foo.js

'use strict';

var lazy_load_image = require('../plugins/lazy-load-image.js');
var domready = require('detect-dom-ready');
var pubsub = require('pubsub-js');

// @TODO: This should only load images which are visible by default, not things that are inside hidden tabs etc
// @TODO: This loop probably belongs inside the plugin, not here
// @TODO: Select via data attributes instead of classes assuming IE8 supports this?
function process(element) {
  var images = element.getElementsByClassName('image');

  var count = images.length;
  for (var i=0; i < count; i++) {
    var instance = lazy_load_image(images[i]);
    instance.init();
  }
}

domready(function() {
  process(document);
});

pubsub.subscribe('domupdated', function(msg, element) {
  process(element);
});