Rename xcdatamodel file

Question

What do in need to do to rename the .xcdatamodel file. Renaming .xcdatamodel filename, along with changing ...

NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"newfilename" withExtension:@"momd"];
__managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];    
return __managedObjectModel;

and

NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"newfilename.sqlite"];

doesn't work! I get following error:

2011-04-11 17:19:54.164 ProjectName[5826:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Cannot create an NSPersistentStoreCoordinator with a nil model'
*** Call stack at first throw:
(
    0   CoreFoundation                      0x00fa15a9 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x010f5313 objc_exception_throw + 44
    2   CoreData                            0x00013853 -[NSPersistentStoreCoordinator initWithManagedObjectModel:] + 419
    3   ProjectName                         0x00003471 -[ProjectNameAppDelegate persistentStoreCoordinator] + 257
    4   ProjectName                         0x000031a4 -[ProjectNameAppDelegate managedObjectContext] + 100
    5   ProjectName                         0x000028ca -[ProjectNameAppDelegate makeSplitViewController] + 762
    6   ProjectName                         0x00002d44 -[ProjectNameAppDelegate application:didFinishLaunchingWithOptions:] + 68
    7   UIKit                               0x001f3c89 -[UIApplication _callInitializationDelegatesForURL:payload:suspended:] + 1163
    8   UIKit                               0x001f5d88 -[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:] + 439
    9   UIKit                               0x00200617 -[UIApplication handleEvent:withNewEvent:] + 1533
    10  UIKit                               0x001f8abf -[UIApplication sendEvent:] + 71
    11  UIKit                               0x001fdf2e _UIApplicationHandleEvent + 7576
    12  GraphicsServices                    0x018f9992 PurpleEventCallback + 1550
    13  CoreFoundation                      0x00f82944 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 52
    14  CoreFoundation                      0x00ee2cf7 __CFRunLoopDoSource1 + 215
    15  CoreFoundation                      0x00edff83 __CFRunLoopRun + 979
    16  CoreFoundation                      0x00edf840 CFRunLoopRunSpecific + 208
    17  CoreFoundation                      0x00edf761 CFRunLoopRunInMode + 97
    18  UIKit                               0x001f57d2 -[UIApplication _run] + 623
    19  UIKit                               0x00201c93 UIApplicationMain + 1160
    20  ProjectName                         0x00002599 main + 121
    21  ProjectName                         0x00002515 start + 53
)
terminate called after throwing an instance of 'NSException'

Note: I'm using Xcode4.

Answer 1

I have been having the same problem with Xcode 4. Don't know what the behaviour is in Xcode 3.

Firstly, when you add a core data model in xcode, you actually get a .xcdatamodeld file which is a package like the .xcodeproj file. In finder, you can right click it and "Show Package Contents". You'll see it contains a .xcdatamodel file.

It seems to me you can't rename it fully using xcode. Xcode will change the name of the package file (the momd) as you see it in the UI, but on the file system it has not actually changed.

The nil model error you get is because it can't find the newfilename momd since it still has the old name on disk. (I guess)

I worked around this by creating a new model with the name I wanted, then in the existing model, you can click-drag and select your entities, then just paste them into the new model file. You can then delete the old one and commit all the changes to your SCM.

Answer 2

Looks like momd missing in resources files. You can check in generated .app.

Make sure it is in compile sources build phase.

And clean/rebuild sometimes helps with xcdatamodels... Especially when creating/renaming them...

Answer 3

XCode 10 Update & Swift 4

Things may have changed a bit since XCode 4.2 It seems simplier in later versions because I just had to :

1. Change OLD.xcdatamodeld to NEW.xcdatamodeld in fileInspector left tab

2. In AppDelegate juste change the reference name : let container = NSPersistentContainer(name: "NEW")