react-瀑布流

import React,{Component} from 'react';
import {fetchData} from '../main';
class Pinterest extends Component{
    constructor(props){
        super(props);
        this.ajaxPull = this.ajaxPull.bind(this);
        this.state={
            leftData:[],
            centerData:[],
            rightData:[]
        };
        this.ajax = 1;

    };
    //@decorateArmour
    componentWillMount(){
        this.ajaxData();
    }
    componentDidMount(){
        document.addEventListener('scroll',this.ajaxPull)
    }
    componentWillUnmount(){
        document.removeEventListener('scroll',this.ajaxPull);
    }
    ajaxData=()=>{
        const {leftData,centerData,rightData}= this.state;
        this.ajax = 0;
        fetchData({reqUrl:'/zhanglei/common.json'}).then(result=>{
            this.ajax = 1;
            result.data.pull.content.map(item=>{
                const a = this.getMinContain();
                switch (a.className){
                    case 'u1':leftData.push(item);break;
                    case 'u2':centerData.push(item);break;
                    case 'u3':rightData.push(item);break;
                    default:return null;
                }
                this.setState({leftData,centerData,rightData});
            });
        });
    };
    //获取高度最低的一个
    getMinContain = () =>{
        const {newPinterest} = this;
        const {childNodes} = newPinterest;
        let minData = childNodes[0];
        childNodes&&childNodes.forEach(item=>{
            if(item.offsetHeight<minData.offsetHeight){
                minData = item
            }
        });
        return minData;
    };
    //滚动事件
    ajaxPull(){
        const height = window.innerHeight;
        const scroll = document.body.scrollTop;
        const domHeight = document.body.scrollHeight;
        if(scroll+height>domHeight - 132&&this.ajax){
            this.ajaxData();
        }
    };
    mapListToHtml=(data)=>{
        const arr = ['fadeIn','rotateIn','zoomIn'];
        const animate = parseInt(Math.random()*3);
        return data.map((item,index)=><li
            key={index}>
            <img style={{WebkitAnimation:`${arr[animate]} 0.8s ease-in-out 1 0s alternate forwards`}} src={`/img/${item.url}`} alt={item.name}/>
        </li>);
    };
    render(){
        const {leftData,centerData,rightData} = this.state;
        return (<div ref={ref=>this.newPinterest = ref} className="newPinterest clearfix">
            <ul ref={ref=>this.leftCol = ref} className="u1">
                {!!leftData&&this.mapListToHtml(leftData)}
            </ul>
            <ul ref={ref=>this.centerCol = ref} className="u2">
                {!!centerData&&this.mapListToHtml(centerData)}
            </ul>
            <ul ref={ref=>this.rightCol = ref} className="u3">
                {!!rightData&&this.mapListToHtml(rightData)}
            </ul>
        </div>)
    }
}
export default Pinterest;