Flutter购物车按钮插件cart_button的使用
Flutter购物车按钮插件cart_button的使用
cart_button
是一个完全可定制的 Flutter 小部件,用于获取计数。它适用于电子商务应用,用于获取购物车中的商品数量。
该插件是从 CartStepper 派生出来的。
参数
count
: int/double, 显示的数量stepper
: int/double, 增加或减少的数量size
: double, 小部件的大小axis
: Axis, 布局方向numberSize
: double, 数字间隔,默认为2onChanged
: Function, 必须设置以释放计数器style
: CartbuttonStyleelevation
: double, 在此小部件周围显示阴影defaultWidget
: 计数器等于0时的默认小部件onDefaultWidgetTapped
: 当默认小部件被点击时调用的额外空函数
CartButtonStyle:
activeForegroundColor
: Color, 计数大于0时的文本颜色activeBackgroundColor
: Color, 计数大于0时的背景颜色foregroundColor
: Color, 计数等于0时的文本颜色backgroundColor
: Color, 计数等于0时的背景颜色shape
: BoxShape,radius
: Radius, 此小部件的圆角,默认计算为圆角矩形BoxBorder
: 小部件的边框shadowColor
: ColortextStyle
,iconTheme
: const IconThemeData(),iconPlus
: IconData, 自定义加号图标iconMinus
: IconData, 自定义减号图标buttonAspectRatio
: 加号和减号按钮的宽高比,默认为1,elevation
: 小部件的阴影高度,
使用方法
创建一个用于显示和修改数字的小部件:
Widget _buildButton() {
return CartButtonInt(
count: _counter,
size: 30,
style: CartButtonTheme.of(context).copyWith(activeForegroundColor: Colors.purple,),
onChanged: (count) {
setState(() {
_counter = count;
});
},
);
}
示例代码
import 'package:flutter/material.dart';
import 'package:cart_button/cart_button.dart';
void main() => runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.purple,
),
home: const MyHomePage(
title: "Cart Button",
),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
[@override](/user/override)
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counterInit = 0;
int _counter = 1;
int _counterLimit = 1;
double _dCounter = 0.0;
[@override](/user/override)
void initState() {
super.initState();
}
[@override](/user/override)
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: ListView(
children: <Widget>[
Row(
children: [
Expanded(
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
const Center(
child: Padding(
padding: EdgeInsets.only(top: 8),
child: Text('正常用法:'),
),
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Padding(
padding: const EdgeInsets.all(8.0),
child: CartButtonInt(
style: CartButtonStyle.fromTheme(
Theme.of(context),
radius: Radius.zero,
),
elevation: 7,
value: _counterInit,
onChanged: (count) {
setState(() {
_counterInit = count;
});
},
defaultWidget: const Text('计数器等于0时的默认小部件。'),
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: CartButtonDouble(
value: _dCounter,
stepper: 0.01,
onChanged: (count) {
setState(() {
_dCounter = (count * 100).round() / 100;
});
},
),
),
],
),
],
),
),
Expanded(
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
const Center(
child: Padding(
padding: EdgeInsets.only(top: 25),
child: Text('垂直方向:'),
),
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Padding(
padding: const EdgeInsets.all(8.0),
child: CartButtonInt(
value: _counter,
axis: Axis.vertical,
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: CartButtonInt(
value: _counter,
axis: Axis.vertical,
style: CartButtonTheme.of(context).copyWith(
activeBackgroundColor: Colors.white,
activeForegroundColor: Colors.blue,
border: Border.all(
color: Colors.blue,
),
),
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: CartButtonDouble(
value: _dCounter,
stepper: 0.01,
axis: Axis.vertical,
onChanged: (count) {
setState(() {
_dCounter = (count * 100).round() / 100;
});
},
),
),
],
),
],
),
),
],
),
const Center(
child: Padding(
padding: EdgeInsets.only(top: 25),
child: Text('不同大小 / 颜色设置:'),
),
),
Wrap(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8),
child: Center(
child: CartButtonInt(
value: _counter,
size: 20,
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
),
Padding(
padding: const EdgeInsets.all(8),
child: Center(
child: CartButtonInt(
value: _counter,
size: 30,
style: const CartButtonStyle(
foregroundColor: Colors.red,
activeForegroundColor: Colors.white,
activeBackgroundColor: Colors.pinkAccent,
buttonAspectRatio: 1.5,
),
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
),
Padding(
padding: const EdgeInsets.all(8),
child: Center(
child: CartButtonInt(
value: _counter,
size: 30,
style: CartButtonStyle(
foregroundColor: Colors.black87,
activeForegroundColor: Colors.black87,
activeBackgroundColor: Colors.white,
border: Border.all(color: Colors.grey),
elevation: 0,
buttonAspectRatio: 1.5,
),
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
),
Padding(
padding: const EdgeInsets.all(8),
child: Center(
child: CartButtonInt(
value: _counter,
size: 30,
style: CartButtonStyle(
foregroundColor: Colors.black87,
activeForegroundColor: Colors.black87,
activeBackgroundColor: Colors.white,
border: Border.all(color: Colors.grey),
radius: const Radius.circular(8),
elevation: 0,
buttonAspectRatio: 1.5,
),
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
),
Padding(
padding: const EdgeInsets.all(8),
child: Center(
child: CartButtonInt(
value: _counter,
size: 30,
numberSize: 6,
style: const CartButtonStyle(
foregroundColor: Colors.red,
activeForegroundColor: Colors.white,
activeBackgroundColor: Colors.pinkAccent,
radius: Radius.zero,
),
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
),
Padding(
padding: const EdgeInsets.all(8),
child: Center(
child: CartButtonInt(
value: _counter,
size: 80,
onChanged: (count) {
setState(() {
_counter = count;
});
},
),
),
),
],
),
const Center(
child: Padding(
padding: EdgeInsets.only(top: 25),
child: Text('最小限制:'),
),
),
Center(
child: CartButtonInt(
value: _counterLimit,
style: CartButtonStyle.fromTheme(
Theme.of(context),
radius: const Radius.circular(3),
),
size: 30,
onChanged: (count) {
if (count < 1) {
ScaffoldMessenger.of(context).hideCurrentSnackBar();
ScaffoldMessenger.of(context).showSnackBar(const SnackBar(
content: Text('数量不能小于1。'),
backgroundColor: Colors.orangeAccent,
));
return;
}
setState(() {
_counterLimit = count;
});
},
),
),
const SizedBox(height: 50),
],
),
),
);
}
}
更多关于Flutter购物车按钮插件cart_button的使用的实战教程也可以访问 https://www.itying.com/category-92-b0.html
1 回复
更多关于Flutter购物车按钮插件cart_button的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
当然,以下是如何在Flutter项目中使用cart_button
插件的一个代码示例。cart_button
插件通常用于显示购物车图标及其数量,便于用户快速访问购物车页面。假设你已经将cart_button
插件添加到了你的pubspec.yaml
文件中。
首先,确保你的pubspec.yaml
文件中包含以下依赖项:
dependencies:
flutter:
sdk: flutter
cart_button: ^最新版本号 # 请替换为实际的最新版本号
然后,运行flutter pub get
来安装依赖项。
接下来,在你的Dart文件中,你可以按照以下方式使用CartButton
:
import 'package:flutter/material.dart';
import 'package:cart_button/cart_button.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@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<MyHomePage> {
int _cartItemCount = 0;
void _incrementCartItemCount() {
setState(() {
_cartItemCount++;
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Flutter Cart Button Demo'),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
// 添加购物车按钮
CartButton(
itemCount: _cartItemCount,
onPressed: () {
// 点击按钮时导航到购物车页面
Navigator.pushNamed(context, '/cart');
},
iconData: Icons.shopping_cart,
iconColor: Colors.black,
labelStyle: TextStyle(color: Colors.black),
backgroundColor: Colors.white,
),
SizedBox(height: 20),
// 添加一个按钮来增加购物车中的商品数量
ElevatedButton(
onPressed: _incrementCartItemCount,
child: Text('Add to Cart'),
),
],
),
),
);
}
}
// 假设你有一个购物车页面
class CartPage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Cart Page'),
),
body: Center(
child: Text('This is the cart page.'),
),
);
}
}
// 在你的应用中注册购物车页面的路由
class MyAppRouter {
static Route<dynamic> generateRoute(RouteSettings settings) {
switch (settings.name) {
case '/cart':
return MaterialPageRoute(builder: (_) => CartPage());
default:
return MaterialPageRoute(builder: (_) => MyHomePage());
}
}
}
void main() {
runApp(MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
onGenerateRoute: MyAppRouter.generateRoute,
home: MyHomePage(),
));
}
在这个示例中:
- 我们创建了一个
_MyHomePageState
类,该类包含一个_cartItemCount
变量来跟踪购物车中的商品数量。 CartButton
小部件被添加到页面中心,显示当前购物车中的商品数量。当用户点击按钮时,它会导航到购物车页面(/cart
)。- 我们还添加了一个
ElevatedButton
来增加购物车中的商品数量。 MyAppRouter
类用于处理应用中的路由,确保当用户点击购物车按钮时,可以导航到CartPage
。
请注意,你可能需要根据你的应用结构调整代码,特别是路由部分。希望这个示例能帮助你理解如何在Flutter项目中使用cart_button
插件。