ios - CoreData 无法完成未修改对象发生的错误。

Question

我尝试使用 访问 NSManagedObject 的浮点值

float f = [managedObject.price floatValue];

并得到以下错误。我认为这个错误是当一个对象被删除并且你试图操纵它时引起的。我不更新也不删除原始对象的任何属性。是否有任何其他原因会发生此错误？

  2011-07-29 13:02:54.797 AEsir[3760:707] *** Terminating app due to uncaught exception 'NSObjectInaccessibleException', reason: 'CoreData could not fulfill a fault for '0x6095d20 <x-coredata://6483BA33-F9AD-436C-91CB-0EE6E07F2FBE/Venue/p7>''
    *** Call stack at first throw:
    (
        0   CoreFoundation                      0x35c6464f __exceptionPreprocess + 114
        1   libobjc.A.dylib                     0x31cb9c5d objc_exception_throw + 24
        2   CoreData                            0x30a51e99 _PFFaultHandlerLookupRow + 1244
        3   CoreData                            0x30aa69c1 -[NSFaultHandler fulfillFault:withContext:] + 20
        4   CoreData                            0x30aa5789 _PF_FulfillDeferredFault + 360
        5   CoreData                            0x30a50f1f _sharedIMPL_pvfk_core + 58
        6   CoreData                            0x30ab481b _pvfk_16 + 10
        7   AEsir                               0x0000b641 -[VenueListViewController transactionSucceeded:] + 240
        8   Foundation                          0x35f31183 _nsnote_callback + 142
        9   CoreFoundation                      0x35c3320f __CFXNotificationPost_old + 402
        10  CoreFoundation                      0x35bcdeeb _CFXNotificationPostNotification + 118
        11  Foundation                          0x35f2e5d3 -[NSNotificationCenter postNotificationName:object:userInfo:] + 70
        12  AEsir                               0x00036c67 -[CreditManager finishTransaction:wasSuccessful:] + 170
        13  AEsir                               0x00036d4b -[CreditManager completeTransaction:] + 106
        14  AEsir                               0x00036ffb -[CreditManager paymentQueue:updatedTransactions:] + 246
        15  StoreKit                            0x35970da9 __NotifyObserverAboutChanges + 44
        16  CoreFoundation                      0x35bcc3c5 CFArrayApplyFunction + 40
        17  StoreKit                            0x359727f1 -[SKPaymentQueue _notifyObserversAboutChanges:] + 92
        18  StoreKit                            0x35972351 -[SKPaymentQueue _processUpdates:trimUnmatched:] + 860
        19  StoreKit                            0x35971137 -[SKPaymentQueue _transactionUpdatedNotification:] + 98
        20  Foundation                          0x35f31183 _nsnote_callback + 142
        21  CoreFoundation                      0x35c3320f __CFXNotificationPost_old + 402
        22  CoreFoundation                      0x35bcdeeb _CFXNotificationPostNotification + 118
        23  Foundation                          0x35f2e5d3 -[NSNotificationCenter postNotificationName:object:userInfo:] + 70
        24  AppSupport                          0x35272455 -[CPDistributedNotificationCenter deliverNotification:userInfo:] + 44
        25  AppSupport                          0x35273781 _CPDNDeliverNotification + 204
        26  AppSupport                          0x352721d7 _XDeliverNotification + 122
        27  AppSupport                          0x35268dd7 migHelperRecievePortCallout + 138
        28  CoreFoundation                      0x35c3ba97 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 26
        29  CoreFoundation                      0x35c3d83f __CFRunLoopDoSource1 + 166
        30  CoreFoundation                      0x35c3e60d __CFRunLoopRun + 520
        31  CoreFoundation                      0x35bceec3 CFRunLoopRunSpecific + 230
        32  CoreFoundation                      0x35bcedcb CFRunLoopRunInMode + 58
        33  GraphicsServices                    0x30b5d41f GSEventRunModal + 114
        34  GraphicsServices                    0x30b5d4cb GSEventRun + 62
        35  UIKit                               0x30dd9d69 -[UIApplication _run] + 404
        36  UIKit                               0x30dd7807 UIApplicationMain + 670
        37  AEsir                               0x00008093 main + 70
        38  AEsir                               0x00002d8c start + 52
    )

Answer 1

如果持久存储发生某些事情，例如您从上下文使用的持久存储管理器中删除存储。

但是，很可能托管对象已被删除，但您在别处保留了对它的引用。