Software As She’s Developed

Day Barr:

Chat is not quite the Hello World of Ajax, but it’s one of the simplest yet useful things I could do. I didn’t learn very much by writing an Ajax Hello World example and it’s completely pointless

As many are learning, an Ajax “Hello World” is pretty easy, provided you’ve already got a grounding in web/JS programming. So beyond that, what’s the quintessential Ajax tutorial app? Some of the Ajax texts are beginning to pour out, so maybe a pattern will emerge. But, for now, the learning apps of choice seem to be:

• Chat. Using Periodic Refresh to show others’ responses (but that’s so last Tuesday … bonus points for persistent XMLHttpRequest connections.
• Auto-Completion Using Suggestions to complete the user’s query.
• Live Search Providing answers while the user types (Live Search), with a visible Progress Indicator during pauses.
• Slideshow Another popular category is the image slideshow, often using fancy visual effects for transitions.

I’m surprised we haven’t seen more people playing with Ajax wikis and RSS aggregators, but I’m sure they’re coming.

BTW, a basic “Hello World” might be easy, but it’s also a useful springboard for some important variants. e.g. Add a long delay in your server and see how the browser script handles a timeout (or simulate a delay with Julien’s GM script. e.g. Host the service on another domain and have the server act as a proxy. e.g. Apply a visual effect like the famous Yellow Fade Technique when the message comes in. These variants aren’t just interesting exercises - all are important for real-world Ajax development.