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After getting a better feel of XForms I have decided to roll my own form
pages rather than using an existing XML format. I initially didn't want
to create yet another xml to widget mapping, but nothing quite matches
what I need. I even took a look at
jelly-swing but there is way to much binding to the swing architecture
when you consider that a console mode and non-swing GUI are in the
initial design premise. So I am going to roll my own. Case and point,
how does one make a checkbox show up with XForms? You do either (a)
<input ... /> that is bound to an xsd:boolean value in the model, (b)
<select appearance='full'> with one <item/> child. Both are
counter-intuiotive to me and I would rather have one <checkbox />
element. I will use some ideas from XForms: like the nested label and
help elements though.
That was Problem #1. Problem #3 was roller eating my post because of
session expiration. But problem #2 is how to handle ant properites.
Anyone who has done much with a ant build.xml knows that the variables
ant users are set conter to the typical programming: the first setting
of the variable sticks and later sets are totally ignored. This actually
makes sense when put in context of a user-overridden values on the
command line. But when taken in context of a "back" button in a wizard a
first-set-win policy demolishes the concept of going back and changing
values. There are two tasks, ant and antcall, that break that rule, and
wizard will have to be another one. Overcoming the rules isn't that much
of a problem with the ant APIs.
The true problem comes in unsetting the properties, there is no
way via the APIs. You can get a Propeties object but that is just a
copy, not the local value. So you cannot un-set a value. But the if and
unless atributes go by whether the property is set or not set. I
considered making some of my elements sensitive to true/false values,
but the target would not be sensitive. This would make using properties
to drive the dependent component installs impossible, which was the
whole point to me of using ant to do the installs: to declaritively
determiine the needed dependencies. But it's not insurmountable. The
magic of introspection allows me to forcably introspect the values and
change them. For anyone who thinks that RTTI is wrong, add me to your
list of violaters.
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