Android How to Program, 3/e

5.3 Technologies Overview

This section presents the new technologies that we use in the Doodlz app.

5.3.1 Activity and Fragment Lifecycle Methods

A Fragment’s lifecycle is tied to that of its parent Activity. There are six Activity lifecycle methods that have corresponding Fragment lifecycle methods—onCreate, onStart, onResume, onPause, onStop and onDestroy. When the system calls these methods on an Activity, it will also call the corresponding methods (and potentially other Fragment lifecycle methods) on all of the Activity’s attached Fragments.

This app uses Fragment lifecycle methods onResume and onPause. An Activity’s onResume method is called when a Fragment is on the screen and ready for the user to interact with it. When an Activity ...