Thomas Lutz wrote:
Hi list !
A recent discussion on the users list [1] showed that there is
interest in implementing a minimum/maximum number of rows check in
CForm's repeaters.
Jorg Heymans submitted a patch to bugzilla [2], that adds the
minimum-size and maximum-size attributes to the repeaters definition,
and contains a sample on disabling the controls with jx macros...
To complete this feature validation should be added. So, if the
current size is lower or greater than the specified values, a
validation message should be displayed, and the add-row or remove-row
buttons should be disabled.
Now the question for the CForm gurus :-):
What's the best way to do it ?
We've found two scenarios so far:
-try to add the validation in the validate function of Repeater.java
and disable the controls in Repeater.java
-write a validator class (like the ones described in [3]), set a flag,
and leave enabling/disabling of the controls to the presentation layer
(the forms-field-styling.xsl, or jx macros..?)
I'll try to implement it, but some advice where to start, and what to
touch would really be great, as am I still a CForms greenhorn :-).
Hmm... There are different issues here:
Validation:
We can extend the <fd:range> or <fd:value-count> validators so that they
can validate a repeater. But the issue then is that a repeater has no
way to automatically display its error, and therefore it's up the
template writer not to forget to add a <ft:validation-error> somewhere.
Enabling/disabling controls:
This is different from validation, as the controls must be disabled to
ensure that we don't go outside of the specified constraints. This
cannot be implemented as a validator (which is called too late in the
process), and requires the concept of min and max rows to be built into
the repeater itself.
I would go for this second solution, as it provides a better user
experience (you can't do the action, rather than having to correct it
afterwards), but this requires some changes to the repeater code:
- add min-rows/max-rows properties
- add support for repeater listeners, so that repeater-actions and
row-actions can register themselves on the repeater and automatically
change their state according to the size of the repeater.
Sylvain
--
Sylvain Wallez Anyware Technologies
http://people.apache.org/~sylvain http://www.anyware-tech.com
Apache Software Foundation Member Research & Technology Director
