The Screen Navigation Framework is for customizing and extending application UIs. You can use it to make Liferay’s applications your own and to make your applications customizable by others.
To make this work, the framework assumes a specific structure for screens and
supports one or two levels of navigation. Each item in the top level navigation
ScreenNavigationCategory. Each item in the second level is
ScreenNavigationEntry. Categories are usually represented by tabs, while
entries use a second level of navigation. You need not have any Entries in your
application, but you must have at least one Category.
The Screen structure normally renders Navigation Categories as horizontal tabs at the top of the page and Navigation Entries as a vertical list of items along the left side of the page. The screen box containing the content uses the rest of the screen. You can customize this default layout for your needs.
Secondary navigation is optional; you may only need category tabs with no additional navigation.