为什么当我向表视图添加插入行时，我的应用程序会崩溃?

I am trying to add a row with an insert control (green plus) to my table view when the user presses edit. So far, I've got the insert row to show, but if the user tries to scroll the table view while it is in edit mode, the app crashes with the following error:I am trying to add a row with an insert control