react-imageloader

A React component for wrangling image loading

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react-imageloader
🚨 This project is not maintained! 🚨
We are no longer using this component in our day-to-day work, so unfortunately, we have neglected maintenance of it for quite some time. Among the reasons why we haven't been using this component are:
- It has some design flaws - We've been more focus on react-native
However, it may still work for you. If you are looking for something like this, but don't want to take on an unmaintained dependency, check out this fork.
See the support matrix below if you are determined to use this.
One of the hardest things to wrangle in the browser is loading. When images and other linked elements appear in the DOM, the browser makes decisions on when to load them that sometimes result in problems for a site and its users, such as FOUC, unexpected load ordering, and degraded performance when many loads are occurring.
This React component can improve the situation by allowing you to display content while waiting for the image to load, as well as by showing alternate content if the image fails to load.

Usage

import React from 'react';
import ImageLoader from 'react-imageloader';

function preloader() {
  return <img src="spinner.gif" />;
}

React.render((
  <ImageLoader
    src="/path/to/image.jpg"
    wrapper={React.createFactory('div')}
    preloader={preloader}>
    Image load failed!
  </ImageLoader>
), document.body);

Props

Name | Type | Description ------------|----------|------------ className | string | An optional class name for the wrapper component. imgProps | object | An optional object containing props for the underlying img component. onError | function | An optional handler for the error event. onLoad | function | An optional handler for the load event. preloader | function | An optional function that returns a React element to be shown while the image loads. src | string | The URL of the image to be loaded. style | object | An optional object containing styles for the wrapper component. wrapper | function | A function that takes a props argument and returns a React element to be used as the wrapper component. Defaults to React.createFactory('span').

Children

Children passed to ImageLoader will be rendered only if the image fails to load. Children are essentially alternate content to show when the image is missing or unavailable.
For example:
React.createClass({
  // This will only show if "notgonnaload.jpg" doesn't load.
  errorMessage() {
    return (
      <div>
        <h2>Something went wrong!</h2>
        <p>Not gonna load "notgonnaload.jpg". bummer.</p>
      </div>
    );
  },
  render() {
    return (
      <ImageLoader src="notgonnaload.jpg">
        {this.errorMessage()}
      </ImageLoader>
    );
  }
})

Design Decisions (mistakes?)

Since v2.0, loading is done 'off DOM' in a JavaScript Image() (instead of hidden in the DOM via a React <img />), so values passed to the onLoad and onError callbacks will be the browser native values, not React's synthesized values. While this shouldn't be a problem for the vast majority of use cases, it can cause weirdness when browser caching is disabled (i.e., images loading twice, preloaders disappearing before the image is ready).

Supported versions of React

React | ImageLoader -------------|------------ <0.13 | 1.x >=0.13, <15 | 2.x >=15 | 3.x