Ah, I see. How hard do you think it would it be to create a new
MAToManyDescription (or Container or whatever) subclass that worked
like this [1]? This seems like a common pattern so it might be a good
extension to the framework, and I don't think it would be very hard.
The component must already be calling add on a collection, so that add
call just needs to be selected by the subclass. Another option might
be to exchange the collection the memento uses now for a special
collection that overrides the #add and #remove methods. I'll take a
look at this today if I get a chance.
Thanks for the clarification. I hope you find time/interest in doing
more blog entries about doing things in Seaside/Magritte/Pier. :)
[1] Just to be totally clear for all, by "like this" I mean; have a
"read: whole collection", "modify: add to collection" and "modify:
remove from collection", instead of just "read: whole
collection"/"write: whole collection".
On 10/17/07, Ramon Leon <
[hidden email]> wrote:
> > In Ramon's blog [1] he mentions:
> >
> > "When creating a description for that collection, I can
> > specify my custom #accessor: rather than using the default
> > #selectorAccessor:
> > which then writes to my domain object with #addUser: and
> > #removeUser:."
> >
> > Looking at the code, I don't see how this is done. Isn't the
> > write accessor going to get a complete collection? Is the
> > idea to just diff the received collection from the one the
> > object had and make calls to #add and #remove as appropriate,
> > or is there a way to only be told about the new objects in
> > the collection?
> >
> > Thanks,
> > Jason
>
> That's exactly what I do. When I encapsulate a collection, I always provide
> the following
>
> #pluralCopyOfCollection
> #addX:
> #removeX:
>
> So...
>
> #people
> #addPerson:
> #removePerson:
>
> This doesn't work with Magritte expecting to be able to set the whole
> collection, so I use a custom accessor that removes items not contained in
> the new collection, and adds items not contained in the old collection. It
> requires a little reflection and a pluralize method to infer the collection
> name from the singular selector it's invoked with, i.e. #person for above
> sample.
>
> Ramon Leon
>
http://onsmalltalk.com>
>
> _______________________________________________
> SmallWiki, Magritte, Pier and Related Tools ...
>
https://www.iam.unibe.ch/mailman/listinfo/smallwiki>
_______________________________________________
SmallWiki, Magritte, Pier and Related Tools ...
https://www.iam.unibe.ch/mailman/listinfo/smallwiki
Locked
