小编Buc*_*cky的帖子

我有一个方法执行NSFetchRequest以获取托管对象数组(特别是XMPPUserCoreDataStorageObjects).在performUserFetch返回数组之前对象是正确的,我可以打印所有的displayNames,但是一旦我将数组返回到printUserInfo,对象就会进入故障状态,除了Core Data不会带来问题他们回来了!

- (NSArray*)performUserFetch 
{
    NSManagedObjectContext *context = [[NSManagedObjectContext alloc] init];
    [context setPersistentStoreCoordinator:[xmppRosterStorage persistentStoreCoordinator]];
    [context setUndoManager:nil];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"XMPPUserCoreDataStorageObject" inManagedObjectContext:context];

    NSSortDescriptor *sd1 = [[NSSortDescriptor alloc] initWithKey:@"sectionNum" ascending:YES];
    NSSortDescriptor *sd2 = [[NSSortDescriptor alloc] initWithKey:@"displayName" ascending:YES];

    NSArray *sortDescriptors = [NSArray arrayWithObjects:sd1, sd2, nil];

    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    [fetchRequest setEntity:entity];
    [fetchRequest setSortDescriptors:sortDescriptors];
    [fetchRequest setReturnsObjectsAsFaults:NO];
    NSError *err;

    NSArray *result = [context executeFetchRequest:fetchRequest error:&err];
    return result;

}

- (void)printUserInfo 
{
    NSArray *result = [self performUserFetch];
    for(XMPPUserCoreDataStorageObject *user in result)
    {
        NSString …