Question

I need your help,
I’m learning the coreData migration and I can’t access to the two models file inside my momd package.

I’ve done this :

In the init method for the two models:

urlModel2 =[[NSBundle mainBundle] URLForResource:@"DeptB" withExtension:@"mom"];

And in an other method :

NSManagedObjectModel* model2 = [[NSManagedObjectModel alloc] initWithContentsOfURL:[self urlModel2]];

I would like to have my two models in each NSManagedObjectModel to do a verification :

    NSMappingModel *mappingModel =
    [NSMappingModel inferredMappingModelForSourceModel:[self sourceModel]
                    destinationModel:[self destinationModel] error:outError];

you can found this at : http://developer.apple.com/library/ios/#documentation/Cocoa/Conceptual/CoreDataVersioning/Articles/vmLightweightMigration.html

Thank’s in advance !

Answer 1

I found the solution :

NSString* pathMOMD = [[NSBundle mainBundle] pathForResource:@"Dept" ofType:@"momd"];
NSBundle* bundleMOMD = [NSBundle bundleWithPath:pathMOMD];

// model 1
NSString* pathMOM = [bundleMOMD pathForResource:@"DeptB" ofType:@"mom"];
urlModel1 = [NSURL fileURLWithPath:pathMOM];
NSManagedObjectModel* model1 = [[NSManagedObjectModel alloc] initWithContentsOfURL:[self urlModel1]];
if(!model1){ NSLog(@"Problem for Model1"); }else{ NSLog(@"ok 1");}