> It still seems that Struts is a few realeases away from anything
> like this. I guess I need to look at Barracuda again. Barracuda
> seems more applet-friendly, but I would guess that I am still out
> of luck.
Well, in terms of applets, I don't really think of either Struts or
Barracuda (or any other server-side technology) as being "non-applet
friendly"...you just write the applet, place it on the server, and reference
it in the browser markup and it will run in the browser (well, maybe, but
that's another issue).
Now, perhaps you're looking for something that's pre-written; that's
certainly a long-term goal within Barracuda. We'd like to have the developer
on the server just use a BTree component, and not have to worry about
whether its rendered as an applet or as javascript markup. Its not there yet
though.
Part of the problem is that there are so many different ways to simulate
tree controls in markup, and the particular approach you use will vary
depending on your particular requirements. Applets make the task a lot
easier, but there's all kinds of ancillary issues involved. I wrote
client-server apps for 2 years and we deployed them as applets...we were
able to do some pretty cool things, but the process was very painful because
of browser compatibility issues. From my perspective, the only hope for
applets is Java Plugin, and as much as I'd like to say that technology is
finally mature, I still don't think it is (although it has been a while
since I've looked at it, so maybe things have changed).
Keep in mind though, if Applets ever become viable, then the real question
becomes "Why write web-apps at all?" I think there will probably always be a
place for webapps, but its just so much easier to deliver advanced
functionality in the stated client-server paradigm. The thing that kills
applets is the JVM compatibility issues...
Anyway, I digress. The answer to your question is: Barracuda hopes to
address this at some point, but it's not there yet. Before you can abstract
something into a reusable component, you first have to figure out a reusable
process that works for the majority of scenarios, and for tree controls that
has proven elusive in the web-app paradigm.
Just my .02...
Christian
------------------------------------------------
Christian Cryder
[EMAIL PROTECTED]
Barracuda - Open-source MVC Component Framework for Webapps
http://barracuda.enhydra.org
------------------------------------------------
"What a great time to be a Geek"
>
> > -----Original Message-----
> > From: Dan Connelly [mailto:[EMAIL PROTECTED]]
> > Sent: Sunday, May 06, 2001 9:32 AM
> > To: [EMAIL PROTECTED]
> > Subject: Applets and Struts
> >
> >
> > Forgive me for being lazy about trying out applets with Struts.
> > I haven't "worked" it. Struts may be a few releases from
> > supporting applets in general. But my requirements are more
> > limited, as follows:
> >
> > I want to run a tree viewer applet with dynamic tree expansion
> > (and collapsing). "Dynamic" because the node expansion info will
> > gathered on the fly and fed to the live applet for display. This
> > is unlike DHTML techniques (like HierMenus) which are fully
> > populated in the JavaScript to begin with.
> >
> > There seem to be many such dynamic applets for trees about. They
> > are pretty cheap, pretty quick and pretty pretty. The "Tree
> > Navigation System" from Sirius Computer Consultants
> > www.jpowered.com is a good example, but any I'm not locked into
> > any particular component software.
> >
> > One of the advantages of a tree display, rather than a path walk,
> > is that you can see as much (or as little) of any sub-tree as you
> > want in one "page" display.
> >
> > In Struts you can use cascading sets of <html:select> option
> > lists to implement an "uncle" tree, a more limited form of tree
> > display. You see your uncles, but none of your cousins. At
> > least with the MVC in Struts you can navigate to an off-tree
> > action and then use the "Back" button to recover the current
> > state of the "uncle" tree.
> >
> > The Sirius Tree Navigation System doesn't support "Back". If
> > you go back, the tree has collapsed to its orignal, tight state.
> > This is not what I want. I want what Struts does, leave the
> > tree as it was before I navigated off-tree.
> >
> > So, I have these three criteria:
> > 1.. Dynamic "refresh" (from a shared database) each time a node
> > is expanded to sub-nodes.
> > 2.. Can see your cousins if you wish to.
> > 3.. Can use the "Back" button to recover the tree display after
> > following a link off-tree. (No dynamic update.)
> > How do I get there?
> >
> > I'm out of luck.
> >
> > It still seems that Struts is a few realeases away from anything
> > like this. I guess I need to look at Barracuda again. Barracuda
> > seems more applet-friendly, but I would guess that I am still out
> > of luck.
