react_img_loader.js

// Simple React Class for managing the loading state of an image asset
var ImgLoader = React.createClass({
    loadHandler: function () {
        this.setState({img_loaded: true});
    },
    getInitialState: function () {
        return {
            loading_src: 'https://dummyimage.com/700x700/ccc/ffffff.png&text=loading...',
            img_loaded: false
        }
    },
    componentDidMount() {
        var downloadingImage = new Image();
        downloadingImage.onload = this.loadHandler;
        downloadingImage.src = this.props.src;
    },

    render: function() {
        var src = this.state.loading_src;
        if (this.state.img_loaded) {
            src = this.props.src
        }
        return (<img src={ src } className="img-responsive"/>);
    }
});