在单元格文本字段的textFieldShouldEndEditing方法中调用时，UICollectionView重新加载数据不起作用

I am using textfield in my custom cell. All the delegate methods of textfields are working fine. When the editing of textfield completes, I am saving changed data and updating datasource (i have checked and data is updated too) and then calling [collectionView reloadData] method but delegate methods of UICollectionView are not fired.I am using textfield in my custom cell. All the