Hi Sophie,
sorry for the long delay...
try to give an intermediate answer as far as i can remember my
discussion with Uli...
sophie.ramel-bqDqoxiz9wg@xxxxxxxxxxxxxxxx wrote:
Hi Joern, Hi everyone,
You told me in a previous mail that you had thought of a solution about
optional elements;
I didn't work on it at all since some time, because since I wasn't in a
hurry anymore, I wanted to wait for chiba-sandbox to be complete.
So now I looked a little at the previous mails, and I think I understood
that we last said that we could at first use the "xforms:relevant"
attribute to do this (or implement an equivalent behavior in the engine)
+ find a way to render this correctly.
! lets remember the fact that i proposed the use of relevant as
*implementation* solution which doesn't solves the conceptual problem we
have - to handle Schema optional values correctly (right?)
So just to check if I remembered well, I tried to set the attribute
'xforms:relevant="string-length(.)>0"' on an exemple: the element
doesn't appear at all when the form is loaded, because non-relevant
nodes are not rendered... (which seems normal. And since we mustn't be
able to enter a value into a non-relevant node, I don't see how we could
do to use this...).
right, i think that's the correct analysis so far with one exception.
such a node *can* become relevant by the use of a setvalue action or
other modelitem properties e.g. a calculate="a+b" on the same bind element.
though the user may not input values directly this is not necessarily a
big drawback since actions can do it.
from my (and i hope i can speak for Uli too here) current view we had a
fundamental semantic misunderstanding of the meaning of the
xforms:relevant *and* the other bindings attributes:
a relevant is not a direct analogue for a Schema optional value, since
it deals with the relevance of the *value* of the node and *not* with
the relevance of the node itself.
the same is true for the other modelitem properties.
XForms validation/calculation builds is item-based and not structure
based - it simply cannot be used for that. this is resposibility of the
Schema validation facility (which btw is still one the most important
todos).
please excuse if i'm repeating obvious things. i think most of our
problems emerged cause we haven't separated things (what's Schema -
what's XForms) clearly enough.
Did you have time to think on a solution to this problem?
we should start over with a sample form. maybe we can extend a existing
one? then we can try to express your original requirements the 'pure'
way by separating what could be done in XForms and what's maybe have to
be done by Schema validation.
what do you think?
best,
Joern
best regards,
Sophie
PS: by the way, did you see
http://www.xml.com/pub/a/2003/09/10/xforms.html ?
-------------------------------------------------------
This sf.net email is sponsored by:ThinkGeek
Welcome to geek heaven.
http://thinkgeek.com/sf
|
