UINavigationBar‘s manage a stack of UINavigationItems much like a UINavigationController manager a stack of UIViewControllers. To set what is visible directly, you should use either pushNavigationItem:animated: or setItems:animated: using the navigationItem of the view controller you want the bar to reflect.
eg:
self.navigationItem.title = @"A custom title";
[self.navigationBar pushNavigationItem:self.navigationItem animated:NO];
The above code where you have a property navigationBar which references the stand-alone navigation bar.
If you don’t want to manage it yourself, you can do as mplappert suggested and nest your view controller (without a stand-alone UINavigationBar) in a UINavigationController and present the navigation controller modally instead of your view controller.