 
         displayedMessagesRange.length += newMessagesCount
 
+        let needReloadLoadPreviousSection = self.needReloadLoadPreviousSection
+
         // 异常：两种计数不相等，治标：reload，避免插入
         if let messageIDs = messageIDs {
             if newMessagesCount != messageIDs.count {

                    indexPaths.append(indexPath)
                }

                conversationCollectionView.insertItemsAtIndexPaths(indexPaths)

                println("insert messages B")
            }

                    CATransaction.setDisableActions(true)

                    conversationCollectionView.performBatchUpdates({ [weak self] in
                        if needReloadLoadPreviousSection {
                            self?.conversationCollectionView.reloadSections(NSIndexSet(index: Section.LoadPrevious.rawValue))
                            self?.needReloadLoadPreviousSection = false
                        }
                        self?.conversationCollectionView.insertItemsAtIndexPaths(indexPaths)

                    }, completion: { [weak self] finished in
