onPageFinished method

Implementation

@override
Future<String> onPageFinished() async {
  final completer = Completer<String>();
  _channel.setMethodCallHandler((call) async {
    if (call.method == 'webview-onHtml') {
      final html = call.arguments ?? '';
      completer.complete(html);
    }
  });
  return completer.future;
}