lightspeed

A new Flutter package project.

开始使用

此项目是一个Dart包项目的起点， 一个包含可以轻松跨多个Flutter或Dart项目的代码的库模块。

有关如何开始使用Flutter的帮助，请参阅我们的 在线文档，其中提供了教程、示例、移动开发指南和完整的API参考。

使用示例

以下是如何在Flutter应用中使用lightspeed插件的示例。

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:lightspeed/lightspeed.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return MaterialApp(
title: ‘Flutter Demo’,
theme: ThemeData(
primarySwatch: Colors.amber,
),
home: const MyHomePage(title: ‘Flutter Demo Home Page’),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
final _controller = HomeController();
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
const Text(
‘你已经按了按钮多少次:’,
),
BuildController<HomeState>(
actions: {
Initialize: (state) => Text(’${state.value}’, style: Theme.of(context).textTheme.headline4?.copyWith(color: Colors.blue)),
Increment: (state) => Text(’${state.value}’, style: Theme.of(context).textTheme.headline4?.copyWith(color: Colors.green)),
Decrement: (state) => Text(’${state.value}’, style: Theme.of(context).textTheme.headline4?.copyWith(color: Colors.red)),
},
controller: _controller,
buildWhen: (state) => state.value < 5,
),
_controller.build<HomeState>(actions: {
Initialize: (state) => Text(’${state.value}’, style: Theme.of(context).textTheme.headline4?.copyWith(color: Colors.blue)),
Increment: (state) => Text(’${state.value}’, style: Theme.of(context).textTheme.headline4?.copyWith(color: Colors.green)),
Decrement: (state) => Text(’${state.value}’, style: Theme.of(context).textTheme.headline4?.copyWith(color: Colors.red)),
}),
],
),
),
floatingActionButton: Row(
mainAxisAlignment: MainAxisAlignment.end,
children: [
FloatingActionButton(
onPressed: _controller.increment,
tooltip: ‘增加’,
child: const Icon(Icons.add),
),
const SizedBox(width: 20),
FloatingActionButton(
onPressed: _controller.decrement,
tooltip: ‘减少’,
child: const Icon(Icons.remove),
),
],
), // 这个尾随逗号使自动格式化更美观。
);
}
}
class HomeController extends ValueNotifier<HomeState> {
HomeController() : super(Initialize());
void increment() => value = Increment(value.value + 1);
void decrement() => value = Decrement(value.value - 1);
}
abstract class HomeState {
final int value;
HomeState(this.value);
}
class Initialize extends HomeState {
Initialize() : super(0);
}
class Increment extends HomeState {
Increment(int value) : super(value);
}
class Decrement extends HomeState {
Decrement(int value) : super(value);
}