Send data from flutter to web app

[vinitk-aveosoft]

Hey forks, I am working on a app which needs a Rich text editor. I have designed editor using React and self hosted the build HTML, CSS, JS with "shelf" and "shelf_flutter_asset" and viewing it with WebView.

Operation 1: Sending onChange data from Web App Editor to Flutter and saving it on DB (Successful)
I used below code
Editor end:
((e) => { console.log("debouncedEditorData: ", e); window.chrome.webview.postMessage(e); })

Flutter end:
`webViewController.webMessage.listen(
    (event) async {
      kprint(
          title: 'webview', object: 'On Message from Window Webview : $event');
    },
  );`

Operation 2: I want to send data from flutter to editor so I can prefill it when the editor is loaded for the first time (Need help here)
I tried with triggering a demo function like below
kprint( title: 'WebView', object: await webViewController .executeScript('triggerCustomEvent();'));
Problem I am facing is that I was able to add a new function above the main function.
The main function is too huge after being compiled and I have no clue how to trigger the prefilling function.
Is there any other way to tackle this using some kind of anchor or any alternate approach.