Add flutter to android app

gistfile1.txt

// Android
startActivity(
            FlutterActivity
                .withCachedEngine("my_engine_id")
                .build(this))


val mc = BasicMessageChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL, StringCodec.INSTANCE)
        mc.send(Gson().toJson(quote))
        
-----
// Flutter

static const BasicMessageChannel<String> platform =
      BasicMessageChannel<String>('flutter.dev/add2toApp', StringCodec());
  Map<dynamic, dynamic> _data = {};

  @override
  void initState() {
    super.initState();
    platform.setMessageHandler(_handlePlatformIncrement);
  }

  Future<String> _handlePlatformIncrement(String message) async {
    final response = await json.decode(message);
    setState(() {
      _data = response;
    });
    return message;
  }