Book Image

Android 9 Development Cookbook - Third Edition

By : Rick Boyer
Book Image

Android 9 Development Cookbook - Third Edition

By: Rick Boyer

Overview of this book

The Android OS has the largest installation base of any operating system in the world. There has never been a better time to learn Android development to write your own applications, or to make your own contributions to the open source community! With this extensively updated cookbook, you'll find solutions for working with the user interfaces, multitouch gestures, location awareness, web services, and device features such as the phone, camera, and accelerometer. You also get useful steps on packaging your app for the Android Market. Each recipe provides a clear solution and sample code you can use in your project from the outset. Whether you are writing your first app or your hundredth, this is a book that you will come back to time and time again, with its many tips and tricks on the rich features of Android Pie.
Table of Contents (24 chapters)
Title Page
Copyright and Credits
Dedication
About Packt
Contributors
Preface
Index

Creating and using a Fragment


Android didn't always support Fragments. The early versions of Android were designed for phones when screens had relatively small displays. It wasn't until Android started being used on tablets that there was a need to split the screen into smaller sections. Android 3.0 introduced the Fragments class and the Fragment Manager.

Along with a new class, also came the Fragment Lifecycle. The Fragment Lifecycle is similar to the Activity Lifecycle introduced in Chapter 1, Activities, as most events parallel the Activity Lifecycle.

Here's a brief overview of the main callbacks:

  • onAttach(): It's called when the Fragment is associated with an Activity.
  • onCreate(): It's called when the Fragment is first created.
  • onCreateView(): It's called when the Fragment is about to be displayed for the first time.
  • onActivityCreated(): It's called when the associated Activity is created.
  • onStart(): It's called when the Fragment will become visible to the user.
  • onResume(): It's called just...