Question

I dont want to go through the data migration with an existing iphone app. Is is possible to have the ipad version use a different xcdatamodel file than the iphone version?

I search the project files where it reference myapp.xcdatamodel and cant find where it gets hooked up.

any suggestions?

Where is the appdelegate does it set this?

i do see:

NSURL *storeUrl = [NSURL fileURLWithPath: [[self applicationDocumentsDirectory] stringByAppendingPathComponent: @"storeLocations.sqlite"]];

Answer 1

There’s nothing magical about the persistent store coordinator or any other part of core data. They’re just objects with methods and properties, like anything else.

In your app delegate you just need to specify more than one, a la:

header

NSManagedObjectContext *managedObjectContext;
NSManagedObjectModel *managedObjectModel;
NSPersistentStoreCoordinator *persistentStoreCoordinator;

NSManagedObjectContext *managedObjectContext2;
NSManagedObjectModel *managedObjectModel2;
NSPersistentStoreCoordinator *persistentStoreCoordinator2;

implementation

- (NSManagedObjectContext *)managedObjectContext {

  if (managedObjectContext != nil) {
    return managedObjectContext;
  }

  NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
  if (coordinator != nil) {
    managedObjectContext = [[NSManagedObjectContext alloc] init];
    [managedObjectContext setPersistentStoreCoordinator:coordinator];
  }
  return managedObjectContext;
} 

and

- (NSManagedObjectContext *)managedObjectContext2 {

  if (managedObjectContext2 != nil) {
    return managedObjectContext2;
  }

  NSPersistentStoreCoordinator *coordinator2 = [self persistentStoreCoordinator2];
  if (coordinator2 != nil) {
    managedObjectContext2 = [[NSManagedObjectContext alloc] init];
    [managedObjectContext2 setPersistentStoreCoordinator:coordinator2];
  }
  return managedObjectContext2;
} 

etc.