postMessage() may work. Im not sure how to use evalJavascipt with WebviewScaffold, i'm using like this:
final _webView = new FlutterWebviewPlugin();final Set<JavascriptChannel> jsChannels = [ JavascriptChannel( name: 'Survey', onMessageReceived: (JavascriptMessage message) { print(message.message); }),].toSet();_webView.launch(url, jsChannels);_webView.onStateChanged.listen((event) { if (event.type == WebViewState.finishLoad) { _webView.evalJavascript('Your Js Code' + 'window.Survey.postMessage("Your Return Mes.")'); }});