Question

I have a blank <a> tag that content is loaded into via an external piece of javascript. I want to observe the <a> and when its content changes perform another task. The content will only ever change once.

Can this be done?

I am using also using jQuery.

Thanks in advance

Answer 1

You can use a mixture out of jQuery && DOM Level 3 events (see browser support below).

If you want to check for any changes within the content, you could do this:

var $a = $('a');

$a.one('DOMNodeInserted', function(e) {
    console.log('content changed!: ', e);    

    console.log('new content: ', $(this).html());   
});

$a.one('DOMAttrModified', function(e) {
    console.log('attribute changed!: ');        

    console.log('attribute that was changed: ', e.attrName);
});

See this code in action: http://jsfiddle.net/wJbMj/1/

Reference: DOMNodeInserted, DOMAttrModified

---

While the above solution is actually pretty convinient to me, it’ll only work in browser that support those events. To have a more generic solution, you can hook into jQuerys setter methods. The downside in this solution is, that you will only catch changes that were done through jQuery.

var _oldAttr = $.fn.attr;
$.fn.attr = function() {
    console.log('changed attr: ', arguments[0]);
    console.log('new value: ', arguments[1]);
    return _oldAttr.apply(this, arguments);
};

You could hook into .text() and .html() the exact same way. You would need to check if the this value within the overwritten methods represent the correct DOMnode.