Android NDK Beginner's Guide

436 Pages·2012·5.63 MB·English

Android NDK
Beginner's Guide
Discover the native side of Android and inject the power
of C/C++ in your applications

Sylvain Ratabouil
BIRMINGHAM - MUMBAI
Android NDK
Beginner's Guide
Copyright © 2012 Packt Publishing
All rights reserved. No part of this book may be reproduced, stored in a retrieval system,
or transmitted in any form or by any means, without the prior written permission of the
publisher, except in the case of brief quotations embedded in critical articles or reviews.
Every effort has been made in the preparation of this book to ensure the accuracy of the
information presented. However, the information contained in this book is sold without
warranty, either express or implied. Neither the author nor Packt Publishing, and its dealers
and distributors will be held liable for any damages caused or alleged to be caused directly
or indirectly by this book.
Packt Publishing has endeavored to provide trademark information about all of the companies
and products mentioned in this book by the appropriate use of capitals. However, Packt
Publishing cannot guarantee the accuracy of this information.
First published: January 2012
Production Reference: 1200112
Published by Packt Publishing Ltd.
Livery Place
35 Livery Street
Birmingham B3 2PB, UK.
ISBN 978-1-84969-152-9
www.packtpub.com
Cover Image by Marcus Grandon ([email protected])
Credits
Author Project Coordinator
Sylvain Ratabouil Jovita Pinto
Reviewers Proofreader
Marko Gargenta Lynda Sliwoski
Dr. Frank Grützmacher
Indexer
Robert Mitchell
Hemangini Bari
Acquisition Editor
Graphics
Sarah Cullington
Valentina D'silva
Lead Technical Editor
Production Coordinators
Dayan Hyames
Prachali Bhiwandkar
Technical Editor Melwyn D'sa
Pramila Balan Nilesh Mohite
Copy Editor Cover Work
Laxmi Subramanian Alwin Roy
About the Author
Sylvain Ratabouil is a confirmed IT consultant with experience in C++ and Java
technologies. He worked for the space industry and got involved in aeronautic projects at
Valtech Technologies where he now takes part in the Digital Revolution.
Sylvain earned the master's degree in IT from Paul Sabatier University in Toulouse and did
M.Sc. in Computer Science from Liverpool University.
As a technology lover, he is passionate about mobile technologies and cannot live or sleep
without his Android smartphone.
I would like to thank Steven Wilding for offering me to write this book;
Sneha Harkut and Jovita Pinto for awaiting me with so much patience;
Reshma Sundaresan, and Dayan Hyames for putting this book on the
right track; Sarah Cullington for helping me finalizing this book;
Dr. Frank Grützmacher, Marko Gargenta, and Robert Mitchell for
all their helpful comments.
About the Reviewers
Dr. Frank Grützmacher has worked for several major German firms in the area of large
distributed systems. He was an early user of different Corba implementations in the past.
He got his Ph.D. in the field of electrical engineering, but with the focus on distributed
heterogeneous systems. In 2010, he was involved in a project, which changed parts of the
Android platform for a manufacturer. From there, he got his knowledge about the android
NDK and native processes on this platform.
He has already worked as a reviewer for another Android 3.0 book.
Robert Mitchell is an MIT graduate with over 40 years experience in Information
Technology and is semiretired. He has developed software for all the big iron companies:
IBM, Amdahl, Fujitsu, National Semiconductor, and Storage Technology. Software companies
include Veritas and Symantec. Recent languages that he knows are Ruby and Java, with a
long background in C++.
www.PacktPub.com
Support files, eBooks, discount offers and more
You might want to visit www.PacktPub.com for support files and downloads related to
your book.
Did you know that Packt offers eBook versions of every book published, with PDF and ePub
files available? You can upgrade to the eBook version at www.PacktPub.com and as a print
book customer, you are entitled to a discount on the eBook copy. Get in touch with us at
[email protected] for more details.
At www.PacktPub.com, you can also read a collection of free technical articles, sign up for
a range of free newsletters and receive exclusive discounts and offers on Packt books and
eBooks.
http://PacktLib.PacktPub.com
Do you need instant solutions to your IT questions? PacktLib is Packt's online digital book
library. Here, you can access, read and search across Packt's entire library of books.
Why Subscribe?
‹ Fully searchable across every book published by Packt
‹ Copy and paste, print and bookmark content
‹ On demand and accessible via web browser
Free Access for Packt account holders
If you have an account with Packt at www.PacktPub.com, you can use this to access
PacktLib today and view nine entirely free books. Simply use your login credentials for
immediate access.
Table of Contents
Preface 1
Chapter 1: Setting Up your Environment 7
Getting started with Android development 7
Setting up Windows 8
Time for action – preparing Windows for Android development 8
Installing Android development kits on Windows 12
Time for action – installing Android SDK and NDK on Windows 13
Setting up Mac OS X 18
Time for action – preparing Mac OS X for Android development 18
Installing Android development kits on Mac OS X 20
Time for action – installing Android SDK and NDK on Mac OS X 20
Setting up Linux 22
Time for action – preparing Ubuntu Linux for Android development 22
Installing Android development kits on Linux 27
Time for action – installing Android SDK and NDK on Ubuntu 27
Setting up the Eclipse development environment 29
Time for action – installing Eclipse 29
Emulating Android 33
Time for action – creating an Android virtual device 33
Developing with an Android device on Windows and Mac OS X 37
Time for action – setting up your Android device on Windows and Mac OS X 37
Developing with an Android device on Linux 39
Time for action – setting up your Android device on Ubuntu 39
Troubleshooting a development device 42
Summary 43
Chapter 2: Creating, Compiling, and Deploying Native Projects 45
Compiling and deploying NDK sample applications 46
Time for action – compiling and deploying the hellojni sample 46
Table of Contents
Exploring Android SDK tools 51
Android debug bridge 51
Project configuration tool 54
Creating your first Android project using eclipse 56
Time for action – initiating a Java project 56
Introducing Dalvik 59
Interfacing Java with C/C++ 60
Time for action – calling C code from Java 60
More on Makefiles 65
Compiling native code from Eclipse 67
Time for action – creating a hybrid Java/C/C++ project 67
Summary 72
Chapter 3: Interfacing Java and C/C++ with JNI 73
Working with Java primitives 74
Time for action – building a native key/value store 75
Referencing Java objects from native code 85
Time for action – saving a reference to an object in the Store 85
Local and global JNI references 90
Throwing exceptions from native code 91
Time for action – raising exceptions from the Store 92
JNI in C++ 96
Handling Java arrays 96
Time for action – saving a reference to an object in the Store 97
Checking JNI exceptions 106
Summary 107
Chapter 4: Calling Java Back from Native Code 109
Synchronizing Java and native threads 110
Time for action – running a background thread 111
Attaching and detaching threads 120
More on Java and native code lifecycles 121
Calling Java back from native code 122
Time for action – invoking Java code from a native thread 122
More on callbacks 133
JNI method definitions 134
Processing bitmaps natively 135
Time for action – decoding camera feed from native code 136
Summary 146
Chapter 5: Writing a Fully-native Application 147
Creating a native activity 148
Time for action – creating a basic native activity 148
[ ii ]
Table of Contents
Handling activity events 155
Time for action – handling activity events 155
More on Native App Glue 166
UI thread 167
Native thread 168
Android_app structure 170
Accessing window and time natively 171
Time for action – displaying raw graphics and implementing a timer 172
More on time primitives 181
Summary 181
Chapter 6: Rendering Graphics with OpenGL ES 183
Initializing OpenGL ES 184
Time for action – initializing OpenGL ES 184
Reading PNG textures with the asset manager 193
Time for action – loading a texture in OpenGL ES 194
Drawing a sprite 208
Time for action – drawing a Ship sprite 209
Rendering a tile map with vertex buffer objects 220
Time for action – drawing a tile-based background 221
Summary 238
Chapter 7: Playing Sound with OpenSL ES 239
Initializing OpenSL ES 241
Time for action – creating OpenSL ES engine and output 241
More on OpenSL ES philosophy 248
Playing music files 249
Time for action – playing background music 249
Playing sounds 256
Time for action – creating and playing a sound buffer queue 257
Event callback 266
Recording sounds 268
Summary 272
Chapter 8: Handling Input Devices and Sensors 273
Interacting with Android 274
Time for action – handling touch events 276
Detecting keyboard, D-Pad, and Trackball events 288
Time for action – handling keyboard, D-Pad, and trackball, natively 289
Probing device sensors 298
Time for action – turning your device into a joypad 300
Summary 313
[ iii ]