redux | 易学教程

How to dispatch an redux action to load data inside useEffect on page load

阅读更多关于 How to dispatch an redux action to load data inside useEffect on page load

问题 I am trying to integrate redux to an existing react application. I am learning redux. I am using hooks. In the internet there are many examples of using class components. I could not find an example how to achieve this with a function component. The code below does not throw an error. But, the action inside useEffect is not called. The code does not produce any output. I wonder if the call is correct or not. Any help? Index.js const store = createStore(rubricReducer, applyMiddleware(thunk));

Typing error “Default export of the module has or is using private name” - switch from typescript v1.8 to 2

阅读更多关于 Typing error “Default export of the module has or is using private name” - switch from typescript v1.8 to 2

问题 I've updated my ionic app from beta 11 to rc0. So it means I've switched from angular2 rc4 to angular2 stable and from typescript 1.8 to 2. I have a redux architecture and am using the Redux library. This line of code is giving me the following error export default combineReducers({ user,songs,app }) error TS4082: Default export of the module has or is using private name 'Reducer'. Any idea on what's going on and how to solve this? 回答1: The error went away when I made an explicit import of

Named exports with redux?

阅读更多关于 Named exports with redux?

问题 i have got used to using named exports as it makes life easier for refactoring. I have just started to implement redux but it seems i can't do a named export because the connect needs to map the component. so for example class Something extends Component { ... } export default connect(mapStateToProps)(Something); Would it be possible to use a named export like "Something", i can't place the export on the class as although react continues to work - the connect is not getting exported so there

Format date in Redux Reducer before it hits state

阅读更多关于 Format date in Redux Reducer before it hits state

问题 how can I format a date from a standard JS date object, which has come from the server and is fed into React via Redux through a REST api, which has an initial output of: "2016-05-16T13:07:00.000Z" Into a different format? So it is listed as DD MM YYYY ? Can I do this in the Reducer of Action by manipulating the request result, or the payload: import { FETCH_BOOKS, FETCH_BOOK } from '../actions'; const INITIAL_STATE = { books: [], book: null }; export default function(state = INITIAL_STATE,

Format date in Redux Reducer before it hits state

阅读更多关于 Format date in Redux Reducer before it hits state

Error withRef is removed. To access the wrapped instance, use a ref on the connected component when using Redux Form

阅读更多关于 Error withRef is removed. To access the wrapped instance, use a ref on the connected component when using Redux Form

问题 I am trying to get Redux Form to work for the first time and I am getting the following error: Invariant Violation withRef is removed. To access the wrapped instance, use a ref on the connected component. What am I doing wrong? The error is thrown as soon as I write (copy/paste from the example) the store. Here is the code. import React from "react"; import ReactDOM from "react-dom"; import { createStore, combineReducers } from 'redux' import { reducer as formReducer } from 'redux-form' const

你不知道的React 和 Vue 的20个区别

阅读更多关于你不知道的React 和 Vue 的20个区别

前言面试竞争力越来越大，是时候撸一波Vue和React源码啦；本文将前2个月面试总结成从20个层面来对比Vue和React的源码区别；文章有点长，可以收藏，慢点品尝；如果需要了解API的区别，请戳： Vue 开发必须知道的 36 个技巧 React 开发必须知道的 34 个技巧文章源码：请戳，原创码字不易，欢迎star！ 1.Vue和React源码区别 1.1 Vue源码来张Vue源码编译过程图图片来源：分析Vue源码实现 1.1.1 挂载初始化$mounted会挂载组件,不存在 render 函数时需要编译(compile); 1.1.2 compile 1.compile 分为 parse，optimize 和 generate，最终得到 render 函数； 2.parse 调用 parseHtml 方法，方法核心是利用正则解析 template 的指令，class 和 stype，得到 AST； 3.optimize 作用标记 static 静态节点，后面 patch,diff会跳过静态节点； 4.generate 是将 AST 转化为 render 函数表达式，执行 vm._render 方法将 render 表达式转化为VNode，得到 render 和 staticRenderFns 字符串； 5.vm._render 方法调用了 VNode

“Could not find router reducer” error when using connected-react-router

阅读更多关于 “Could not find router reducer” error when using connected-react-router

问题 I repeatedly get a Could not find router reducer in state tree, it must be mounted under "router" error when I do a dispatch(push("/")); call. index.tsx const store = configureStore(); ReactDOM.render( <Provider store={store}> <ConnectedRouter history={history}> <Switch> <Route exact path="/" component={HomeScreenContainer} /> <Route exact path="/login" component={LoginScreenContainer} /> </Switch> </ConnectedRouter> </Provider>, document.getElementById('root'), ); configureStore.ts export

Flutter状态管理Provider

阅读更多关于 Flutter状态管理Provider

学习Flutter一段时间了，偶然看到大家都说状态管理，多数人都是用redux，对于一个Android开发人员来说之前根本没接触过，于是开始了解 redux ，之后又了解闲鱼推出的 fish_redux ,然后又看到 Vadaski 发表的一系列关于Flutter状态管理的文章，包括 Scoped Model , Redux , BLoC , RxDart , provide （想了解的可以移步）,看的是眼花缭乱。对于Redux，能看懂是怎么写的，但真要到应用的层面，感觉还是有些吃力，更不知道怎样维护好它，一时间也不知道用什么什么适合自己。后来又接触到google推荐的Provider，于是学习了下。接下来就用Provider来实现一个计数的例子。第一步，添加Provider依赖 provider: ^2.0.1+1 pub地址： https://pub.dev/packages/provider 第二步，创建Model import 'package:provider/provider.dart'; class Counter with ChangeNotifier {//1 int _count; Counter(this._count); void add() { _count++; notifyListeners();//2 } get count => _count;/

Apollo Client Cache vs. Redux

阅读更多关于 Apollo Client Cache vs. Redux

问题 I'm trying to migrate from Redux Store to use Apollo Client Cache that comes with Apollo Graphql Client. One of the key features that sets Apollo Client apart from other data management solutions is its normalized cache . Just by setting up Apollo Client, you get an intelligent cache out of the box with no additional configuration required. With Redux we have to write actions, types and dispatch actions based on the response received from the side-effect and set the data in the store using