redux

问题 I am new to js I am trying to use this.setState({ but I am getting a warning. can you guys tell me why I am getting the below warning warning.js:45 Warning: setState(...): Can only update a mounted or mounting component. This usually means you called setState() on an unmounted component. This is a no-op. Please check the code for the PerformanceChartNav component. Providing code below:- import React from 'react'; import {connect} from 'react-redux'; import moment from 'moment'; import height

问题 I'm working a codebase where it has lots of inconsistency as it has been worked on by multiple different person. function todos(state = [], action) { switch (action.type) { case 'ADD_TODO': return state.concat([ action.text ]) default: return state } } Instead of doing concat can I use spread syntax instead? return [...state, action.text] 回答1: Both, spread syntax and Array.prototype.concat() dont mutate the state, thus respecting the second rule of redux State is read-only 来源： https:/

问题 So I am new to react native and redux . The app is already configured (by someone else) to have react-navigation and redux . Now we're using a TabNavigator (bottom) for our menu and this TabNavigator also contains the Login button. Now what I want to do is when the user logs in, the Login button (with text and icon) becomes Logout. Is there a way to do that? Also my TabNavigator is in a separate file. What I want is something like this: TabNavigator( { ...other screens, //show this only if

问题 I have tabs which have three different components but I am trying to make it as two. I wanted to remove the basketball component and execute those functionalities inside Sports component itself Below line is used for creating tab content. So we cant delete pane component. {this.props.children} Basically what I am doing is wrapping my content with a div tag. So I am trying to do it directly on the calling component providing my code below https://jsfiddle.net/9e767txs/76/ class Basketball

问题 I am having a problem rendering the props value in react. I have added data fetched from an API to a redux store, and then mapped the state to my App component. The data shows up in my props when I view the component using react dev tools, and I can access the value of the API prop through the console by typing: $r.props.products.items[0].title Here's an image of Chrome dev tools illustrating ability to access props from App component for reference: But when I try to render the props in the

问题 I have a mapDispatchToProps function like this one below. export function mapDispatchToProps(dispatch, ownProps) { return { handleChangeLang: changeLocaleDispatcher(dispatch), handleChange: handleChangeDispatcher(dispatch), handleSubmit: handleSubmitDispatcher(dispatch) } } I just added redux-thunk to my project so I can access state from my action creators (think that's the correct term). It doesn't seem there's any documentation in redux-thunk outlining how to access getState from

问题 I am completely lost on the react-redux container (ie connector) concept as it is not doing what I anticipated. My issue is straight forward, and to me reasonable, yet I cannot find a well written example of how to accomplish it. Let us say we have a react component that connects to a store that has product context, and we will call this component ProductContext . Furthermore, let's say we want to reuse ProductContext liberally throughout the app so as to avoid the boilerplate code of

问题 How to customize nested components? I'm building React Native app with Redux. I have three screens in my app that render list of users. Follower/Following should show FollowButton : <FollowersContainer> <UserList onFollow={func} onUnfollow={func} users={[...]}> <UserCard user={user} onFollow={func} onUnfollow={func}> <FollowButton onFollow={func} onUnfollow={func} isFollowing={bool} userId={string} /> </UserCard> </UserList> </FollowersContainer> Ask question screen should show AskButton :

问题 So, I have the exact same problem as our friend here : How to render properties of objects in React? The below (upvoted) solution by Nahush Farkande : render() { let user = this.props.user || {}; .... {user.email} .... } works for me... if user is an object. However, in my specific case, the data I fetch and want to render is an array of objects. So, I return something like that : <ul> { user.map( (el, idx) => { return ( <li key = {idx}> <div className="panel-body clearfix"> {el.title} </div>

问题 We are implementing ngRedux for our Angular app. It all works nicely however I have on concern: memory usage, especially for mobile. Our stores state object looks like this: { leads : [], filters: [], applictionStatuses: [], } Let's say on of our user selects a datefilter in the list of leads which will grab 30.000 leads from our API (a whole year for example). As far as I understand redux, the state object will be cloned and then next object will look like { leads : [ {object}, {object} ...]