DEPreLoad.js - DEMO

Include this in your page in <head>, or before </body>:

<script src="//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="jquery.DEPreLoad.js"></script>

Initialize the plugin within document ready function:

$(document).ready(function() {
    var loader = $("body").DEPreLoad({
        OnStep: function(percent) {},
        OnComplete: function() {}
    });
});