Beginning Android® Programming with Android Studio
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To my children Christian, Sophia, and Giovanni;
Katie, Sarah, and Joe; and my love Jennifer.
J. F. DIMARZIO began developing computer programs—specifically games—in 1984 as a wide-eyed, curious child of the Atari age. Starting on the TRS-80 Color Computer II, in BASIC, he wrote several small text-based games and simple inventory applications. After leaving the Music program at the University of Massachusetts, J. F. moved into professional computer development; working for the United States Department of Defense, Walt Disney Imagineering, TechData, and The Walt Disney Company. In 2008, he started developing apps on the newly introduced Android platform (then on version 0.8). He has had 14 books published to date, 7 of which are on Android and Android game development.
CHÁD (SHOD) DARBY is an author, instructor, and speaker in the Java development world. As a recognized authority on Java applications and architectures, he has presented technical sessions at software development conferences worldwide (in the U.S., U.K., India, Italy, Russia, Netherlands, Singapore, Japan, and Australia). In his 20 years as a professional software architect, he's had the opportunity to work for Blue Cross/Blue Shield, Merck, Boeing, Red Hat, and a handful of startup companies.
Chád is a contributing author to several Java books, including Professional Java E-Commerce (Wrox Press), Beginning Java Networking (Wrox Press), and XML and Web Services Unleashed (Sams Publishing). Chád has Java certifications from Oracle and IBM. He holds a B.S. in Computer Science from Carnegie Mellon University.
J. F. DIMARZIO would like to thank Charlotte Kughen, Jim Minatel, Rick Kughen, and the team at John Wiley & Sons publishing; and Stacey Czarnowski, Katrina Bevan, and the team at Studio B.
I first started playing with the Android Software Development Kit (SDK) before it was officially released as version 0.8. Back then, the tools were unpolished, the application programming interfaces (APIs) in the SDK were unstable, and the documentation was sparse. Android is now one of the most popular mobile operating systems in the world.
Every day, more developers are trying Android development using Android Studio, either as a hobby or professionally. The current challenge for many beginning developers who want to move into the exciting world of android development is trying to determine where to start.
It was with this challenge in mind that I was motivated to write this book, one that could benefit beginning Android programmers and enable them to write progressively more sophisticated applications.
This book is written to help jump-start beginning Android developers, covering the necessary topics in a linear manner so that you can build on your knowledge without being overwhelmed by the details. I adopt the philosophy that the best way to learn is by doing. The numerous Try It Out sections in each chapter first show you how to build something. Then the follow-up How It Works sections explain how everything works. I have also taken this opportunity to further improve the previous edition of this book by addressing feedback from readers and adding additional topics that are important to beginning Android developers.
Although Android programming is a huge topic, my aim for this book is threefold: to get you started with the fundamentals, to help you understand the underlying architecture of the SDK, and to appreciate why things are done in certain ways. It is beyond the scope of any book to cover everything under the sun related to Android programming. However, I am confident that after reading this book (and doing the exercises), you will be well equipped to tackle your next Android programming challenge.
This book is targeted for the beginning Android developer who wants to start developing applications using Google's Android SDK. To truly benefit from this book, you should have some background in programming and at least be familiar with object-oriented programming (OOP) concepts. If you are totally new to Java—the language used for Android development—you might want to take a programming course in Java programming or grab one of many good books on Java programming. In my experience, if you already know C# or VB.NET, learning Java doesn't require too much effort. If you're already comfortable with C# or VB.NET, you should be comfortable just following along with the Try It Outs.
For those totally new to programming, I know the lure of developing mobile apps and making some money is tempting. However, before attempting to try out the examples in this book, I think a better starting point would be to first learn the basics of programming.
This book covers the fundamentals of Android programming using the Android SDK. It is divided into 12 chapters and one appendix.
This book breaks down the task of learning Android programming into several smaller chunks, enabling you to digest each topic before delving into a more advanced one.
If you are a total beginner to Android programming, start with Chapter 1. After you have familiarized yourself with the basics, head to Chapter 2 and get to know the Android Studio IDE. When you are ready, continue with Chapter 3 and gradually move into more advanced topics.
A feature of this book is that all the code samples in each chapter are independent of those discussed in previous chapters. This gives you the flexibility to dive into the topics that interest you and start working on the Try It Out projects.
All the examples in this book run on the Android emulator (which is included as part of the Android SDK and Android Studio). However, to get the most out of this book, it would be useful to have a real Android device (though it's not absolutely necessary).
To help you get the most from the text and keep track of what's happening, a number of conventions are used throughout the book.
As for other conventions in the text:
persistence.properties.We use a monofont type with no highlighting for most code examples.
We use bolding to emphasize code that is of particular importance in the
present context.As you work through the examples in this book, you may choose either to type in all the code manually or to use the source code files that accompany the book. All the source code used in this book is available for download at www.wrox.com. When at the site, simply locate the book's title (use the Search box or one of the title lists) and click the Download Code link on the book's detail page to obtain all the source code for the book.
You'll find the filename of the project you need at the end of the title of the Try it Out features:
We make every effort to ensure that there are no errors in the text or in the code. However, no one is perfect, and mistakes do occur. If you find an error in one of our books, such as a spelling mistake or faulty piece of code, we would be very grateful for your feedback. By sending in errata, you might save another reader hours of frustration and at the same time help us provide even higher-quality information.
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If you don't spot “your” error on the Book Errata page, go to www.wrox.com/contact/techsupport.shtml and complete the form there to send us the error you have found. We'll check the information and, if appropriate, post a message to the book's errata page and fix the problem in subsequent editions of the book.
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