Single tab bar item present different view controllers depending on a condition?

Question

I am making an app that has a couple of different tabs using a tab bar controller. I add items to a bag in the first tab, and update the cart in the next viewcontroller. If the user goes to the second tab (the cart) without adding anything I want it to present a view controller saying the cart is empty. If they go to it once they have added something then it will show a table view.

Is there any way to tell a tab bar controller to present different view controllers depending on a condition?

score 3 · Accepted Answer · answered Dec 29 '16 at 18:08

The simplest option is to use one CartViewController, whose view has two subviews, a table view (A) with the cart items and another view (B) with the 'cart is empty' message.

Override its viewWillAppear function, and depending on the cart, show view A and hide view B or vice versa.

You can modify the child view controllers of a UITabBarController, via the viewControllers property. However, doing this by reacting on changes in the cart is complicated an not worth the trouble, IMHO.

Thanks that's what I ended up doing, I think it's the simplest solution as well. — jnwagstaff, Jan 02 '17 at 19:47

score 2 · Answer 2 · edited May 23 '17 at 10:30

You can actually present the same UITableViewController. In that UITableViewController you must be knowing whether you have data or not. If you have a data for UITableViewController then you will show the items in cart in UITableViewController else you can have empty message in the same UITableViewController. You can refer this post to show empty message on `UITableViewController?

If no Table View results, display "No Results" on screen .

Single tab bar item present different view controllers depending on a condition?

2 Answers2