Android in Practice

647 Pages·2011·13.1 MB·English

by  Charlie Collins

Charlie Collins
Michael Galpin
Matthias Käppler
P
IN RACTICE
Includes 91 Techniques
M A N N I N G
Android in Practice

Android in Practice
CHARLIE COLLINS
MICHAEL D. GALPIN
MATTHIAS KÄPPLER
MANNING
SHELTER ISLAND
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ISBN 9781935182924
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1 2 3 4 5 6 7 8 9 10 – MAL – 16 15 14 13 12 11
brief contents
P 1 B ......................................1
ART ACKGROUND AND FUNDAMENTALS
1 ■ Introducing Android 3
2 ■ Android application fundamentals 40
3 ■ Managing lifecycle and state 73
P 2 R ......................................................99
ART EAL WORLD RECIPES
4 ■ Getting the pixels perfect 101
5 ■ Managing background tasks with Services 155
6 ■ Threads and concurrency 189
7 ■ Storing data locally 224
8 ■ Sharing data between apps 266
9 ■ HTTP networking and web services 295
10 ■ Location is everything 334
11 ■ Appeal to the senses using multimedia 363
12 ■ 2D and 3D drawing 402
P 3 B ...................................441
ART EYOND STANDARD DEVELOPMENT
13 ■ Testing and instrumentation 443
14 ■ Build management 489
15 ■ Developing for Android tablets 540
v

contents
preface xiii
acknowledgments xv
about this book xviii
about the cover illustration xxii
P 1 B ............................1
ART ACKGROUND AND FUNDAMENTALS
1 Introducing Android 3
1.1 Android in a nutshell 5
1.2 Hello Android! 9
1.3 Java, but not Java Java 19
1.4 Linux, but not Linux Linux 24
1.5 More capabilities with native libraries 29
1.6 Tools of the trade 32
1.7 Summary 38
2 Android application fundamentals 40
2.1 The DealDroid application 41
2.2 Core building blocks 43
vii
viii CONTENTS
2.3 Application manifest 44
2.4 Resources 46
2.5 Layout, views, and widgets 49
2.6 Activities 51
2.7 Adapters 59
2.8 Intents and IntentFilters 63
2.9 The Application object 69
2.10 Summary 71
3 Managing lifecycle and state 73
3.1 Defining an Android application 74
3.2 Knowing the Activity lifecycle 79
3.3 Controlling Activity instance state 90
3.4 Getting things done within a task 95
3.5 Summary 97
P 2 R ............................................99
ART EAL WORLD RECIPES
4 Getting the pixels perfect 101
4.1 The MyMovies application 102
4.2 View hierarchies and rendering 103
4.3 Arranging views in layouts 106
TECHNIQUE 1 The merge and include directives 114
4.4 Expanding on ListView and Adapter 117
TECHNIQUE 2 Managing a stateful list 118
TECHNIQUE 3 Header and footer views 122
4.5 Applying themes and styles 125
TECHNIQUE 4 Applying and writing styles 125
TECHNIQUE 5 Applying and writing themes 127
TECHNIQUE 6 Styling ListView backgrounds 129
4.6 Working with drawables 133
TECHNIQUE 7 Working with shape drawables 134
TECHNIQUE 8 Working with selector drawables 138
TECHNIQUE 9 Scaling views with nine-patch drawables 141
4.7 Creating portable user interfaces 144
TECHNIQUE 10 Automatically scaling to different screens 144
CONTENTS ix
TECHNIQUE 11 Loading configuration dependent resources 149
TECHNIQUE 12 Programming pixel-independently 152
4.8 Summary 154
5 Managing background tasks with Services 155
5.1 It’s all about the multitasking 156
5.2 Why services and how to use them 157
TECHNIQUE 13 Creating a Service 158
TECHNIQUE 14 Starting a Service automatically 161
TECHNIQUE 15 Communicating with a Service 163
TECHNIQUE 16 Using a Service for caching data 169
TECHNIQUE 17 Creating notifications 171
5.3 Scheduling and Services 176
TECHNIQUE 18 Using the AlarmManager 177
TECHNIQUE 19 Keeping Services awake 180
TECHNIQUE 20 Using Cloud to Device Messaging 183
5.4 Summary 187
6 Threads and concurrency 189
6.1 Concurrency in Android 190
TECHNIQUE 21 Basic threading 191
TECHNIQUE 22 Communicating change between threads 195
TECHNIQUE 23 Managing threads in thread pools 200
6.2 Working with AsyncTask 205
TECHNIQUE 24 Implementing jobs with AsyncTask 206
TECHNIQUE 25 Preparing for configuration changes 210
6.3 Miscellaneous techniques 216
TECHNIQUE 26 Displaying splash screens with timers 216
TECHNIQUE 27 Implementing custom message loops 219
6.4 Summary 223
7 Storing data locally 224
7.1 Reading and writing files 225
TECHNIQUE 28 Using internal storage 226
TECHNIQUE 29 Using external storage 230
TECHNIQUE 30 Using cache directories 235
TECHNIQUE 31 Making sure files are saved with sync 236
7.2 Maintaining preferences 237
TECHNIQUE 32 Reading and writing preference data 237
TECHNIQUE 33 Using a PreferenceActivity 238