On Fri, Jul 30, 2010 at 2:11 PM, Martin Stanley
<[email protected]> wrote:
> 2- the invalid predicate breaks the NSPredicateEditor. My 
> NSPredicateEditorRowTemplate subclass populates its popup button dynamically 
> based on the current contents of an NSArrayController bound to the entity in 
> question (e.g., Project). When it tries to match the popup to this predicate 
> it complains because there is no longer an entry matching the deleted 
> object's name.
>
> However, following your last suggestion, I think the following should work:
> - when a SmartGroup is created, register an observer on its predicate 
> attribute.
> - then whenever the predicate is changed:
>        - parse the predicate to find all of the objects mentioned (by name), 
> and
>        - create a bi-directional reference between each object and this 
> SmartGroup object
> - then when attempting to delete the object (e.g. a Project) inform the user 
> and, if given the go-ahead, clean up all predicates which reference the 
> object before asking Core Data to delete the object.

I think you're going about this backwards. Your predicate should
already be modeled in the document (by a SmartGroup entity or a
collection of related entities) and the predicate editor's delegate
should be the controller responsible for converting between the
predicate editor's representation and your model representation. This
would be evidence of a good MVC design.

--Kyle Sluder
_______________________________________________

Cocoa-dev mailing list ([email protected])

Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com

Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com

This email sent to [email protected]

Reply via email to