Jquery Indexof Error For Xdomain.js Cross-domain Link Script

I'm using a script to detect cross-domain links for google analytics cross-domain tracking. The original script (xdomain.js) was provided by the great folks at Luna Metrics. Here

Solution 1:

Here you cache both the jQuerified element and the href attr.

var link = jQueryXD(this);
var href = link.attr('href');

Than why do you later do this:

jQueryXD(link).attr('href').indexOf(this)

You could either call link.attr('href').indexOf(this) since link is already a jQuery object or you could use directly the href you cached and do this href.indexOf(this).

Still I think the error you see happens when a link doesn't have an href attribute. So you better check if the href is not undefined before continuing your logic.

I tested it on both jQuery 1.2.6 and 1.7. It seems to be working fine.

Here's the finished script.

var jQueryXD = jQuery.noConflict();
/* I added var because page loads 2 versions 
    of jquery - not the source of the problem.*/functionlistenToClicks() {
    var domains = ["domain1.com", "domain2.com"];
    var fileTypes = [".pdf"];

    jQueryXD('a').each(function(index) {
        var link = jQueryXD(this);
        var href = link.attr('href');
        if(!href){
            // This element doesnt have a hrefreturntrue;
        }

        var valid = false;
        jQueryXD.each(fileTypes, function(i) {
            if (href.indexOf(this) != -1) { //this is line 40
                valid = false;
                link.bind('click', function(c) {
                    c.preventDefault();
                    _gat._getTrackerByName()._trackEvent('Download', 'Click - ' + link.attr('href'));
                    setTimeout('document.location = "' + href + '"', 100);
                });
            }
        });

        jQueryXD.each(domains, function(j) {
            try {
                if ((href.indexOf(this) != -1) && (window.location.href.indexOf(this) == -1)) {
                    valid = true;

                    if (valid) {
                        link.bind('click', function(l) {
                            if (typeof(_gat) == "object") {
                                l.preventDefault();
                                if (link.attr('target') != "_blank") { // _gaq.push(['_link',jQueryXD(link).attr('href')]);
                                    _gaq.push(['_link', href, true]); // mod
                                }
                                else {
                                    var tracker = _gat._getTrackerByName();
                                    //var fullUrl = tracker._getLinkerUrl(href);var fullUrl = tracker._getLinkerUrl(href, true); //modwindow.open(fullUrl);
                                }
                            }
                        });
                    }
                }

            }
            catch (e) {
                //Bad A tag
            }
        });

        var rootDomain = document.domain.split(".")[document.domain.split(".").length - 2] + "." + document.domain.split(".")[document.domain.split(".").length - 1];

        if ((href.match(/^http/)) && (href.indexOf(rootDomain) == -1) && !valid) {
            jQueryXD(link).bind('click', function(d) {
                d.preventDefault();
                _gat._getTrackerByName()._trackEvent('Outbound Link', href);
                setTimeout('document.location = "' + href + '"', 100);
            });
        }
    });

}

jQueryXD(document).ready(function() {
    listenToClicks();
});

But you might be reinventing the wheel here. There are some better scripts out there to achieve the same thing. I think you might be interested in looking into GAS. It's a wrapper around ga.js that extends and add a bunch of stuff including crossDomain and downloadTracking.

Spoiler: I'm the main developer of GAS.

https://github.com/CardinalPath/gas