The Busy Coder's Guide to Android Development - CommonsWare

749 Pages·2011·11.21 MB·English

by  Mark L. Murphy

The Busy Coder's Guide to Android
Development
by Mark L. Murphy
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The Busy Coder's Guide to Android Development
by Mark L. Murphy
Copyright © 2008-2011 CommonsWare, LLC. All Rights Reserved.
Printed in the United States of America.
CommonsWare books may be purchased in printed (bulk) or digital form for educational or
business use. For more information, contact [email protected].
Printing History:
Nov 2011:Version 3.7 ISBN: 978-0-9816780-0-9
The CommonsWare name and logo, “Busy Coder's Guide”, and related trade dress are
trademarks of CommonsWare, LLC.
All other trademarks referenced in this book are trademarks of their respective firms.
The publisher and author(s) assume no responsibility for errors or omissions or for damages
resulting from the use of the information contained herein.
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Table of Contents
Welcome to the Warescription!........................................................xxiii
Preface.................................................................................................xxv
Welcome to the Book!..............................................................................xxv
Warescription............................................................................................xxv
Getting Help.............................................................................................xxvi
Book Bug Bounty....................................................................................xxvii
Source Code And Its License................................................................xxviii
Creative Commons and the Four-to-Free (42F) Guarantee...............xxviii
Acknowledgments...................................................................................xxix
The Big Picture.........................................................................................1
What Androids Are Made Of.......................................................................3
Activities.................................................................................................3
Services...................................................................................................4
Content Providers..................................................................................4
Intents.....................................................................................................4
Stuff At Your Disposal..................................................................................5
Storage.....................................................................................................5
Network...................................................................................................5
Multimedia.............................................................................................5
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GPS..........................................................................................................5
Phone Services........................................................................................6
The Big Picture...Of This Book....................................................................6
How To Get Started.................................................................................7
Hardware Requirements..............................................................................7
Java.................................................................................................................8
Install the JDK........................................................................................8
Learn Java...............................................................................................9
Install the Android SDK...............................................................................9
Install the Base Tools............................................................................10
Install the SDKs and Add-Ons.............................................................10
Install the ADT for Eclipse..........................................................................11
Install Apache Ant.......................................................................................13
Set Up the Emulator....................................................................................14
Set Up the Device........................................................................................21
Windows...............................................................................................22
OS X and Linux.....................................................................................23
Your First Android Project....................................................................25
Step #1: Create the New Project.................................................................25
Eclipse...................................................................................................25
Command Line.....................................................................................30
Step #2: Build, Install, and Run the Application in Your Emulator or
Device...........................................................................................................31
Eclipse....................................................................................................31
Command Line.....................................................................................32
Examining Your First Project................................................................37
Project Structure.........................................................................................37
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Root Contents.......................................................................................37
The Sweat Off Your Brow....................................................................38
And Now, The Rest of the Story..........................................................39
What You Get Out Of It......................................................................40
Inside Your Manifest..................................................................................40
In The Beginning, There Was the Root, And It Was Good...............41
An Application For Your Application.................................................42
A Bit About Eclipse................................................................................45
What the ADT Gives You...........................................................................45
Coping with Eclipse....................................................................................46
How to Import a Non-Eclipse Project................................................46
How to Get To DDMS..........................................................................50
How to Create an Emulator.................................................................52
How to Run a Project...........................................................................53
How Not to Run Your Project.............................................................54
Alternative IDEs..........................................................................................55
More on the Tools.......................................................................................55
IDEs...And This Book.................................................................................56
Enhancing Your First Project................................................................57
Supporting Multiple Screens.....................................................................57
Specifying Versions....................................................................................58
Rewriting Your First Project.................................................................63
The Activity.................................................................................................63
Dissecting the Activity...............................................................................64
Building and Running the Activity...........................................................66
About the Remaining Examples................................................................67
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Using XML-Based Layouts....................................................................69
What Is an XML-Based Layout?................................................................69
Why Use XML-Based Layouts?.................................................................70
OK, So What Does It Look Like?...............................................................71
What's With the @ Signs?..........................................................................72
And We Attach These to the Java...How?.................................................72
The Rest of the Story..................................................................................73
Employing Basic Widgets......................................................................77
Assigning Labels.........................................................................................77
Button, Button, Who's Got the Button?...................................................78
Fleeting Images...........................................................................................79
Fields of Green. Or Other Colors...............................................................81
Just Another Box to Check.........................................................................83
Don't Like Checkboxes? How About Toggles?........................................86
Turn the Radio Up......................................................................................87
It's Quite a View.........................................................................................90
Padding.................................................................................................90
Other Useful Properties......................................................................90
Useful Methods.....................................................................................91
Colors.....................................................................................................91
Working with Containers......................................................................93
Thinking Linearly.......................................................................................94
Concepts and Properties.....................................................................94
Example................................................................................................99
The Box Model....................................................................................104
All Things Are Relative.............................................................................106
Concepts and Properties....................................................................106
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Example...............................................................................................109
Overlap..................................................................................................111
Tabula Rasa.................................................................................................113
Concepts and Properties.....................................................................114
Example................................................................................................116
Scrollwork...................................................................................................117
The Input Method Framework.............................................................121
Keyboards, Hard and Soft..........................................................................121
Tailored To Your Needs............................................................................122
Tell Android Where It Can Go.................................................................126
Fitting In....................................................................................................129
Jane, Stop This Crazy Thing!....................................................................130
Using Selection Widgets......................................................................133
Clicks versus Selections.............................................................................133
Adapting to the Circumstances................................................................134
Using ArrayAdapter............................................................................135
Lists of Naughty and Nice.........................................................................136
Selection Modes..................................................................................138
Clicks versus Selections, Revisited....................................................140
Spin Control...............................................................................................141
Grid Your Lions (Or Something Like That...).........................................144
Fields: Now With 35% Less Typing!........................................................148
Galleries, Give Or Take The Art...............................................................152
Getting Fancy With Lists......................................................................155
Getting To First Base.................................................................................155
A Dynamic Presentation...........................................................................158
Inflating Rows Ourselves..........................................................................160
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A Sidebar About Inflation..................................................................160
And Now, Back To Our Story............................................................162
Better. Stronger. Faster.............................................................................163
Using convertView..............................................................................163
Using the Holder Pattern...................................................................165
Interactive Rows........................................................................................167
Still More Widgets and Containers.....................................................175
Pick and Choose........................................................................................175
Time Keeps Flowing Like a River.............................................................180
Seeking Resolution....................................................................................182
Putting It On My Tab................................................................................183
The Pieces............................................................................................184
Wiring It Together..............................................................................185
Adding Them Up................................................................................188
Flipping Them Off.....................................................................................194
Getting In Somebody's Drawer...............................................................200
Other Good Stuff......................................................................................204
Embedding the WebKit Browser........................................................207
A Browser, Writ Small..............................................................................207
Loading It Up.............................................................................................210
Navigating the Waters...............................................................................211
Entertaining the Client.............................................................................212
Settings, Preferences, and Options (Oh, My!)........................................214
Applying Menus....................................................................................217
Flavors of Menu.........................................................................................217
Menus of Options......................................................................................218
Menus in Context.....................................................................................220
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Taking a Peek.............................................................................................221
Yet More Inflation....................................................................................226
Menu XML Structure.........................................................................227
Menu Options and XML....................................................................228
Inflating the Menu.............................................................................229
In the Land of Menus and Honey............................................................231
Showing Pop-Up Messages..................................................................233
Raising Toasts............................................................................................233
Alert! Alert!................................................................................................234
Checking Them Out.................................................................................235
Handling Activity Lifecycle Events.....................................................239
Schroedinger's Activity.............................................................................239
Life, Death, and Your Activity.................................................................240
onCreate() and onDestroy()..............................................................240
onStart(), onRestart(), and onStop().................................................241
onPause() and onResume()...............................................................242
The Grace of State.....................................................................................242
When Activities Die.................................................................................244
Handling Rotation...............................................................................245
A Philosophy of Destruction....................................................................245
It's All The Same, Just Different..............................................................246
Picking and Viewing a Contact.........................................................248
Saving Your State...............................................................................250
Now With More Savings!.........................................................................253
DIY Rotation..............................................................................................255
...But Google Does Not Recommend This........................................259
Forcing the Issue.......................................................................................259
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