Hello, Android: Introducing Google's Mobile Development Platform (Pragmatic Programmers)

251 Pages·2009·2.34 MB·English

by  Ed Burnette

What readers are saying about Hello, Android
This is a most excellent book: very well written, easy to read, and fun.
In addition, any of Android’s quirks are explained along with just the
right amount of detail to ensure quality programming principles are
followed.
Anthony Stevens
Founder and CTO, PocketJourney and Top 20 Winner of
Google Android Competition
Ed Burnette covers an impressive amount of ground in a nicely com-
pact book while retaining the popular Pragmatic style. For the mate-
rial on 2D and 3D graphics alone, this is worthy of a spot in any
Android developer’s library.
Mark Murphy
Founder, CommonsWare
I remember when I first started to work with Android; it was like a
huge maze. With this book, the introduction would have been much
less painful. I am convinced that by reading this book new Android
programmers will have an easier start.
Gabor Paller
Senior Software Architect, OnRelay, Ltd.
Hello, Android
Introducing Google’s
Mobile Development Platform, 2nd Edition
Ed Burnette
The Pragmatic Bookshelf
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Allrightsreserved.
Nopartofthispublicationmaybereproduced,storedinaretrievalsystem,ortransmit-
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PrintedintheUnitedStatesofAmerica.
ISBN-10:1-934356-49-2
ISBN-13:978-1-934356-49-4
Printedonacid-freepaper.
P1.0printing,October2009
Version:2009-10-6
Contents
Acknowledgments 9
Preface 10
What Makes Android Special? . . . . . . . . . . . . . . . . . . 10
Who Should Read This Book? . . . . . . . . . . . . . . . . . . . 11
What’s in This Book? . . . . . . . . . . . . . . . . . . . . . . . . 12
What’s New for Cupcake? . . . . . . . . . . . . . . . . . . . . . 12
What’s New for Donut? . . . . . . . . . . . . . . . . . . . . . . . 13
Online Resources . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Fast-Forward >> . . . . . . . . . . . . . . . . . . . . . . . . . . 14
I Introducing Android 15
1 Quick Start 16
1.1 Installing the Tools . . . . . . . . . . . . . . . . . . . . . 16
1.2 Creating Your First Program . . . . . . . . . . . . . . . . 20
1.3 Running on the Emulator . . . . . . . . . . . . . . . . . 20
1.4 Running on a Real Phone . . . . . . . . . . . . . . . . . 23
1.5 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 24
2 Key Concepts 27
2.1 The Big Picture . . . . . . . . . . . . . . . . . . . . . . . 27
2.2 It’s Alive! . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
2.3 Building Blocks . . . . . . . . . . . . . . . . . . . . . . . 36
2.4 Using Resources . . . . . . . . . . . . . . . . . . . . . . 37
2.5 Safe and Secure . . . . . . . . . . . . . . . . . . . . . . . 38
2.6 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 39
CONTENTS 6
II Android Basics 40
3 Designing the User Interface 41
3.1 Introducing the Sudoku Example. . . . . . . . . . . . . 41
3.2 Designing by Declaration . . . . . . . . . . . . . . . . . 42
3.3 Creating the Opening Screen . . . . . . . . . . . . . . . 43
3.4 Using AlternateResources . . . . . . . . . . . . . . . . . 51
3.5 Implementing an About Box . . . . . . . . . . . . . . . . 54
3.6 Applying a Theme . . . . . . . . . . . . . . . . . . . . . . 59
3.7 Adding a Menu . . . . . . . . . . . . . . . . . . . . . . . 60
3.8 Adding Settings . . . . . . . . . . . . . . . . . . . . . . . 63
3.9 Startinga New Game . . . . . . . . . . . . . . . . . . . . 65
3.10 Debugging with Log Messages . . . . . . . . . . . . . . . 67
3.11 Debugging with the Debugger . . . . . . . . . . . . . . . 68
3.12 Exiting the Game . . . . . . . . . . . . . . . . . . . . . . 68
3.13 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 69
4 Exploring 2D Graphics 70
4.1 Learning the Basics . . . . . . . . . . . . . . . . . . . . . 70
4.2 Adding Graphics to Sudoku . . . . . . . . . . . . . . . . 75
4.3 Handling Input . . . . . . . . . . . . . . . . . . . . . . . 84
4.4 The Rest of the Story . . . . . . . . . . . . . . . . . . . . 90
4.5 Making More Improvements . . . . . . . . . . . . . . . . 99
4.6 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 100
5 Multimedia 101
5.1 Playing Audio . . . . . . . . . . . . . . . . . . . . . . . . 101
5.2 Playing Video . . . . . . . . . . . . . . . . . . . . . . . . 107
5.3 Adding Sounds to Sudoku . . . . . . . . . . . . . . . . . 112
5.4 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 115
6 Storing Local Data 116
6.1 Adding Options to Sudoku . . . . . . . . . . . . . . . . . 116
6.2 Continuing an Old Game . . . . . . . . . . . . . . . . . 118
6.3 Remembering the Current Position . . . . . . . . . . . . 120
6.4 Accessing the Internal File System . . . . . . . . . . . . 122
6.5 Accessing SD Cards . . . . . . . . . . . . . . . . . . . . 123
6.6 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 124
CONTENTS 7
III Beyond the Basics 125
7 The Connected World 126
7.1 Browsing by Intent . . . . . . . . . . . . . . . . . . . . . 127
7.2 Web with a View . . . . . . . . . . . . . . . . . . . . . . . 131
7.3 From JavaScript to Java and Back . . . . . . . . . . . . 136
7.4 Using Web Services . . . . . . . . . . . . . . . . . . . . . 143
7.5 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 154
8 Locating and Sensing 155
8.1 Location, Location, Location . . . . . . . . . . . . . . . . 155
8.2 Set Sensors to Maximum . . . . . . . . . . . . . . . . . 161
8.3 Bird’s-Eye View . . . . . . . . . . . . . . . . . . . . . . . 164
8.4 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 170
9 Putting SQL to Work 171
9.1 Introducing SQLite . . . . . . . . . . . . . . . . . . . . . 171
9.2 SQL 101 . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
9.3 Hello, Database . . . . . . . . . . . . . . . . . . . . . . . 174
9.4 Data Binding. . . . . . . . . . . . . . . . . . . . . . . . . 182
9.5 Using a ContentProvider . . . . . . . . . . . . . . . . . . 185
9.6 Implementing a ContentProvider . . . . . . . . . . . . . 188
9.7 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 189
10 3D Graphics in OpenGL 191
10.1 Understanding 3D Graphics . . . . . . . . . . . . . . . . 191
10.2 Introducing OpenGL . . . . . . . . . . . . . . . . . . . . 192
10.3 Building an OpenGL Program . . . . . . . . . . . . . . . 193
10.4 Rendering the Scene . . . . . . . . . . . . . . . . . . . . 195
10.5 Building a Model . . . . . . . . . . . . . . . . . . . . . . 199
10.6 Lights, Camera, ... . . . . . . . . . . . . . . . . . . . . . 202
10.7 Action! . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
10.8 Applying Texture . . . . . . . . . . . . . . . . . . . . . . 205
10.9 Peekaboo . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
10.10 Measuring Smoothness . . . . . . . . . . . . . . . . . . 210
10.11 Fast-Forward >>. . . . . . . . . . . . . . . . . . . . . . . 211
CONTENTS 8
IV Appendixes 212
A Java vs. the Android Language and APIs 213
A.1 Language Subset . . . . . . . . . . . . . . . . . . . . . . 213
A.2 Standard Library Subset . . . . . . . . . . . . . . . . . . 215
A.3 Third-Party Libraries . . . . . . . . . . . . . . . . . . . . 216
B Hello, Widget 217
B.1 Creating Your First Widget . . . . . . . . . . . . . . . . . 217
B.2 Calling All Widgets! . . . . . . . . . . . . . . . . . . . . . 219
B.3 Stretchto Fit. . . . . . . . . . . . . . . . . . . . . . . . . 220
B.4 The Rest of the Story . . . . . . . . . . . . . . . . . . . . 221
B.5 Running the Widget. . . . . . . . . . . . . . . . . . . . . 222
B.6 Keeping Up to Date . . . . . . . . . . . . . . . . . . . . . 224
B.7 Go Wild . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
C Publishing to the Android Market 227
C.1 Preparing . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
C.2 Signing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
C.3 Publishing . . . . . . . . . . . . . . . . . . . . . . . . . . 231
C.4 Updating . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
C.5 Closing thoughts . . . . . . . . . . . . . . . . . . . . . . 233
D Bibliography 235
Index 236
Acknowledgments
I’d like to thankthe many people who made this book possible, includ-
ing my reviewers Anthony Stevens, Gabor Paller, Fred Burke, Dianne
Hackborn, and Laurent Pontier for their attention to detail; Al Sutton
for creating an early Donut SDK for developers; my editor Susannah
Pfalzer for her great suggestions and good cheer in the face of impossi-
ble deadlines; and especially my family for their patience in putting up
with all the long hours.
CONTENTS 8
IV Appendixes 212
A Java vs. the Android Language and APIs 213
A.1 Language Subset . . . . . . . . . . . . . . . . . . . . . . 213
A.2 Standard Library Subset . . . . . . . . . . . . . . . . . . 215
A.3 Third-Party Libraries . . . . . . . . . . . . . . . . . . . . 216
B Hello, Widget 217
B.1 Creating Your First Widget . . . . . . . . . . . . . . . . . 217
B.2 Calling All Widgets! . . . . . . . . . . . . . . . . . . . . . 219
B.3 Stretchto Fit. . . . . . . . . . . . . . . . . . . . . . . . . 220
B.4 The Rest of the Story . . . . . . . . . . . . . . . . . . . . 221
B.5 Running the Widget. . . . . . . . . . . . . . . . . . . . . 222
B.6 Keeping Up to Date . . . . . . . . . . . . . . . . . . . . . 224
B.7 Go Wild . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
C Publishing to the Android Market 227
C.1 Preparing . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
C.2 Signing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
C.3 Publishing . . . . . . . . . . . . . . . . . . . . . . . . . . 231
C.4 Updating . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
C.5 Closing thoughts . . . . . . . . . . . . . . . . . . . . . . 233
D Bibliography 235
Index 236