On Jun 18, 2013, at 08:08 AM, Jerry Krinock <je...@ieee.org> wrote: > > On 2013 Jun 17, at 21:13, Martin Hewitson <martin.hewit...@aei.mpg.de> wrote: > >> I did try making a mapping model (this is something I've done in the past in >> other apps) but I got the same error message. > > Oh, well. > >> Is the idea that the auto-migration magic will pick up the mapping model and >> use it, if it finds it? > > Yes. I think the only three things you need do are to specify the current > version, and add .xcdatamodel and .xcmappingmodel files to your app target. > Xcode compiles the .xcdatamodel files into .mom files that all get put into a > .momd folder which also contains a VersionInfo.plist that specifies the > current version and the hashes for the entities in each version; also it > compiles each .xcmappingmodel files into a .cdm file. Finally, the .momd > folder and all the .cdm files get packaged into your product's Resources. > Given those pieces, it's a pretty easy reverse-engineering exercise to figure > out what the auto-migration magic must be doing.
According to your description, my app bundle's in good shape. I tried making a mapping model and the cdm file shows up in Resources, as expected. The momd folder contains all the expected mom and one omo file. > > Lately, Xcode has also been adding a .omo file, just one, named for the > current version, to the .momd. On Stack Overflow, 'Bobson' guessed that this > was "the same data [as the .mom file], organized differently". Probably not > a bad guess. Maybe optimized for faster access by Mountain Lion or something. Yes, I just noticed this ono file in the app bundle. I was wondering what that was... <snip> >> Then I go to open an existing document and I get the dreaded "migration >> failed, missing source managed object model" error. > > > After writing this message, you know I think it's more likely that you > screwed up and did this… > > • Change the data model a little. > • Create a document, "E". > • Get interrupted by a fire drill. > • Change the data model a little more. > • Build. > > In this case, indeed *no* version of your app will ever be able to open that > document "E". If this is your "existing" document, the "migration failed, > missing source managed object model" error is expected. I don't think this is the case since I can still drop back to version 11 and open the 'existing' document. I just made a test app and managed to perform a lightweight migration much like the one I'm trying here, so I guess I'm doing something wrong. I'll try to absorb your other detailed comments and see if I can get some more debug output to figure out what's going on. I just had another thought.... I have another core data model in the app. I wonder if the NSPersistentDocument infrastructure is picking up the wrong model? As I'm looking through the project, I realise I don't know how the document knows which core data model to use.... OK, back to the documentation on NSPersistentDocument. Thanks again, Martin _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
