Re: [Leopard] Core Data model versioning vs. NSPersistentDocument

FROM : mmalc crawford
DATE : Wed Nov 07 19:59:24 2007

On Nov 6, 2007, at 9:03 PM, mmalc crawford wrote:

> Hmm, no.  Generally NSPersistentDocument doesn't seem very happy 
> with the original implementation.  I've created an updated version 
> that uses a subclass of NSDocumentController to perform the 
> migration: <http://homepage.mac.com/mmalc/CocoaExamples/controllers.html

> >.  I still don't think it's ideal, but thus far it seems better 
> than the original.  I'll let you know if it changes significantly 
> again.
>

I've "played around" with this a little more.  It now does a fair 
amount of error checking etc. as well.  NSDocumentController does seem 
to be the easiest place to deal with this...  In particular, it now 
checks that you don't already have an existing file at the 
destination, an if you do (subject to user acceptance) it deletes it. 
Otherwise Core Data would simply append to the existing file.
Feedback would be welcome (please send off-list).

mmalc