Jon Udell writes about the use of Ajax technologies (Asynchronous JavaScript and XML) for powerful UIs:
et’s focus on how this technology can deliver the kinds of dashboard views that make hearts flutter in the enterprise. Until recently, I’ve used a couple of bookmarklets to gauge reaction to my InfoWorld articles, based on the list of del.icio.us bookmarks pointing to an article and the Bloglines summary of citations. Now, instead, I have a Greasemonkey script that counts these things and injects the counts into the InfoWorld pages I read.
You’d think these extra requests would slow things down. But because they’re asynchronous, they don’t. The script just fires off requests. When (or if) answers come back, it interpolates them into the page. Two components make this possible. One is the scriptable DOM, which enables in-situ alteration of Web pages. The other is the XMLHttpRequest object, which is now available in all the major browsers and which supports asynchronous interaction with remote services.
Combine the two and you get a powerful system for delivering real-time alerts in the context of Web pages. AJAX (Asynchronous JavaScript and XML) is the new name for this strategy, but it’s an old idea, and XML is optional. At its core, this is about Web pages that communicate autonomously and update themselves dynamically. You’ll soon see a lot more of these, and you may well find yourself creating some, too.
