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

Backing up user data in Note to Self


So, with our new-found insight into exceptions, let's modify our Note to Self code and then we can be introduced to JSONObject and JSONException.

First, let's make some minor modifications to our Note class.

Add some more members that will act as the key in a key-value pair for each aspect of our Note class:

private static final String JSON_TITLE = "title";
private static final String JSON_DESCRIPTION = "description";
private static final String JSON_IDEA = "idea";
private static final String JSON_TODO = "todo";
private static final String JSON_IMPORTANT = "important";

Now, add a constructor and empty default constructor that receives a JSONObject and throws a JSONException. The body of the constructor initializes each of the members that define the properties of a single Note object by calling the getString or getBoolean method of the JSONObject, passing in the key as an argument. We also provide an empty default constructor, which is required now that we...