Flutter - Navigation Drawer Left or Right

main.dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        primarySwatch: Colors.brown,
      ),
      home: new MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  var _scaffoldKey = new GlobalKey<ScaffoldState>();

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      key: _scaffoldKey,
      drawer: new AppDrawer(), // left side
      //endDrawer: new AppDrawer(), // right side
      appBar: new AppBar(
        title: new Text("Title"),
      ),
      body: new ListView(
        children: <Widget>[
          new ListTile(
            title: new Text("Body"),
          ),
          new ListTile(
            title: new RaisedButton(
              child: new Text("Open Drawer"),
              onPressed: () {
                _scaffoldKey.currentState.openDrawer(); // left side
                //_scaffoldKey.currentState.openEndDrawer(); // right side
              },
            ),
          ),
        ],
      ),
    );
  }
}


class AppDrawer extends StatefulWidget {
  @override
  _AppDrawerState createState() => new _AppDrawerState();
}

class _AppDrawerState extends State<AppDrawer> {
  @override
  Widget build(BuildContext context) {
    return new Drawer(
      child: new ListView(
        children: <Widget>[
          new DrawerHeader(
              child: new Text("Header"),
          ),
          new ListTile(
            title: new Text("Item 1"),
          ),
        ],
      ),
    );
  }
}