<div className={"break_down_div"}>
{this.state.breakDown && this.state.breakDown.length != 0?
<canvas className={"blueCircle"} ></canvas>
<div
ref={(elem) => { this.element = elem; }}
style = {divStyle}
className={`${this.props.styleSet}`}
>
</div>
:
}
</div> 
put canvas and div under one node
component class can only contain one top-level tag, otherwise it will report an error and wrap canvas and div in tags
import React from react ; import ReactDOM from react-dom ; import . assets styles index.less ; import Green from . assets images green.png ; import Red from . assets images red.png ; class Circle extends React.Component { constructor...
insert a large number of pictures into the project, how to simplify import React from react ; import ReactDOM from react-dom ; import . assets styles index.less ; import A0 from . assets images A0.png ; import A1 from . assets images A1.p...
...
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<div className={ video }> <div className={ allTasks fl } style = { this.state.current === 0 ? changeColor : changeColor02 ...
799 windy version of the infinite horizon of the empty mountain I m done here now. I don t know how to go on. I d like to ask you to help me write a simple demo . let values = item.split( ); let valuesContent = values.join(`keyWord`); I don...
componentWillMount() { const _self = this; var qs = (location.search.length>0?location.search.substring(1):""); var args = {}; var items = qs.length?qs.split("&"):[]; var item = null; ...
data.map(function(value, index){ console.log( valueTitle = , value.title) if( index< 6 ) { if( value.title === null || value.title === ) { value.title = } ...
const L1items = [{ title: , L2items:[ { title: , L3items:[ , ] } ] } let temp =new Object(_.find(L1items,(item)=>{ .... })); ...
renderFooter (quantity) { const _self = this; let wordStyle = { color: rgba(71,129,255,1) } let numberFrameCommon = { width: 40, height: 40, marginLeft: 10, ...
renderFooter2 (quantity) { const _self = this; console.log( showPageNumber = , _self.state.showPageNumber) let wordStyle = { color: rgba(71,129,255,1) } let numberFrameCommon = { wi...
componentWillReceiveProps =(newProps)=> { const _self = this; console.log( ); console.log( newProps = , newProps[ basicInformationData ]); let videoLength = 0; let videoSize = 0; let distanc...
I want to use Fetch to grab the data and return the captured data, but now I call the postFromServer function. I can t wait for Fetch, to return a undefined, directly. How can I solve this problem? module.exports = { postFromServer ( requestParam ...
recently added Wechat login function, the project is created through create-react-app, similar to 1 in the following figure, how should js be referenced? Can the sections of 2 and js be written directly into Component? ...
as shown in the figure, what does it mean to use @ plus the component name after introducing the component above? import React from react import ReactDom from react-dom import queryString from query-string import { connect } from react...
related codes index1.js export function getInitTime() { const nowTime = new Date(); const nowTimeStamp = new Date().getTime(); return { nowTime, nowTimeStamp } } index2.js import { getInitTime } from . index1 ; console.log(ge...
related codes index1.js export function getInitTime() { const nowTime = new Date(); const nowTimeStamp = new Date().getTime(); return { nowTime, nowTimeStamp } } index2.js import { getInitTime } from . index1 ; console.log(ge...
related codes index1.js export function getInitTime() { const nowTime = new Date(); const nowTimeStamp = new Date().getTime(); return { nowTime, nowTimeStamp } } index2.js import { getInitTime } from . index1 ; console.log(ge...
problem description case: there is a Form form in which the data is an obj object. When the attribute a satisfies the condition 1, it needs to be deleted. Is there any way not to affect whether the obj object still contains a attributes. let ob...
there is a solution for react performance optimization in "going deep into the React technology stack ". The original text is as follows (P106-P107 2.6 component performance optimization): as mentioned earlier, shouldComponentUpdate is the most comm...