React Native 添加 Redux 支持

react

0x1 前言

之前写的项目都是人家编写好的脚手架,里面包含项目所需的环境文件,但由于有些东西用不到打包增加软件体积,所以自己从头搭建个环境。是基于 Native Base + react-navigation + Redux 的 react Native 脚手架,现在项目环境如下:

{

"name": "app",

"version": "0.0.1",

"private": true,

"scripts": {

"start": "react-native start",

"test": "jest",

"lint": "eslint ."

},

"dependencies": {

"native-base": "^2.13.4",

"react": "16.8.6",

"react-native": "0.60.5",

"react-native-gesture-handler": "^1.3.0",

"react-native-keyboard-aware-scroll-view": "^0.9.1",

"react-native-reanimated": "^1.2.0",

"react-navigation": "^3.11.1"

},

"devDependencies": {

"@babel/core": "^7.5.5",

"@babel/runtime": "^7.5.5",

"@react-native-community/eslint-config": "^0.0.5",

"babel-eslint": "7.2.3",

"babel-jest": "^24.8.0",

"eslint": "4.4.1",

"eslint-plugin-flowtype": "2.35.0",

"eslint-plugin-import": "2.7.0",

"eslint-plugin-jsx-a11y": "6.0.2",

"eslint-plugin-prettier": "2.1.2",

"eslint-plugin-react": "7.1.0",

"eslint-plugin-react-native": "3.0.1",

"jest": "^24.8.0",

"metro-react-native-babel-preset": "^0.56.0",

"prettier": "1.5.3",

"react-test-renderer": "16.8.6"

},

"jest": {

"preset": "react-native"

}

}

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0x2 添加 Redux 支持

这里大概讲解下安装类库支持:

yarn add yarn add react-navigation react-native-gesture-handler react-native-reanimated native-base

链接字体库资源:

react-native link

react-navigation 在 Android 环境额外添加代码支持,具体情况文档: MainActivity.java

react-navigation 在 react-native 版本大于 0.60 的时候不需要执行 react-native link 链接。

由于项目需要状态管理支持,故添加 Redux 状态管理类库支持,在 React Native 环境下和 React 项目一样:

yarn add redux react-redux redux-logger

redux-logger 是监控状态数据流日志,可以在控制台输出状态值的信息。

由于项目基本环境是 Native Base 环境,这里怎么安装它就不再描述了,故在基础项目下添加项目支持 Redux 即可。打开 ./src/App.js 添加 Redux 能力支持:

import {Root} from "native-base";

import {createStackNavigator, createAppContainer} from "react-navigation";

import {applyMiddleware, createStore} from "redux";

import {Provider} from "react-redux";

import React from "react";

import logger from "redux-logger";

import allReducers from "./store";

import reduxDemo from "./screens/reduxDemo";

const store = createStore(

allReducers,

applyMiddleware(logger)

); // 创建 Store

const AppNavigator = createStackNavigator(

{

ReduxDemo: {screen: reduxDemo},

},

{

initialRouteName: "ReduxDemo", // 路由入口

headerMode: "none", // 由于 react-navigation 默认导航栏自定义效果很差,故隐藏

},

);

const AppContainer = createAppContainer(AppNavigator);

export default () => (

<Provider store={store}>

<Root>

<AppContainer/>

</Root>

</Provider>

);

创建状态触发事件业务集 ./store/reducers/counter.js :

let count = 0;

export default function (state = count, action) {

switch (action.type) {

case "Increment":

count++;

break;

case "Decrement":

count--;

break;

}

return count;

}

这里是根据触时不同条件要执行的业务,例如数字的增加和减少。假如项目下有很多触发业务集合,我们需要把他们归纳一起,并且方便获取状态值获取,新建 ./src/store/index.js :

import {combineReducers} from "redux";

import countReducer from "./reducers/counter";

const allReducers = combineReducers({

count: countReducer,

});

export default allReducers;

然后需要有个动作器来触发上面的业务,新建 ./src/store/actions/counter.js :

export function increment() {

return {

type: "Increment"

};

}

export function decrement() {

return {

type: "Decrement"

};

}

如果需要改动状态值只能从上面的函数进行触发,这是唯一入口。

下面就编写页面进行测试,新建 ./src/screens/reduxDemo/index.js :

import React, {Component} from "react";

import {Container, Content, Text, Card, Header, Body, Button, Title, CardItem} from "native-base";

import {increment, decrement} from "../../store/actions/counter";

import {bindActionCreators} from "redux";

import {connect} from "react-redux";

class Counter extends Component {

render() {

console.log(this.props.count);

return (

<Container>

<Header>

<Body>

<Title>Redux 计数器</Title>

</Body>

</Header>

<Content padder>

<Card>

<CardItem>

<Text>

{this.props.count}

</Text>

</CardItem>

</Card>

<Text/>

<Button block onPress={() => this.props.increment()}>

<Text>增加</Text>

</Button>

<Text/>

<Button block onPress={() => this.props.decrement()}>

<Text>减少</Text>

</Button>

</Content>

</Container>

);

}

}

function mapStateToProps(state) {

return {

count: state.count // 这里等效于 prop.state 不过redux1帮你封装好的

};

}

function matchDispatchToProps(dispatch) {

return bindActionCreators({increment: increment, decrement: decrement}, dispatch); // 绑定动作事件

}

export default connect(mapStateToProps, matchDispatchToProps)(Counter); // 连接Redux

以上是 React Native 添加 Redux 支持 的全部内容, 来源链接: utcz.com/z/381908.html

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