I’m telling you, there is nothing better at work than to learn stuff. Good stuff.
For the longest time, I have been using listeners, with an understanding of the syntax, or how i’d use someone elses, but as to why i would really have one was finally completely illuminated (except for in the obvious case of JMS)–the crazy thing is–i’ve actually known this all along, but there was a connection in my head that wasn’t made between the problem domain and its solution. As my colleague was explaining it, it was like a plug finally went into a socket, and BOOM! aHA! i know precisely why I would want to use the Observer pattern, and, in fact, how to implement it.
The biggest gap in my head was, “how in the world do you actually just create a listener from scratch? am i writing a running program that sits and waits on events or something? that cannot be, because every listener i’ve come across is just an object; there’s nothing special going on…oh whatever i’ll just forget trying to figure it out for now”. Oh, the beauty of having actual other coders available in person to help illuminate this stuff to a brother.
After it was explained, it was so simple; i was a little ashamed for not picking up on it earlier. But dangit, all i had were books and web resources–the large majority I’ve found, only dealing with user interfaces. I don’t work with UIs much at all, I find myself trying to weed out what I need to be seeing and what I don’t. It was an immense help to actually have someone interactively write crap on paper to help illuminate it, particularly within the context of our problem domain. I went and downloaded the chapter on the Observer pattern again, and something that I previously would have read over and over and still no clickey, was immediately obvious to me. When i looked again at some UI code, it even made sense. :)