TSSS - Offline Webapps with HTML & JS
There is a lot of interest lately in using JS to
make web applications more interactive, even a new acronym: AJaX
So for those of you that have been asleep the
last few months, the basic gist is that you make a page with a bunch of
Javascript that fixes the differences between browsers to allow you to read and
write XML from a server and update the current page DOM. This is useful for
quickly updating the user interface without having to do a full page
refresh.Personally I think you can
skip this part of the talk and instead look at this article, in fact many of the
slides come from it:AJaX on
Apple's Developer SiteThe
example is quite simple, has everything in a single page i.e. no javascript
imports, and works on all the modern browsers. It doesn't talk about using XSLT
to transform the XML content, but many AJaX applications could use that as
well.Then they start getting into the
stuff that doesn't work everywhere. The newest version of ECMAScript
(JavaScript) includes support for XML as a native datatype. This is quite
powerful and was first implemented in WebLogic Workshop for doing XML data
transformations and then was submitted to
ECMA.One of the things that they don't
cover is that you now need a server implementation that can both render the
entire page and also allow incremental updates. If you wanted to do this all at
once I would probably build it such that the XMLHttpRequests grab sections of
the full render from the server using something like XQuery. I'm sure libraries
for doing this sort of thing will start to appear, perhaps even from me. The
maintenance of these features without merging the full render and the updates
seems prohibitive except for the most static
applications.The offline portion of
the talk was sort of a joke, suggesting that you download everything from the
website ahead of time and storing it in DOM. I was hoping they were going to
talk about technologies such as Apple's Dashboard that uses HTMl/CSS/JS to build
desktop applications.
Posted: Thu - March 3, 2005 at 11:45 AM
|