How to render partial content of a website in Flutter?
What do I have to do to display this content in an WebView inside my Flutter application?
This answer demonstrates how to pass html content to a Webview plugin in Flutter. In your case you dont need to read from a file as in that answer, just pass in the String that you obtain from whatever means you need to use.
The relevant part of that answers code for you is:
String fileText = await rootBundle.loadString('assets/help.html'); _controller.loadUrl( Uri.dataFromString( fileText, mimeType: 'text/html', encoding: Encoding.getByName('utf-8') ).toString());
where in your case the
fileTextString is the html content that you got from somewhere.