jsx

问题 I am importing all SVG's from a folder in 'icons' through an index.jsx like the following line: index.jsx: export about from './about.svg'; Here goes the Import: Button.jsx import React from 'react'; import './MenuIcon.scss'; import * as IconID from './icons'; const Button = (props) => { return ( <div className="menu-icon" > <div className={'menu-icon__icon-wrapper'}> <IconID.about /> // This works great <IconID['about'] /> // This does not work </div> </div> ); }; export default Button; Now

问题 In React Native (I'm very new to React) I have a javascript function that returns an array in a variable called myResult. Printed in the terminal it shows: Array [ 25, 25, 20, 10, 5, 5, ] which I add to the state with this.setState({resultArray: myResult}); Then, in the state I have an array like so: this.state = { foodList: [ {id: "25", src: `"./images/banana25.png"` }, {id: "20", src: `"./images/banana20.png"` }, {id: "15", src: `"./images/apple15.png"` }, {id: "10", src: `"./images/mango10

问题 Let's say I have a component for lists rendering and I can do it in two different ways. The first one: const renderItem => item => <li>{item}</li>; const List = ({ items }) => ( <ul> {items.map(renderItem)} </ul> ); And the second one: const List = ({ items }) => { const renderItem => item => <li>{item}</li>; return ( <ul> {items.map(renderItem)} </ul> ); }; What is the difference between these approaches? I mean performance, renderings count, best practice or anti-pattern, etc. 回答1:

问题 In one of my .js file, I'm getting the following error from Webpack: 4 | export default function(ComposedComponent) { 5 | class Authentication extends Component { > 6 | static contextTypes = { | ^ 7 | router: React.PropTypes.object 8 | } 9 | These are my devdependencies: "devDependencies": { "babel-core": "^6.17.0", "babel-loader": "^6.2.0", "babel-plugin-transform-object-rest-spread": "^6.26.0", "babel-preset-env": "^1.6.0", "babel-preset-react": "^6.16.0", "babel-preset-stage-3": "^6.24.1",

问题 Note: I already looked into this question: Cant remove padding-bottom from Card Content in Material UI But the accepted answer did not fix my issue. I am using the Material UI React Library attempting to recreate the below image: I am completely new to using the Material UI, so most of my code will likely not be optimized and probably does not follow best practices. Indeed, I'd be interested to hear how it could be made better. Here is my code thus far: <Card className={classes.card}>

问题 I come from Angular and jquery before that. Seems that how state, props, contructors, ComponentDidMount etc.. are owning me. I simply have a Textarea that I want to end up json stringify the form data to on button click to set to the json, but i will even settle for just having the function set the textarea value. import React from 'react'; export default class ClinicalMain extends React.Component { constructor(props) { super(props); } state = { selectedOption : '' } // my function to update

问题 Followup from Return JSX from function I have a a component that needs to check for multiple options and return based on those options. Therefore I have created an outside function that is called in my component return statement to determine the format that will be returned: render() { const { policy } = this.props; let deployment = policy.Deployment; let value = policy.value; let policyLegend = deployment.policyLegend; let policyObj = this.valueToPolicy(policyLegend, value); console.log

问题 I'm fairly advanced in iOS Swift language, but very new in react native framework or javascript language. I also have tried to find the right tutorial for stack navigator for hours but I can't find it. I'm currently using this tutorial to learn the basic of react native stack navigation, and would like to split the two screens into their own files. Basically, I want to mimic Swift with its AppDelegate.swift and View Controller's files. But it generates error like this: Invariant Violation:

问题 I want to create React applications with JSX and not have to use a terminal or any server-side/dev environment commands. The environment we are using doesn't allow for commands to be run in the dev environment and these applications will be purely statically hosted on a CDN. So I know I can simply include Babel's browser.js to do the JSX transpiling in the browser. Perfect. My concern is that Babel apparently stopped supporting this and modern versions of Babel have it removed. Is there

问题 I am passing the date picked to the this.state.value Getting a time stamp of Midnight that day, but I can not seem to get it to render a new page so I can build the booking page. Where it takes the time stamp and checks for available times that day. When I did return the Handlesubmit on a half successful rerender I got a white page and back to the main app page with a blank date to choose again. I have tried to build this as a functional component in the handleSubmit But also tried to return