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Message-ID: <44266347.4060901@apache.org>
Date: Sun, 26 Mar 2006 11:47:51 +0200
From: Carsten Ziegeler <cziegeler@apache.org>
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To: Cocoon-Dev <dev@cocoon.apache.org>
Subject: CForms and Portlets - making form ids dynamic
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While cforms is excellent for developing form based applications, it has
some (minor) problems if Cocoon is used in a portal environment, being
it the Cocoon portal or Cocoon used as a JSR 168 portlet in a different
portal container.
One of the problems is the uniqueness of ids in the resulting html: each
form and input field gets an id based on it's definition in the model.
While this works perfectly in a standalone environment this might lead
to problems with portals: the portlet may be displayed more than once or
the generated ids might interfere with ids generated by other portlets.
Therefore a portal usually provides kind of a namespace for each
portlet. Fortunately, CForms based applications can make use of such
namespaces if you set the id of the form to this namespace. This will
then lead to unique ids as the id of the form is prefixed to each input
field (the mechanism is in fact more general).
The only drawback is that you have to specify this id in the model. And
this means that the model is dynamic as each portlet instance must have
an own model as each instance must have a different id for the form.
This works but of course the form model is never cached.

To make cforms more portal friendly I suggest to extend the form
creating a little bit by:
- adding a createInstance(String formId) method to the FormDefinition
- adding createForm(source, String formId) methods to the FormManager
- adding a Form(formDefinition, formId) method to form.js

WDYT? Or is there a better solution?

Carsten
-- 
Carsten Ziegeler - Open Source Group, S&N AG
http://www.s-und-n.de
http://www.osoco.org/weblogs/rael/