How do I hide/show the right button in the Navigation Bar

Question

I need to hide the right button in the Navigation Bar, then unhide it after the user selects some options.

Unfortunately, the following doesn\'t work:

Answer 1

Show:

//set navigationItem tint color white
self.navigationItem.rightBarButtonItem.tintColor = [UIColor whiteColor];

Hide:

//set navigationItem tint clear white
self.navigationItem.rightBarButtonItem.tintColor = [UIColor clearColor];