cc'ing the list this time… On 2013-06-18, at 2:26 AM, Martin Hewitson <martin.hewit...@aei.mpg.de> wrote:
> > 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. > By default it will merge all models in the main bundle. So if the other model changed, you would also have a problem. If you want to specify only one model for the document, you should override [NSPersistentDocument managedObjectModel]. > 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/dave.fernandes%40utoronto.ca > > This email sent to dave.fernan...@utoronto.ca _______________________________________________ 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
