Book Image

Android Programming for Beginners - Second Edition

By : John Horton
Book Image

Android Programming for Beginners - Second Edition

By: John Horton

Overview of this book

Are you trying to start a career in programming, but haven't found the right way in? Do you have a great idea for an app, but don't know how to make it a reality? Or maybe you're just frustrated that in order to learn Android, you must know Java. If so, then this book is for you. This new and expanded second edition of Android Programming for Beginners will be your companion to create Android Pie applications from scratch. We will introduce you to all the fundamental concepts of programming in an Android context, from the basics of Java to working with the Android API. All examples use the up-to-date API classes, and are created from within Android Studio, the official Android development environment that helps supercharge your application development process. After this crash course, we'll dive deeper into Android programming and you'll learn how to create applications with a professional-standard UI through fragments and store your user's data with SQLite. In addition, you'll see how to make your apps multilingual, draw to the screen with a finger, and work with graphics, sound, and animations too. By the end of this book, you'll be ready to start building your own custom applications in Android and Java.
Table of Contents (35 chapters)
Android Programming for Beginners - Second Edition
Contributors
Preface
Other Books You May Enjoy
Index

Making the Note to Self settings persist


We have already learned how to save data to the device's memory. As we implement saving the user's settings, we will also see how we handle Switch input and where exactly the code we have just seen will go to make our app work the way we want it to.

Coding the SettingsActivity class

Most of the action will take place in the SettingsActivity.java file. So, click on the appropriate tab and we will add the code a bit at a time.

First, we need some member variables that will give us a working SharedPreferences and Editor reference. We also want a member variable to represent the user's settings option – whether they want decorative dividers or not.

Add the following member variables to SettingsActivity:

private SharedPreferences mPrefs;
private SharedPreferences.Editor mEditor;

private boolean mShowDividers;

Note

Import the SharedPreferences class:

import android.content.SharedPreferences;

Now, in onCreate, add the highlighted code to initialize mPrefs and mEditor...