packages/flutter_tools/templates/create/lib/main.dart.tmpl

import 'package:flutter/material.dart';
{{#withDriverTest}}
import 'package:flutter_driver/driver_extension.dart';
{{/withDriverTest}}
{{#withPluginHook}}
import 'package:flutter/services.dart';
import 'package:{{pluginProjectName}}/{{pluginProjectName}}.dart';
{{/withPluginHook}}

void main() {
{{#withDriverTest}}
  // Enable integration testing with the Flutter Driver extension.
  // See https://flutter.io/testing/ for more info.
  enableFlutterDriverExtension();
{{/withDriverTest}}
  runApp(new MyApp());
}

{{^withPluginHook}}
class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see
        // the application has a blue toolbar. Then, without quitting
        // the app, try changing the primarySwatch below to Colors.green
        // and then invoke "hot reload" (press "r" in the console where
        // you ran "flutter run", or press Run > Hot Reload App in
        // IntelliJ). Notice that the counter didn't reset back to zero;
        // the application is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful,
  // meaning that it has a State object (defined below) that contains
  // fields that affect how it looks.

  // This class is the configuration for the state. It holds the
  // values (in this case the title) provided by the parent (in this
  // case the App widget) and used by the build method of the State.
  // Fields in a Widget subclass are always marked "final".

  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that
      // something has changed in this State, which causes it to rerun
      // the build method below so that the display can reflect the
      // updated values. If we changed _counter without calling
      // setState(), then the build method would not be called again,
      // and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance
    // as done by the _incrementCounter method above.
    // The Flutter framework has been optimized to make rerunning
    // build methods fast, so that you can just rebuild anything that
    // needs updating rather than having to individually change
    // instances of widgets.
    return new Scaffold(
      appBar: new AppBar(
        // Here we take the value from the MyHomePage object that
        // was created by the App.build method, and use it to set
        // our appbar title.
        title: new Text(widget.title),
      ),
      body: new Center(
        // Center is a layout widget. It takes a single child and
        // positions it in the middle of the parent.
        child: new Column(
          // Column is also layout widget. It takes a list of children
          // and arranges them vertically. By default, it sizes itself
          // to fit its children horizontally, and tries to be as tall
          // as its parent.
          //
          // Invoke "debug paint" (press "p" in the console where you
          // ran "flutter run", or select "Toggle Debug Paint" from the
          // Flutter tool window in IntelliJ) to see the wireframe for
          // each widget.
          //
          // Column has various properties to control how it sizes
          // itself and how it positions its children. Here we use
          // mainAxisAlignment to center the children vertically; the
          // main axis here is the vertical axis because Columns are
          // vertical (the cross axis would be horizontal).
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            new Text(
              'You have pushed the button this many times:',
            ),
            new Text(
              '${_counter}',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: new FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: new Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}
{{/withPluginHook}}
{{#withPluginHook}}
class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => new _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _platformVersion = 'Unknown';

  @override
  initState() {
    super.initState();
    initPlatformState();
  }

  // Platform messages are asynchronous, so we initialize in an async method.
  initPlatformState() async {
    String platformVersion;
    // Platform messages may fail, so we use a try/catch PlatformException.
    try {
      platformVersion = await {{pluginDartClass}}.platformVersion;
    } on PlatformException {
      platformVersion = 'Failed to get platform version.';
    }

    // If the widget was removed from the tree while the asynchronous platform
    // message was in flight, we want to discard the reply rather than calling
    // setState to update our non-existent appearance.
    if (!mounted)
      return;

    setState(() {
      _platformVersion = platformVersion;
    });
  }

  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      home: new Scaffold(
        appBar: new AppBar(
          title: new Text('Plugin example app'),
        ),
        body: new Center(
          child: new Text('Running on: $_platformVersion\n'),
        ),
      ),
    );
  }
}
{{/withPluginHook}}