I've been having some similar questions about datatable usage and
general web "patterns", specifically walking a database and linking to
detail pages with id values.
The detail of my questions are in my big post to javaranch...
http://saloon.javaranch.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic&f=82&t=000422
I worked with the O'Reilly book example, and that's where I originally
came up with my issue. If you use the standard dataTable, you have to
keep your values in session between the time you show the list and when
they click on the value. If you get the values from the db each time,
you open the possibility that the index will have changed, and the
selected value will be incorrect. If you keep the values in session,
its keeping a lot of data around, and you need to explicitly code a refresh.
I was pointed to the ext dataTable and the forceId (something something)
attribute, which allows you to specify and id. This does solve the
problem of inconsistancy. However, when the user submits, I assume you
have to get the full list and then scan for the selected value. Yes?
I'll look into the <t:saveState>, as I haven't looked at that yet.
Anyway, I was also looking for some input as to a suggested way of
handling this. In the above post, I outline how I've classically
handled this type of issue. I'm hoping to find some insight into the
best way to do that with JSF.
Thanks in advance,
-Kevin
CONNER, BRENDAN (SBCSI) wrote:
In answer to your second question, I believe you need <t:saveState> so
JSF will rebuild the table in its component tree upon submitting the
request, so you can access the values present in the previous request.
- Brendan
-----Original Message-----
*From:* Rick Reumann [mailto:[EMAIL PROTECTED]
*Sent:* Monday, August 29, 2005 9:22 AM
*To:* MyFaces Discussion
*Subject:* Concerning DataModel usage plus overhead?
I haven't really used the DataModel class yet, but as described by
Brendan in another thread, I have a couple of questions about the
concepts behind it...
First a simple example...
Want to display on a page a list of employees. User should be able
to click on employee and brought to an edit page to edit the employee.
My question in a previous thread was how to best accomplish this. I
figured a simple link passing in an ID would make the most sense,
but it seems like there was recommendations to use a dataModel. But
say my initial ist was...
Fred
John
Billy
Questions:
1) I want to click on one of those names and edit the user. This
initial collection of employees shouldn't contain the full employee
info - its just name and ID. It's way too much overhead to pull back
the full employee information at this stage, so all I have as a name
and an ID.
2) Why would I want to really save the state of this tableData in
this case using t:saveState since I really don't care about this
list anymore once the name is clicked. I'm going to be brought to a
totally new editEmployee screen and no longer need this collection
around. When I want the updated list I should get it from the
backend again.
Please someone help me understand how to best accomplish what I want
to do. It seems like such an easy concept but yet I haven't seen a
good explanation or an example (granted I don't have the O'Reilly
book, from what seems to be described I'm not certain that example
will be what I want either).
Thanks so much.
--
Rick
