1. Tab的简单使用了解
要实现tab(选项卡或者标签视图)需要用到三个组件:
- TabBar
- TabBarView
- TabController
这一块,我也不知道怎么整理了,直接提供代码吧:
import 'package:flutter/material.dart';void main() {runApp(MyApp());
}class MyApp extends StatelessWidget {const MyApp({super.key});Widget build(BuildContext context) {return MaterialApp(debugShowCheckedModeBanner: true,home: Home(),theme: ThemeData(appBarTheme: AppBarTheme(backgroundColor: Colors.yellow, // 设置导航栏颜色为蓝色)),);}
}class Home extends StatelessWidget {const Home({super.key});Widget build(BuildContext context) {return DefaultTabController(length: 3, child: Scaffold(appBar: AppBar(leading: IconButton(onPressed: () => debugPrint("navigation button is pressed."), icon: Icon(Icons.menu),tooltip: "Navigation",),actions: [IconButton(onPressed: () => debugPrint("navigation button is pressed."), icon: Icon(Icons.search),tooltip: "search",)],title: Text("App Demo"),elevation: 0.0,bottom: TabBar(unselectedLabelColor: Colors.black38,indicatorColor: Colors.black54,indicatorSize: TabBarIndicatorSize.label,indicatorWeight: 1.0,tabs: [Tab(icon: Icon(Icons.local_florist)),Tab(icon: Icon(Icons.change_history)),Tab(icon: Icon(Icons.directions_bike)),]),),body: TabBarView(children: [Icon(Icons.local_florist, size: 128.0, color: Colors.black12),Icon(Icons.change_history, size: 128.0, color: Colors.black12),Icon(Icons.directions_bike, size: 128.0, color: Colors.black12),]),));}
}
效果图如下:
2. Drawer 侧边栏简单使用
在手势在屏幕进行左滑手势时,可以通过设置drawer
属性,来实现侧边栏显示的效果。
侧边栏代码的实现如下(为了避免代码太长,新建一个实现Drawer视图的文件):
import 'package:flutter/material.dart';class DrawerDemo extends StatelessWidget {const DrawerDemo({super.key});Widget build(BuildContext context) {return Drawer(child: ListView(padding: EdgeInsets.zero,children: [// DrawerHeader(// decoration: BoxDecoration(// color: Colors.greenAccent// ),// child: Text("Header".toUpperCase()),// ),UserAccountsDrawerHeader(accountName: Text("zhuzhu", style: TextStyle(fontWeight: FontWeight.bold, color: Colors.black)), accountEmail: Text("zhuzhu@com.net", style: TextStyle(color: Colors.black),),currentAccountPicture: CircleAvatar(backgroundImage: NetworkImage("https://img1.baidu.com/it/u=1368815763,3761060632&fm=253&fmt=auto&app=138&f=JPEG?w=760&h=434"),),decoration: BoxDecoration(image: DecorationImage(image: NetworkImage("https://i-blog.csdnimg.cn/blog_migrate/41635df939e6dd13c6d5e2af785d358b.jpeg"),fit: BoxFit.cover,colorFilter: ColorFilter.mode(Colors.yellow.withAlpha(150), BlendMode.srcOver))),),ListTile(title: Text("Message", textAlign: TextAlign.right),trailing: Icon(Icons.message, color: Colors.black12, size: 22.0),onTap: () => Navigator.pop(context), // 关闭抽屉),ListTile(title: Text("Favorite", textAlign: TextAlign.right),trailing: Icon(Icons.favorite, color: Colors.black12, size: 22.0),onTap: () => Navigator.pop(context), // 关闭抽屉),ListTile(title: Text("Settings", textAlign: TextAlign.right),trailing: Icon(Icons.settings, color: Colors.black12, size: 22.0),onTap: () => Navigator.pop(context), // 关闭抽屉),],),);}
}
然后将DrawerDemo
添加到drawer
属性里,代码如下:
import 'package:flutter/material.dart';
import 'Demo/Drawer_demo.dart'; // 导入DrawerDemo所在的文件void main() {runApp(MyApp());
}class MyApp extends StatelessWidget {const MyApp({super.key});Widget build(BuildContext context) {return MaterialApp(debugShowCheckedModeBanner: true,home: Home(),theme: ThemeData(appBarTheme: AppBarTheme(backgroundColor: Colors.yellow, // 设置导航栏颜色为蓝色)),);}
}class Home extends StatelessWidget {const Home({super.key});Widget build(BuildContext context) {return DefaultTabController(length: 3, child: Scaffold(appBar: AppBar(leading: IconButton(onPressed: () => debugPrint("navigation button is pressed."), icon: Icon(Icons.menu),tooltip: "Navigation",),actions: [IconButton(onPressed: () => debugPrint("navigation button is pressed."), icon: Icon(Icons.search),tooltip: "search",)],title: Text("App Demo"),elevation: 0.0,bottom: TabBar(unselectedLabelColor: Colors.black38,indicatorColor: Colors.black54,indicatorSize: TabBarIndicatorSize.label,indicatorWeight: 1.0,tabs: [Tab(icon: Icon(Icons.local_florist)),Tab(icon: Icon(Icons.change_history)),Tab(icon: Icon(Icons.directions_bike)),]),),body: TabBarView(children: [Icon(Icons.local_florist, size: 128.0, color: Colors.black12),Icon(Icons.change_history, size: 128.0, color: Colors.black12),Icon(Icons.directions_bike, size: 128.0, color: Colors.black12),]),// 添加侧边栏, 用扫动的手势来显示这个侧边栏drawer: DrawerDemo()));}
}
效果如下:
3. 底部导航栏的添加
底部导航栏的添加,可以通过属性bottomNavigationBar
来设置,实现它需要用到这两个组件:
- BottomNavigationBar
- BottomNavigationBarItem
之前页面都是静态页面,创建的类也都是继承于StatelessWidget
,但是点击tabbar需要根据点击改变状态,所以,就需要用新的组件StatefulWidget
。这一次就先只记录怎么使用,后面有时间把这个控件的说明再补充上。
根据前面的代码,抽取出一些代码,并创建以下三个类:
- ExploreDemo
import 'package:flutter/material.dart';
import 'ListView_demo.dart';
import 'Drawer_demo.dart';class ExploreDemo extends StatelessWidget {Widget build(BuildContext context) {return DefaultTabController(length: 3, child: Scaffold(appBar: AppBar(leading: IconButton(onPressed: () => debugPrint("navigation button is pressed."), icon: Icon(Icons.menu),tooltip: "Navigation",),actions: [IconButton(onPressed: () => debugPrint("navigation button is pressed."), icon: Icon(Icons.search),tooltip: "search",)],title: Text("App Demo"),elevation: 0.0,bottom: TabBar(unselectedLabelColor: Colors.black38,indicatorColor: Colors.black54,indicatorSize: TabBarIndicatorSize.label,indicatorWeight: 1.0,tabs: [Tab(icon: Icon(Icons.local_florist)),Tab(icon: Icon(Icons.change_history)),Tab(icon: Icon(Icons.directions_bike)),]),),body: TabBarView(children: [ListViewDemo(),Icon(Icons.change_history, size: 128.0, color: Colors.black12),Icon(Icons.directions_bike, size: 128.0, color: Colors.black12),]),// 添加侧边栏, 用扫动的手势来显示这个侧边栏drawer: DrawerDemo()));}
}
- HistoryDemo
import 'package:flutter/material.dart';class HistoryDemo extends StatelessWidget {Widget build(BuildContext context) {return Scaffold(appBar: AppBar(title: Text("历史记录")),body: Container(child: Center(child: Text("历史记录"),),));}
}
- MyviewDemo
import 'package:flutter/material.dart';class MyviewDemo extends StatelessWidget {Widget build(BuildContext context) {return Scaffold(appBar: AppBar(title: Text("个人主页")),body: Container(child: Center(child: Text("个人主页"),),));}
}
基础工作做好后,在main.dart 文件中,实现如下代码:
import 'package:flutter/material.dart';
import 'Demo/Explore_demo.dart';
import 'Demo/History_demo.dart';
import 'Demo/MyView_demo.dart';void main() {runApp(MyApp());
}class MyApp extends StatelessWidget {const MyApp({super.key});Widget build(BuildContext context) {return MaterialApp(debugShowCheckedModeBanner: true,home: Home(),theme: ThemeData(appBarTheme: AppBarTheme(backgroundColor: Colors.yellow, // 设置导航栏颜色为蓝色)),);}
}class Home extends StatefulWidget {const Home({super.key});State<StatefulWidget> createState() {return _HomeState();}
}class _HomeState extends State<Home> {int _currentPageIndex = 0;// 提前创建3个视图,当点击tabbar的时候,调用setState的index来去对应的页面final List<Widget> pageLists = [ExploreDemo(),HistoryDemo(),MyviewDemo()];void _onTapHandler (int index) {// 更新状态setState(() {_currentPageIndex = index;});}Widget build(BuildContext context) {return Scaffold(// 根据_currentPageIndex展示视图body: pageLists[_currentPageIndex],// 设置底部tabbarbottomNavigationBar: BottomNavigationBar(currentIndex: _currentPageIndex,onTap: _onTapHandler,type: BottomNavigationBarType.fixed,fixedColor: Colors.black,items: [BottomNavigationBarItem(icon: Icon(Icons.explore),label: "explore"),BottomNavigationBarItem(icon: Icon(Icons.history),label: "history"),BottomNavigationBarItem(icon: Icon(Icons.person),label: "My"),]));}
}
效果图如下: