@Jonah: Try out the Bubbling Library, you won’t regret it.

@Tom: Precisely, this is the beauty of this model. There is not need to define an event to subscribe a listener, you only need the event/message identifier (an string), and in the other hand the components can fire/broadcast a message to reach all the listeners with the same identifier. The components don’t need to know if there is a listener or not, and the listener don’t care about the sender/emitter. The current implementation of the Bubbling Core is JSLint friendly, and there is not way to access the the list of listeners, or senders, and from my point of view, I think it’s not necessary. If you have a situation where you need to know the event names and counts, share it with us, to see how can be implemented using the decoupling model.

I was just thinking of ways to handle this, and my immediate thoughts were using macros and an external macro expansion tool to maintain the strings, or creating a simple tool to find Bubbling.on and Bubbling.fire and list the discovered event names and counts.

Do you recommend particular solutions?

A given search results or detail page might have as many as 10 distinct components, each one needing to respond to events to update the page when the user has clicked various controls or new Ajax data has returned. So, by using a subscription model where events are published and any components needing to subscribe can do so allowed us to develop pieces separately and to easily integrate them with the whole page.

In all, the source code for the site exceeded 10,000 lines of JS (which is not a good thing!), but even with this complexity we were able to keep each widget decoupled and have clearly defined interfaces and data contracts.

I’m curious to experiment with YUI more and when I do, I’ll definitely check out the BubblingLibrary.

Definitely a great pattern for complex javascript UI’s, and thoroughly described. Thanks for the good work!

Will let you add a payload to custom events as well.

Developing in this style really does free up a lot of headaches and makes multi-developer (and multi-component) javascript a lot clearer.