How do I find out which DOM element has the focus?

Question

I would like to find out, in JavaScript, which element currently has focus. I\'ve been looking through the DOM and haven\'t found what I need, yet. Is there a way to do this

Answer 1

A little helper that I've used for these purposes in Mootools:

FocusTracker = {
    startFocusTracking: function() {
       this.store('hasFocus', false);
       this.addEvent('focus', function() { this.store('hasFocus', true); });
       this.addEvent('blur', function() { this.store('hasFocus', false); });
    },

    hasFocus: function() {
       return this.retrieve('hasFocus');
    }
}

Element.implement(FocusTracker);

This way you can check if element has focus with el.hasFocus() provided that startFocusTracking() has been called on the given element.