React Native 添加 Redux 支持
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" } }
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 () => ( );
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 ({this.props.count} ); } } 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 Redux 计数器
总结
代码参考: RN-Demo