The HorizontalPageIndicator
component is used to represent the currently
active page and total pages of an app.
Anatomy

A page indicator can be either linear or curved. You don't need to
specify whether your screen is round or rectangular.
HorizontalPageIndicator
changes depending on the screen
shape. It is made up of one active indicator and at least one inactive
indicator.
A. Inactive indicator
B. Active indicator
Use indicators to show users where they are in a carousel. Orient content from left to right.
Usage
See the following examples of how to use page indicators.