title: how to create pinterest style hiding/unhiding nav/tab bar?
body: <p>How do I create a hiding/unhiding nav bar like what pinterest and many other apps is doing? I know the basic idea is to use the UIScrollView delegate and detect whether I am scrolling up or down and show the nav bar based on that. So should I also adjust the navcontroller view height if the nav bar is hidden? How does this work?</p>