MooTools Event Delegation
One feature I heard Moo developers hinting at was the future addition of event delegation to the MooTools JavaScript library. MooTools Core Developer, Aaron Newton, wrote a post today about a plugin he's created that does just that.
From the article:
Event delegation is a common practice where by you attach an event listener to a parent object to monitor its children rather than attach events to all the children. It's far more efficient when you have numerous items on a page that you want to interact with.
I don't know of any concrete plans to incorporate this functionality into MooTools 1.3 but I assume they will. I strongly suggest MooTools developers read Aaron's article at Clientcide. I also recommend this article for jQuery users as John Resig recently boasted of this addition to jQuery.
Exciting times in the framework world!
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John Resig, boasting!? GASP!
Thanks for the news David! … I’ve never been a fan of delegated events/event handlers – do they even bubble/propogate?
Let me add that event delegation is awesome when you’re continually adding DOM elements, perhaps via Ajax… I’m just not sure the performance benefits are as they seem.
@James: I didn’t mean “boasted” in a bad way. It’s an awesome addition which should be boasted. You can find the answer to your question here:
http://groups.google.com/group/mootools-users/browse_thread/thread/bbaf247948273868/db6a33205b71c89b?show_docid=db6a33205b71c89b
James, believe me with even a couple hundred elements you can see a big difference. It takes a few more elements to make a browser like Chrome slow up, but IE folks will see the difference on smaller numbers of events like night and day.