Book Image

Android Studio 4.1 Development Essentials – Java Edition

By : Neil Smyth
Book Image

Android Studio 4.1 Development Essentials – Java Edition

By: Neil Smyth

Overview of this book

For developers, Android 11 has a ton of new capabilities. The goal of this book is to teach the skills necessary to develop Android-based applications using the Java programming language. This book begins with the steps necessary to set up an Android development and testing environment. An overview of Android Studio along with the architecture of Android is covered next, followed by an in-depth look at the design of Android applications and user interfaces using the Android Studio environment. You will also learn about the Android architecture components along with some advanced topics such as touch screen handling, gesture recognition, the recording and playback of audio, app links, dynamic delivery, the AndroidStudio profiler, Gradle build configuration, and submitting apps to the Google Play Developer Console. The concepts of material design, including the use of floating action buttons, Snackbars, tabbed interfaces, card views, navigation drawers, and collapsing toolbars are a highlight of this book. This edition of the book also covers printing, transitions, and cloud-based file storage; the foldable device support is the cherry on the cake. By the end of this course, you will be able to develop Android 11 Apps using Android Studio 4.1, Java, and Android Jetpack. The code files for the book can be found here: https://www.ebookfrenzy.com/retail/androidstudio41/index.php
Table of Contents (88 chapters)
88
Index

39.5 Creating a Lifecycle Owner

The final task in this chapter is to create a custom lifecycle owner class and demonstrate how to trigger events and modify the lifecycle state from within that class.

Add a new class by right-clicking on the app -> java -> com.ebookfrenzy.lifecycledemo entry in the Project tool window and selecting the New -> Java Class... menu option. Name the class DemoOwner in the Create Class dialog before tapping the keyboard Return key. With the new DemoOwner.java file loaded into the code editor, modify it as follows:

package com.ebookfrenzy.lifecycledemo;

 

import androidx.lifecycle.Lifecycle;

import androidx.lifecycle.LifecycleOwner;

import androidx.lifecycle.LifecycleRegistry;

 

import org.jetbrains.annotations.NotNull;

 

public class DemoOwner implements LifecycleOwner {

}

The class is going to need a LifecycleRegistry instance initialized with a reference to itself, and a getLifecycle() method configured...