presentviewcontroller ModalViewController on NavigationViewController error

ios7 i got this error

" Attemp to present <NavigationController> on <NavigationController> which is not on the window hierarchy"

I can fix this problem by presentviewcontroller directly to UIApplication's rootViewController

but this time it didn't appear whatever I did.

I found out the problem was navigationbarhidden

when navigationbarhidden is set to true

somehow on ios7 presentviewcontroller (modalviewcontroller) doesn't seem to work