核心数据错误 1600 和 133020

Question

我想我要到此为止了。我正在开发一个执行和 api 调用然后将响应存储在 Core Data 中的应用程序。我在 iphone 开发方面也很n00b，所以如果我的问题可以使用更多信息，请告诉我。

似乎每当我运行应用程序并且第一次调用 API 时，它都可以正常工作，但是当它更新核心数据中已经存在的数据时，我收到错误 130020 或 1600。我查看了它们的内容是：

1600 - NSValidationRelationshipDeniedDeleteError 133020 - NSManagedObjectMergeError

根据我的阅读，当 deleteRule 设置为拒绝时可能会出现 1600，但我的每个关系删除规则在数据模型中都设置为无效。

而对于 133020，我完全不知道该怎么办。

要注意的另一件有趣的事情是，对于这些错误何时弹出似乎没有任何逻辑（我可以确定）。一次可能是 1600，一次是 133020，另一次可能是完全没有，对于同一序列中的同一操作。

如果有人能给我一些关于我可以查看的内容，甚至我可以如何尝试调试它的指示，我将不胜感激。

我粘贴了以下 2 段代码，它们似乎始终会导致至少一个错误：

- (void)updatePhotoAlbumsForGroup:(NSNumber *)gid notifyRegistrant:(id <APRegistrant>)registrant {
  NSManagedObjectContext *context = [[self newContextWithSharedCoordinator] autorelease];
  [self registerObserver:registrant selector:@selector(managedObjectContextDidSave:) forDidSaveNotificationFromContext:context];

  APGroup *group = [APCoreDataRequests fetchGroupWithGID:gid inContext:context];

  // Download and create new albums
  [self queueBlock:^{
    NSArray *drupalAlbums = [_drupalRequests getPhotoAlbumsForGroup:gid];
    if ([drupalAlbums count]) {
      [self refreshPhotoAlbumsForGroup:group withDrupalAlbums:drupalAlbums inContext:context];

      // Save any changes
      dispatch_async(dispatch_get_main_queue(), ^{
        [self saveContext:context];
      });
    }
  }];
}

这是上面调用的 refreshphotoalbumsforgroup 函数：

/**
 Uses the drupal albums to create new albums, update existing ones, and delete dead ones.
 */
- (void)refreshPhotoAlbumsForGroup:(APGroup *)group withDrupalAlbums:(NSArray *)drupalAlbums inContext:(NSManagedObjectContext *)context {
  NSMutableArray *newDrupalAlbums = [NSMutableArray arrayWithArray:drupalAlbums];
  NSMutableArray *existingAlbumsToDelete = [NSMutableArray array];

  // Update existing albums and collect albums to be deleted and created
  if (group.photoAlbums) {
    for (APPhotoAlbum *album in group.photoAlbums) {
      BOOL deleteAlbum = YES;

      for (NSDictionary *drupalAlbum in drupalAlbums) {
        NSNumber *aid = [drupalAlbum objectForKey:kGetPhotoAlbumsAIDKey];
        if (aid) {
          if ([aid isEqualToNumber:album.aid]) {
            deleteAlbum = NO;

            // Update existing album
            NSString *title = [drupalAlbum objectForKey:kGetPhotoAlbumsTitleKey];
            if (title) album.title = title;
            NSString *repPhotoURL = [drupalAlbum objectForKey:kGetPhotoAlbumsRepresentativePhotoURLKey];
            if (repPhotoURL) album.representativePhotoURL = repPhotoURL;
            NSNumber *numPhotos = [drupalAlbum objectForKey:kGetPhotoAlbumsNumberOfPhotosKey];
            if (numPhotos) album.numberOfPhotos = numPhotos;
            NSNumber *dateNum = [drupalAlbum objectForKey:kGetPhotoAlbumsModificationDateKey];
            if (dateNum) album.modificationDate = [NSDate dateWithTimeIntervalSince1970:[dateNum doubleValue]];
            NSNumber *radioactivity = [drupalAlbum objectForKey:kGetPhotoAlbumsRadioactivityKey];
            if (radioactivity) album.radioactivity = radioactivity;

            [newDrupalAlbums removeObject:drupalAlbum];
            break;
          }
        }
        else {
          [newDrupalAlbums removeObject:drupalAlbum];
        }
      }

      if (deleteAlbum) {
        [existingAlbumsToDelete addObject:album];
      }
    }
  }

  // Delete albums
  for (APPhotoAlbum *album in existingAlbumsToDelete) {
    [context deleteObject:album];
  }

  // Create and add new albums
  NSMutableSet *currentAlbums = [NSMutableSet setWithSet:group.photoAlbums];
  for (NSDictionary *drupalAlbum in newDrupalAlbums) {
    NSNumber *aid = [drupalAlbum objectForKey:kGetPhotoAlbumsAIDKey];
    APPhotoAlbum *album = [APCoreDataRequests fetchPhotoAlbumWithAID:aid inContext:context];

    // Set album properties
    NSString *title = [drupalAlbum objectForKey:kGetPhotoAlbumsTitleKey];
    if (title) album.title = title;
    NSString *repPhotoURL = [drupalAlbum objectForKey:kGetPhotoAlbumsRepresentativePhotoURLKey];
    if (repPhotoURL) album.representativePhotoURL = repPhotoURL;
    NSNumber *numPhotos = [drupalAlbum objectForKey:kGetPhotoAlbumsNumberOfPhotosKey];
    if (numPhotos) album.numberOfPhotos = numPhotos;
    NSNumber *dateNum = [drupalAlbum objectForKey:kGetPhotoAlbumsModificationDateKey];
    if (dateNum) album.modificationDate = [NSDate dateWithTimeIntervalSince1970:[dateNum doubleValue]];
    NSNumber *radioactivity = [drupalAlbum objectForKey:kGetPhotoAlbumsRadioactivityKey];
    if (radioactivity) album.radioactivity = radioactivity;

    [currentAlbums addObject:album];
  }
  group.photoAlbums = [NSSet setWithSet:currentAlbums];
}

Answer 1

尝试设置托管对象上下文的mergePolicy，例如到NSMergeByPropertyObjectTrumpMergePolicy。它默认为NSErrorMergePolicy，如果多个上下文编辑同一个对象，它总是会导致验证错误。