Flutter基础总结（1）状态栏切换和底部按的突出

新型冠状病毒成了2020年飞出来的一只黑天鹅。这只黑天鹅的出现，让多少企业、多少人乱了阵脚。但是，一切偶然的背后都是必然。

病毒让本来祥和快乐的新年压抑了很多，让2020年的开春蒙上了一层迷雾，但大家不要忘了，生活和工作还是要继续，特别是在武汉地区的朋友，我们一定要相信，任何困难都难不倒伟大的中国人，这是一种名族自信，众志成城，终将克服，迎来曙光。

1：效果图

image.png
image.png

2：废话就不读多说了 直接上代码

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

void main() {
  runApp(MyApp());
  if (Platform.isAndroid) {
var systemUiOverlayStyle =
    SystemUiOverlayStyle(statusBarColor: Colors.transparent);
/**
 * 设置系统用户界面叠加样式
 */
SystemChrome.setSystemUIOverlayStyle(systemUiOverlayStyle);
}
}

class HomePage extends StatefulWidget {
@override
State<StatefulWidget> createState() {
// TODO: implement createState
return HomePageState();
}
}

  /**
 * 主页面
 */
class HomePageState extends State<HomePage>
with SingleTickerProviderStateMixin {
List<String> _abs = ['A', 'B', 'C'];

//Tab
TabController _tabController;

//页面
PageController _pageController;

  @override
void initState() {
// TODO: implement initState
super.initState();
_tabController = TabController(length: _abs.length, vsync: this);
_pageController = PageController(initialPage: 0);
_tabController.addListener(() {
  if (_tabController.indexIsChanging) {
    _pageController.animateToPage(_tabController.index,
        duration: Duration(milliseconds: 300), curve: Curves.decelerate);
  }
});
}

@override
void dispose() {
// TODO: implement dispose
_tabController.dispose();
super.dispose();
}

@override
Widget build(BuildContext context) {
// TODO: implement build

return Scaffold(
  appBar: AppBar(
    title: Text("Deme"),
    centerTitle: true,
    automaticallyImplyLeading: true,
    actions: <Widget>[
      PopupMenuButton(
        onSelected: (val) {
          var position = -1;
          switch (val) {
            case 'A':
              position = 0;
              break;
            case 'B':
              position = 1;
              break;
            case 'C':
              position = 2;
              break;
          }
          _tabController.index = position;
        },
        icon: Icon(Icons.more_vert),
        itemBuilder: (context) => List.generate(
            _abs.length,
            (index) => PopupMenuItem(
                  value: _abs[index],
                  child: Text(_abs[index]),
                )),
      )
    ],
    bottom: TabBar(
        labelColor: Colors.red,
        unselectedLabelColor: Colors.white,
        controller: _tabController,
        isScrollable: false,
        indicatorColor: Colors.yellow,
        indicatorSize: TabBarIndicatorSize.tab,
        indicatorWeight: 5.0,
        tabs: List.generate(
            _abs.length,
            (index) => Tab(
                  text: _abs[index],
                  icon: Icon(Icons.android),
                ))),
  ),
  drawer: Drawer(
    child: SafeArea(
      child: Container(
        child: Text(
          'Drawer',
          style: TextStyle(
              color: Theme.of(context).primaryColor, fontSize: 30.0),
        ),
      ),
    ),
  ),
  body: PageView(
    controller: _pageController,
    /*   children: _abs
        .map((str) => TabChangePage(
      content: str,
    ))
        .toList(),*/
    children: _abs.map((str) {
      TabChangePage(
        content: str,
      );
    }).toList(),
    onPageChanged: (position) {
      _tabController.index = position;
    },
  ),
  bottomNavigationBar: BottomAppBar(
    shape: CircularNotchedRectangle(),
    child: Row(
      mainAxisSize: MainAxisSize.max,
      mainAxisAlignment: MainAxisAlignment.spaceAround,
      children: <Widget>[
        IconButton(
          icon: Icon(
            Icons.android,
            size: 30.0,
            color: Theme.of(context).primaryColor,
          ),
          onPressed: () {},
        ),
        IconButton(
          icon: Icon(
            Icons.phone_iphone,
            size: 30.0,
            color: Theme.of(context).primaryColor,
          ),
          onPressed: () {},
        )
      ],
    ),
  ),
  floatingActionButton: FloatingActionButton(
    onPressed: () => print('Add'),
    child: Icon(
      Icons.add,
      color: Colors.white,
    ),
    tooltip: "varenyzc",
  ),
  floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
);
}
}

class TabChangePage extends StatelessWidget {
final String content;

TabChangePage({Key key, this.content}) : super(key: key);

@override
Widget build(BuildContext context) {
// TODO: implement build
return SafeArea(
  child: Container(
    alignment: Alignment.center,
    child: Text(
      content,
      style:
          TextStyle(color: Theme.of(context).primaryColor, fontSize: 30.0),
    ),
  ),
);
;
}
}

class MyApp extends StatelessWidget {
@override
 Widget build(BuildContext context) {
// TODO: implement build
return MaterialApp(
  title: "DemoOne",
  debugShowCheckedModeBanner: false,
  home: HomePage(),
);
}
}

地址githup： https://github.com/xuezhihuixzh/Flutter_demo.git