Need Suggestion for Add Button in Edit Mode of Table View

I have a tab bar app with a 开发者_StackOverflow社区nav bar and table view. In the nav bar, the left is the back button to the parent view, the middle has the view's title, and the right button is the edit button.

I need to somehow have a button to add cells to the view. There is obviously no room in the Nav bar so I was thinking that when the edit button is pressed, the first cell in the table should be a cell that is also an add button. When the done button (which is the edit button just its text has been toggled), the add button cell would disappear. What do you guys think is this a good way to do this or do you have any suggestions?

Also, how would I start to implement this feature? Thanks.

My be this post will help you.

Edit:

Take a look to this tutorial