49. Working with the AppBar and Collapsing Toolbar Layouts
In this chapter we will be exploring the ways in which the app bar within an activity layout can be customized and made to react to the scrolling events taking place within other views on the screen. By making use of the CoordinatorLayout in conjunction with the AppBarLayout and CollapsingToolbarLayout containers, the app bar can be configured to display an image and to animate in and out of view. An upward scrolling motion on a list, for example, can be configured so that the app bar recedes from view and then reappears when a downward scrolling motion is performed.
Beginning with an overview of the elements that can comprise an app bar, this chapter will then work through a variety of examples of app bar configuration.