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

There is a hidden file called .xccurrentversion which should be in the same location as your whatever.xcdatamodeld file. Inside there is a reference to your model which needs to be updated with the new name.

In some cases, you'll have to remove the .xcdatamodeld file from the project and add it again to make it work.

Answer 2

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 3

Thanks to all of you for helping me finally nail this one down. Here's how I fixed this after renaming my project in Xcode 4.2:

1) Delete the reference to the *.xcdatamodeld file in your project. If it's like mine, an editor won't load when you select it. This tells me a link was broken in the rename.

2) Right-click on the .xcdoeproj file for your project and select 'Show Package Contents'.

3) Drag the *.xcdatamodeld file you find there back into your project. Done.

My app buil