ios - Can't do ANYTHING with navigation bar -

i have structure:

when want add ´uinavigationitem´ storyboard navigation bar "disabled", tried add right button programatically:

uibarbuttonitem *button = [[uibarbuttonitem alloc]                            initwithbarbuttonsystemitem:uibarbuttonsystemitemadd                            target:self                            action:@selector(showpickerview:)]; self.navigationitem.rightbarbuttonitem = button; 

but nothing happens. renamed navigation bar title storyboard, when run app title not set. don't know source of problem. there button appearing. thank help.

each item in tab bar controller should have navigation controller root controller (well, don't need of them have nav controller if don't need them). have tab bar controller in navigation controller (unless it's modal) view controllers contained in tab bar controller can't see out navigation controller.