flutter 底部导航栏 BottomNavigationBar

话不多说，上代码

import 'package:flutter/material.dart';
import 'package:flutter_zhihu/pages/tabs/homeTab.dart';

class TabsController extends StatefulWidget {
  @override
  _TabsControllerState createState() => _TabsControllerState();
}

class _TabsControllerState extends State<TabsController> {

  int _currentIndex = 0;
  final pages = [HomeTab(),HomeTab(),HomeTab(),HomeTab(),HomeTab()];
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('标题'),
        actions: [
          IconButton(icon: Icon(Icons.search), onPressed: (){
            print('惦记了搜索');
          })
        ],
      ),
      bottomNavigationBar: BottomNavigationBar(
        items: bottomNavItems,//配置底部菜单
        currentIndex: _currentIndex,//当前菜单在第几个
        onTap: (index){
　　　　　　　　//菜单切换事件
            _changePage(index);
        },
        type: BottomNavigationBarType.fixed,//菜单切换效果
      ),
      body: pages[_currentIndex],//菜单页面切换
    );
  }

　//定义底部菜单
  final List<BottomNavigationBarItem> bottomNavItems  = [
    BottomNavigationBarItem(
      backgroundColor: Colors.blue,
      icon: Icon(Icons.home),
      label: '首页',
    ),
    BottomNavigationBarItem(
      backgroundColor: Colors.green,
      icon: Icon(Icons.message),
      label: '视频',
    ),
    BottomNavigationBarItem(
      backgroundColor: Colors.amber,
      icon: Icon(Icons.shopping_cart),
      label: '会员',
    ),
    BottomNavigationBarItem(
      backgroundColor: Colors.red,
      icon: Icon(Icons.person),
      label: '消息',
    ),
    BottomNavigationBarItem(
      backgroundColor: Colors.red,
      icon: Icon(Icons.person),
      label: '我的',
    ),
  ];

  /*切换页面*/
  void _changePage(int index) {
    /*如果点击的导航项不是当前项  切换 */
    if (index != _currentIndex) {
      setState(() {
        _currentIndex = index;
      });
    }
  }
}