Question

I have multiple elements I need to load before the user has control over the page (mostly images, videos, and audio). Currently, I’m loading them with the $.when() function, like this:

//all elements are hidden, except for a black background and
//a "loading" gif in the middle.

$.when($.ajax("video1.ogv"), $.ajax("video2.ogv"), $.ajax("videoN.ogv"))
.then(function () {
   //show the site with all the content preloaded...
});

Is there any way to create a loading bar that shows the progress (in percentage) of all the elements loading in the background? Like what happens in most flash sites with heavy media, for example: http://www.saizenmedia.com/nightwishsite/

Can it be done purely with jQuery or Javascript?

Thanks in advance!

Answer 1

You can use the Progress Bar from jQuery UI

Upon loading of each element simply change the value of the progress bar.

$.when($.ajax("video1.ogv"))
.then(function () {
    videoLoaded[1] = true;
    updateProgressBar();
});

$.when($.ajax("video2.ogv"))
.then(function () {
    videoLoaded[2] = true;
    updateProgressBar();
});

$.when($.ajax("video3.ogv"))
.then(function () {
    videoLoaded[3] = true;
    updateProgressBar();
});

var updateProgressBar = function() {
    // iterate though the videoLoaded array and find the percentage of completed tasks
    $("#progressbar").progressbar("value", percentage);
}