renggli at iam.unibe.ch
Sat Apr 15 09:58:40 MEST 2006
I was just eating breakfast and wondering if it really makes sense to
define descriptions on the class-side. Sure this is a meta-thing, but
it is not something necessarily belonging to the class as we saw in
the mail of the original poster.
So it would probably make more sense to put descriptions describing
the instance to the instance-side, so that they can be easily created
depending on the current model state. The draw-back, there is usually
one, would be that retrieving the descriptions would be more
expensive as they cannot be cached anymore.
What do you think?
On 15 Apr 2006, at 09:23, Lukas Renggli wrote:
>> Has anyone done, or seen a sample of cascading dialog boxes done
>> with only magritte descriptions? Say I had a dropdown list of
>> classes, and when one was selected, I want the next drop down list
>> to contain methods in that class, or maybe countries and states, or
>> whatever. How can the second MultipleOptionDescription get it's
>> options: from the selector on the instance that the first
>> MultipleOptionDescription set the value on?
> Yes, however you need to specify the second description on the
> instance-side to be able to define it according to the state of your
> model. There are some examples on how to change descriptions on an
> instance-bases in the slides of my Magritte Tutorial (Dynamic
> Descriptions, 31-33) at <http://www.lukas-renggli.ch/smalltalk/
> Lukas Renggli
> SmallWiki, Magritte, Pier and Related Tools ...
More information about the SmallWiki