Hi All,

I am trying to write an ultra simple solution to load a bunch of JS files asynchronously. I have the following script below so far. However the callback is sometimes called when the scripts aren't actually loaded which causes a variable not found error. If I refresh the page sometimes it just works because I guess the files are coming straight from the cache and thus are there quicker than the callback is called, it's very strange?

var Loader = function () {

}
Loader.prototype = {
    require: function (scripts, callback) {
        this.loadCount      = 0;
        this.totalRequired  = scripts.length;
        this.callback       = callback;

        for (var i = 0; i < scripts.length; i++) {
            this.writeScript(scripts[i]);
        }
    },
    loaded: function (evt) {
        this.loadCount++;

        if (this.loadCount == this.totalRequired && typeof this.callback == 'function') this.callback.call();
    },
    writeScript: function (src) {
        var self = this;
        var s = document.createElement('script');
        s.type = "text/javascript";
        s.async = true;
        s.src = src;
        s.addEventListener('load', function (e) { self.loaded(e); }, false);
        var head = document.getElementsByTagName('head')[0];
        head.appendChild(s);
    }
}

Is there anyway to test that a JS file is completely loaded, without putting something in the actual JS file it's self, because I would like to use the same pattern to load libraries out of my control (GMaps etc).

Invoking code, just before the tag.

var l = new Loader();
l.require([
    "ext2.js",
    "ext1.js"], 
    function() {
        var config = new MSW.Config();
        Refraction.Application().run(MSW.ViewMapper, config);
        console.log('All Scripts Loaded');
    });

Thanks for any help.