title: core data: change objects in NSManagedObjectContextObjectsDidChangeNotification
body: <p>Is it possible to change attributes of managed objects in NSManagedObjectContextObjectsDidChangeNotification handler without firing the handler again?
  I get the data from our server and RestKit maps the data into Core Data. I have to change some attributes after the data arrives in my database.
  Thanks for help.</p>
  
  <p>Edit:
  This is my code. The <code>handleDidChangeNotification</code>method is called in a cycle:</p>
  
  <pre><code>- (void)addMyObserver
  {
      [[NSNotificationCenter defaultCenter] addObserver:self
                                               selector:@selector(handleDidChangeNotification:)
                                                   name:NSManagedObjectContextObjectsDidChangeNotification
                                                 object:self.objectManager.managedObjectStore.mainQueueManagedObjectContext];
  }
  
  - (void)handleDidChangeNotification:(NSNotification *)notification
  {
      NSSet *updatedObjects = [[notification userInfo] objectForKey:NSUpdatedObjectsKey];
      NSSet *deletedObjects = [[notification userInfo] objectForKey:NSDeletedObjectsKey];
      NSSet *insertedObjects = [[notification userInfo] objectForKey:NSInsertedObjectsKey];
  
      // modifiedObjects with store entity:
      NSSet *modifiedObjects = [updatedObjects setByAddingObjectsFromSet:insertedObjects];
      NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF isKindOfClass: %@", [MyStore class]];
      NSSet *modifiedStoreObjects = [modifiedObjects filteredSetUsingPredicate:predicate];
  
      if (modifiedStoreObjects.count &gt; 0)
      {
          [modifiedStoreObjects enumerateObjectsUsingBlock:^(MyStore *store, BOOL *stop)
           {
               store.distanceValue = 1000;
           }];
      }
  }
  </code></pre>