Platform Channel Flutter Code

main.dart

import 'package:flutter/material.dart';
import 'dart:async';
import 'package:flutter/services.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      home: new HomePage(),
    );
  }
}
class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: const Text('Native Code from Dart'),
      ),
      body: new MyHomePage(),
    );
  }
}
class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;
  @override
  _MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
  static const platform = const MethodChannel('flutter.native/helperChannel');
  String _responseFromNativeCode = 'Waiting for Response...';
  Future<void> responseFromNativeCode() async {
    String response = "";
    try {
      final String result = await platform.invokeMethod('helloFromNativeCode');
      response = result;
    } on PlatformException catch (e) {
      response = "Failed to Invoke: '${e.message}'.";
    }
    setState(() {
      _responseFromNativeCode = response;
    });
  }
  @override
  Widget build(BuildContext context) {
    return Material(
      child: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: [
            RaisedButton(
              child: Text('Call Native Method'),
              onPressed: responseFromNativeCode,
            ),
            Text(_responseFromNativeCode),
          ],
        ),
      ),
    );
  }
}