UITabBarController, each functional area or tab is a root view. In effect, the tab bar controller is the real root view of the application, as you can see in Figure 7-10.
When the user taps an item in the tab bar, the root-level view for that item is shown, even if it is the currently selected tab bar item. For example, on your own device, open Music, select Playlists, select a playlist, and then tap the Playlists tab at the bottom. The app returns to the list of all playlists.
Figure 7-11 shows the parts of a tab bar controller. This tab bar, shown in white, has two items: the first with ...