How To Set Onchange Listener To Switch Using Flutter App

import 'package:flutter/material.dart';

void main() => runApp(new MyApp());



class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: MyHomePage(),
    );
  }
}
class MyHomePage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => MyHomePageState();

}

class MyHomePageState extends State<MyHomePage> {
  bool _isChecked = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Colors.lightGreen[700],
        title: Text("Swiutch Onchange Listener"),
      ),
      body: Column(
        children: <Widget>[
          Expanded(
            child: Center(
              child: Text(_isChecked ? "Switch On" : "Switch Off",
                  style: TextStyle(
                    fontSize: 20.0,
                    fontWeight: FontWeight.bold,
                    color: Colors.lightGreen[700],
                  )),
            ),
          ),
          Expanded(
              child: Container(
                height: 350.0,
                child: Column(
                  children: [
                    Switch(
                      activeColor: Colors.green,
                      value: _isChecked,
                      onChanged: (val) {
                        setState(() {
                          _isChecked = val;
                        });
                      },
                    ),
                  ],
                ),
              )),
        ],
      ),
    );
  }
}