flutter---抽屉Drawer and endDrawer

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(

        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(),
    );
  }
}

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

class _MyHomePageState extends State {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('左右抽屉'),
        //通过Scaffold.of(context)可以获取父级最近的Scaffold Widget的State对象
        leading: Builder(builder: (context){
          return IconButton(
            icon: Icon(Icons.assistant),
            onPressed: (){
              Scaffold.of(context).openDrawer();
            },
          );
        }),
        actions: [
          Builder(builder: (context){
            return IconButton(
              icon: Icon(Icons.add),
              onPressed: (){
                Scaffold.of(context).openEndDrawer();
              },
            );
          })
        ],
      ),
      drawer: Drawer(
        child: Center(
          child: Text('左抽屉'),
        ),
      ),
      endDrawer: Drawer(
        child: Center(
          child: Text('右抽屉'),
        ),
      ),
    );
  }
}