目录
- 背景
- 设计理念
- 抽象代码结构
- 声明与定义
- 用法
- 高级用法
- 拆分/合并action
- API
- useSetState
- getAction
- polymerAction
- usePolymerActionState
- mergePolymerAction
背景
随着React Hooks 普及起来,组件逻辑写法变成函数式;逻辑函数声明、函数代码结构,随着逻辑增加复杂,代码组织混乱,函数声明散乱;
最关键的一点,每个人对代码理解不一样,有的喜欢在一个function 写大段逻辑,有的喜欢拆分逻辑很细,
就会使在项目维护时,代码风格、代码结构,越来越不统一,难以维护。
针对上述情况,需要可以组织代码结、梳理逻辑的方法,从而达到项目维护性高、代码结构统一、逻辑清晰
设计理念
抽象代码结构
在编写代码的过程中,发现可以抽象出公共代码结构;
- 声明可变数据/共享变量声明、state 声明/let xxx= xxx/useState
- 方法声明/function xx () {} /action/dispatch
- 方法调用 / xx() / action()/dispatch()
通过上图,可以把常见组件内部逻辑,分成3个部分,其中3、4属于相同部分:
:主要是声明数据,有useState/let xxx = 11;
:声明函数、方法,会涉及修改数据**setcounts**、使用数据**sendLogcount**;
其中修改与使用里会有一些辅助方法fetch来执行对应逻辑;
调用方法,3与4部分都在视图中使用函数与方法,统一称为调用方法。
把代码结构拆分、分析之后;其实在日常的开发过程中大部分代码复杂逻辑都在1与2部分,而2部分里有相互调用的逻辑,各种辅助函数相互杂糅在一起,慢慢的使得代码越来越复杂,难以阅读。
声明与定义
我们可以把1与2部分复杂封装起来,定义好规范干净的结构如
根据上图可知,把原先1、2、3 部分统一封装在一个hooks.js文件里;
- 原先1与2部分代码通过调用**polymerAction**给聚合起来,把state与actions/方法声明给放在一起;再通过**const [state, actions, shareVars] = usePolymerActionState(countActions)**对外暴露数据与acions/方法。
- 原先3部分封装hooks使用**usePolymerActionState**暴露方法调用,走正常调用逻辑。
- 在视图里,正常使用hooks 封装方法,**return**出**usePolymerActionState**暴露数据与方法,正常调用逻辑。
可以看出核心部分,就是把state与action封装在一起高内聚,通过对象组织代码结构,而对象可以进行组合方式,来组织更大复杂的代码逻辑与结构。
从视图上来看,只调用暴露出来的方法。
总结一下,按照上述方式,可以提高项目可维护性,代码结构统一。
用法
/** @jsx createElement */ import { createElement, useEffect, useState, useRef, useMemo } from 'react'; \ export default function Realtimetrendinghotels(props) { const { gdc, mds, pageUtils } = props; return (<CustomComponent />); }
import { createElement, useEffect, useState, useRef, useMemo } from 'react';` import {initHooksAction} from './hooks'; function CustomComponent(props) { const [ count, {setCounts, sendLog} ] = initHooksAction(); return ( <View style={{width: 100, height: 100, backgroundColor: 'red'}} onClick={() => { setCounts('参入数据了'); }}> <Text>{count}</Text> </View> ); }
initHooksAction可以拿到数据、方法;走正常逻辑;
const countActions = polymerAction({ count: 0 }, { setCounts({state, setState}, params) { setState({ count: ++state.count }) console.log(params) }, fetch({state, setState}, count) { console.log(`接口请求埋点${ count}`) }, sendLog({state, setState, actions}, count) { actions.fetch(count) console.log(`发送相关埋点${ count}`) }, }, {}); function initHooksAction() { const [state, actions, shareVars] = usePolymerActionState(countActions); useEffect(() => { sendLog(state.count); }, [state.count]) return [state.count, actions, shareVars] }
polymerAction:声明state、actions、shareVar;
usePolymerActionState:底层会重写actions方法,shareVar数据,
返回数据是对应polymerAction里声明的数据、方法
initHooksAction:封装hooks 逻辑
高级用法
拆分/合并action
const infiniteScrollAction = polymerAction({ isLoadingShow: false, isLoadingError: false, isEmptyData: false, }, { showLoading({ state, setState, shareVars, actions }) { setState({ isLoadingShow: true, isLoadingError: false, isEmptyData: false }); }, closeLoading({ state, setState, shareVars, actions }) { setState({ isLoadingShow: false }); shareVars.throttleTarget = true; }, ..., }, { throttleTarget: true, }); const handleAction = polymerAction({},{ /** * 刷新接口 */ onRefreshList({ state, setState, shareVars, actions }) { .... }, },{}) const scrollListAction = polymerAction({ cityList: [], recommendList: [], isCityListShow: false, }, { initListParam({ state, setState, shareVars, actions }) { shareVars.pageNo = 0; shareVars.dataVersion = 0; }, exp({ state, setState, shareVars, actions }, data) { const {cityName, cityCode} = shareVars.cityData; let shidsArr = []; if (data[0] && data[0].hotHotelList) { shidsArr = hotCityListShids(data); sendUT.exp(cityName, shidsArr[0].join('/'), shidsArr[1].join('/')); } else { shidsArr = shids(data); sendUT.exp(cityName, '', shidsArr.join('/')); } }, ..., }, { pageNo: 0, dataVersion: 0, cityData: { cityName: '', cityCode: '', } }); function initEffect(param) { const [state, action] = usePolymerActionState(mergePolymerAction(scrollListAction,infiniteScrollAction,handleAction)); ... ... return [state, action] }
通过**mergePolymerAction**可以把多个action,scrollListAction、infiniteScrollAction 、handleAction合并;这样就可以任意拆分action。
API
useSetState
管理 object 类型 state 的 Hooks,用法与 class 组件的 this.setState 基本一致。
const [state,setState] = useSetState({ hehe:1, aaa:1 }); // 修改 setState({ aaa:2 })
getAction
从polymerAction里,获取actions
const handleAction = polymerAction({},{ /** * 刷新接口 */ onRefreshList({ state, setState, shareVars, actions }) { .... }, },{}); const handle = getAction(handleAction); console.log(handle); ,{ /** * 刷新接口 */ onRefreshList({ state, setState, shareVars, actions }) { .... }, }
polymerAction
生成action 集合
const scrollListAction = polymerAction({ cityList: [], recommendList: [], isCityListShow: false, }, { initListParam({ state, setState, shareVars, actions }) { shareVars.pageNo = 0; shareVars.dataVersion = 0; }, ..., }, { pageNo: 0, dataVersion: 0, cityData: { cityName: '', cityCode: '', } });
const [state,actions,shareVal] = polymerAction(stateObj,actionObj,shareValObj)
Params
Result
actionObj
const handleAction = polymerAction({},{ /** * 刷新接口 */ onRefreshList({ state, actions,shareVars,setState,setShareVars },param) { ... }, /** * 接口报错,刷新接口 */ onRefreshListError({ state, setState, shareVars, actions }) { actions.getList(true); }, },{});
usePolymerActionState
根据传入action,转换成能改变页面的**PolymerActionState**
function initEffect(param) { const [state, actions] = usePolymerActionState(scrollListAction); ... ... return [state, action] }
const [state, actions,shareVal] = usePolymerActionState(polymerAction);
Params
Result
mergePolymerAction
合并多个 **polymerAction**
mergePolymerAction(scrollListAction,infiniteScrollAction,handleAction)
代码
let useState = null; let useRef = null; let useMemo = null; function useSetState(initData) { const [state, setState] = useState(initData); const dispatch = (next) => { if ( typeof next === 'object' ) { setState((pre) => Object.assign({}, pre, next)); } else { setState(next); } }; return [state, dispatch]; } function polymerAction(state, action = {}, shareVar = {}) { return [state, action, shareVar]; } function newActionData(actions, states, shareVars, setState) { let newAction = {}; Object.keys(actions) .forEach((name) => { const old = actions[name]; if ( typeof old === 'function' ) { // 重新写actions 方法 newAction[name] = function(...arg) { return old.call(null, { state: states, shareVars, actions: newAction, setState(param, fn = () => {}) { setState(param); fn(param); }, setShareVars(param) { shareVars = Object.assign(shareVars, param); }, }, ...arg); }; } }); return newAction; } // 与hooks 关联 function usePolymerActionState(param) { const [state, action = {}, shareVar = {}] = param; const actions = action; // Object.assign({}, xxx) 多个加载重复组件生成对应数据,防止数据相互覆盖情况 const [states, setState] = useSetState(Object.assign({}, state)); // 生成新共享变量 const shareVars = useMemo(() => (Object.assign({}, shareVar)), []) ; shareVars.updateAfterState = states; const newAction = useMemo(() => (newActionData(actions, states, shareVars, setState)), [action, states, shareVars]) return [states, newAction, shareVars]; } function getAction(polymer) { return polymer[1]; } function mergePolymerAction(action1, ...res) { const actions = action1.map(function (val, index) { let resAction = {}; res.forEach((action) => { Object.assign(resAction, action[index]); }); return Object.assign({}, val, resAction); }); return actions; } function injectState(newUseState, newUseRef, newUseMemo) { if (!newUseState || !newUseMemo) { console.warn(`请在模块中的moduleInit传入useState、useMemo, 如: moduleInit({ gdc,mds,pageUtils}) (useState, useEffect, useRef, useMemo);`); return } useState = newUseState; useRef = newUseRef; useMemo = newUseMemo; } export { useSetState, getAction, polymerAction, usePolymerActionState, mergePolymerAction, injectState };
github https://github.com/NoahsDante...
以上就是React Hooks之usePolymerAction抽象代码结构设计理念的详细内容,更多关于React Hooks usePolymerAction的资料请关注易盾网络其它相关文章!