reactjs - Dynamically load images before render -


i've browsed lot of questions can't find correct answer this. have images folder, , want display specific image in there. don't know name of image displayed, it's returned restful api along many other details on object i'm displaying.

i considered few alternatives that:

  • load images no matter what, render ones need. found in few places, think it's pretty heavy, isn't it?
  • use webpack require file need on fly.

the second option seems best here. however, when do:

componentdidmount() {     axios.get('http://url.to/my/restful/api')        .then(res => {            this.setstate(res.data);        }); } render() {     var pic = require(`../images/${this.state.picture}`)     return (<img src={pic} alt="some name" />) );

react complains can't load undefined, because starts rendering before axios call gets done. alternative display loader while call being done, or preventing rendering in general. question rather: what's best practice here? should have loader on every page loading dynamic data? suppose i'm missing something, why i'm reaching out. how that? lot.

try following:

class imageloader extends component {     constructor() {         super();          this.data = {             data: null         };     }      componentdidmount() {         axios.get("http://url.to/my/restful/api").then(res => {             this.setstate({ data: res.data });         });     }      render() {         return this.state.data             ? <img                   src={require(`../images/${this.state.data.picture}`)}                   alt="some name"               />             : null;     } }

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