Flutter状态管理-FlyingRedux

秋天里的麦子 Flutter 2023-08-09 17 0 原文

简介

Flying Redux 是一个基于Redux状态管理的组装式flutter应用框架。

flying-redux

它有四个特性:

函数式编程

可预测的状态

插拔式的组件化

支持null safety 和 flutter 3.x

如何开始

以计数器为例，仅需要5步即可使用flying redux构建应用：

引入 flying_redux

创建状态类和初始化状态

定义 Action 和 ActionCreator

创建修改状态的 Reducer

创建组件或页面视图以显示

import 'package:flying_redux/flying_redux.dart';

/// [State]
class PageState extends Cloneable<PageState> {
  late int count;

  @override
  PageState clone() {
    return PageState()..count = count;
  }
}

/// [InitState]
PageState initState(Map<String, dynamic>? args) {
  //just do something here...
  return PageState()..count = 0;
}

/// [Action]
enum CounterAction { increment }

/// [ActionCreator]
class CounterActionCreator {
  static Action increment() {
    return const Action(CounterAction.increment, payload: 1);
  }
}

/// [Reducer]
buildReducer() {
  return asReducer(<Object, Reducer<PageState>>{
    CounterAction.increment: _increment,
  });
}

PageState _increment(PageState state, Action action) {
  final int num = action.payload;
  return state.clone()..count = (state.count + num);
}

/// [Page]
class CountPage extends Page<PageState, Map<String, dynamic>> {
  CountPage()
      : super(
            initState: initState,
            reducer: buildReducer(),
            view: (PageState state, Dispatch dispatch, ComponentContext<PageState> ctx) {
              return Scaffold(
                body: Center(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: <Widget>[
                      const Text(
                        'You have pushed the button this many times:',
                      ),
                      Text(state.count.toString()),
                    ],
                  ),
                ),
                floatingActionButton: FloatingActionButton(
                  onPressed: () => dispatch(CounterActionCreator.increment()),
                  tooltip: 'Increment',
                  child: const Icon(Icons.add),
                ), // This trailing comma makes auto-formatting nicer for build methods.
              );
            });
}