我的核心数据出现了奇怪的错误。有时候，但是当我尝试访问核心数据对象时，我的应用程序崩溃的时间并非总是如此。
它经常出现在iPhone 3上，有时只出现在iPhone 4上。我查看了我的设备日志，并将其缩小到核心数据的问题。日志引用的行如下所示，tripInstructor是核心数据对象，它是AppManager类的属性。不确定这是否会产生很大的不同，但我确实声明该属性是“非原子的，保留”。
感谢您的任何建议
[self.supervisorLbl setText:[AppManager sharedAppManager].tripInstructor.name];
Date/Time: 2011-06-12 20:55:24.865 +1000
OS Version: iPhone OS 4.3.3 (8J2)
Report Version: 104
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x00000000, 0x00000000
Crashed Thread: 0
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libsystem_kernel.dylib 0x33e8da1c pthread_kill + 8
1 libsystem_c.dylib 0x35e5b3b4 pthread_kill + 52
2 libsystem_c.dylib 0x35e53bf8 abort + 72
3 libstdc++.6.dylib 0x33508a64 __gnu_cxx::__verbose_terminate_handler() + 376
4 libobjc.A.dylib 0x33f1106c _objc_terminate + 104
5 libstdc++.6.dylib 0x33506e36 _cxxabiv1::_terminate(void (*)()) + 46
6 libstdc++.6.dylib 0x33506e8a std::terminate() + 10
7 libstdc++.6.dylib 0x33506efe __cxa_rethrow + 62
8 libobjc.A.dylib 0x33f10fd8 objc_exception_rethrow + 4
9 CoreData 0x35624f66 _PFFaultHandlerLookupRow + 1450
10 CoreData 0x356799ba -[NSFaultHandler fulfillFault:withContext:] + 14
11 CoreData 0x35678782 _PF_FulfillDeferredFault + 354
12 CoreData 0x35623f18 _sharedIMPL_pvfk_core + 52
13 CoreData 0x35626b68 _pvfk_5 + 4
14 eLogger 0x0000e346 -[VicLogVC viewWillAppear:] (VicLogVC.m:207)
15 UIKit 0x3636bf14 -[UINavigationController _startTransition:fromViewController:toViewController:] + 604
16 UIKit 0x3636bc3c -[UINavigationController _startDeferredTransitionIfNeeded] + 176
17 UIKit 0x3635dd56 -[UINavigationController pushViewController:transition:forceImmediate:] + 634
18 UIKit 0x3635dacc -[UINavigationController pushViewController:animated:] + 28
19 eLogger 0x00025332 -[TripScreenVC _populateAndDisplayVicLog] (TripScreenVC.m:221)
20 eLogger 0x00025492 -[TripScreenVC _determineLogScreen] (TripScreenVC.m:258)
21 eLogger 0x000255d4 -[TripScreenVC buttonPressed:] (TripScreenVC.m:307)
22 CoreFoundation 0x30d4356a -[NSObject(NSObject) performSelector:withObject:withObject:] + 18
23 UIKit 0x36343ec2 -[UIApplication sendAction:to:from:forEvent:] + 78
24 UIKit 0x36343e62 -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 26
25 UIKit 0x36343e34 -[UIControl sendAction:to:forEvent:] + 32
26 UIKit 0x36343b86 -[UIControl(Internal) _sendActionsForEvents:withEvent:] + 350
27 UIKit 0x3634441c -[UIControl touchesEnded:withEvent:] + 336
28 UIKit 0x36342bee -[UIWindow _sendTouchesForEvent:] + 362
29 UIKit 0x36342568 -[UIWindow sendEvent:] + 256
30 UIKit 0x3632b30c -[UIApplication sendEvent:] + 292
31 UIKit 0x3632ac4c _UIApplicationHandleEvent + 5084
32 GraphicsServices 0x34e2be70 PurpleEventCallback + 660
33 CoreFoundation 0x30daaa90 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION + 20
34 CoreFoundation 0x30dac838 __CFRunLoopDoSource1 + 160
35 CoreFoundation 0x30dad606 __CFRunLoopRun + 514
36 CoreFoundation 0x30d3debc CFRunLoopRunSpecific + 224
37 CoreFoundation 0x30d3ddc4 CFRunLoopRunInMode + 52
38 GraphicsServices 0x34e2b418 GSEventRunModal + 108
39 GraphicsServices 0x34e2b4c4 GSEventRun + 56
40 UIKit 0x36355d62 -[UIApplication _run] + 398
41 UIKit 0x36353800 UIApplicationMain + 664
42 eLogger 0x00002ff8 main (main.m:14)
43 eLogger 0x00002fa0 start + 32
答案 0 :(得分：1)
您可能持有对托管对象的无效引用，看起来它被托管对象上下文变成了错误，可能是在上下文中调用-save：或-reset之后。
如果您从商店中删除了一个对象，并且仍然在ivar中保留了对托管对象的引用，那么这可能是导致此错误的原因。 CoreData会删除该对象，并在调用-save：时变为错误（此时您应该nil并重置您的ivars）。但是，当您尝试对对象进行故障时（通过访问其中一个或多个属性），在商店中找不到它，因为您删除了它。