iPhone Advanced Projects

384 Pages·2009·5.211 MB·English

by  Joachim Bondo, Dylan Bruzenak, Steve Finkelstein, Owen Goss, Tom Harrington, Peter Honeder, Ray Kiddy, Noel Llopis, Joe Pezzillo, Florian Pflug, Jonathan Saggau, Ben Britten Smith (auth.), Dave Mark (eds.)

iPhone Advanced Projects
■■■
Dave Mark, Series Editor
Joachim Bondo
Ray Kiddy
Dylan Bruzenak
Noel Llopis
Steve Finkelstein
Joe Pezzillo
Owen Goss
Florian Pflug
Tom Harrington
Jonathan Saggau
Peter Honeder
Ben Britten Smith
iPhone Advanced Projects
Copyright © 2009 by Dave Mark, Joachim Bondo, Dylan Bruzenak, Steve Finkelstein, Owen Goss, Tom Harrington,
Peter Honeder, Ray Kiddy, Noel Llopis, Joe Pezzillo, Florian Pflug, Jonathan Saggau, Ben Britten Smith
All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic
or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the
prior written permission of the copyright owner and the publisher.
ISBN-13 (pbk): 978-1-4302-2403-7
ISBN-13 (electronic): 978-1-4302-2404-4
Printed and bound in the United States of America 9 8 7 6 5 4 3 2 1
Trademarked names may appear in this book. Rather than use a trademark symbol with every occurrence of a
trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark owner, with
no intention of infringement of the trademark.
Lead Editor: Clay Andres
Technical Reviewer: Glenn Cole
Developmental Editor: Douglas Pundick
Editorial Board: Clay Andres, Steve Anglin, Mark Beckner, Ewan Buckingham, Tony Campbell, Gary Cornell,
Jonathan Gennick, Michelle Lowman, Matthew Moodie, Jeffrey Pepper, Frank Pohlmann, Ben Renow-
Clarke, Dominic Shakeshaft, Matt Wade, Tom Welsh
Coordinating Editor: Kelly Moritz
Copy Editor: Kim Wimpsett
Compositor: MacPS, LLC
Indexer: Julie Grady
Artist: April Milne
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To my lovely wife, Leonie.
—Ben Britten Smith
To my wife, Malena, who once again gave me the support I hadn’t earned.
—Joachim Bondo
To everyone I know and to everyone I haven’t met yet.
—Dylan Bruzenak
To all of my family and friends for their support and patience with my demanding schedule. To my loving
wife, Michelle, who sustains me and encourages me to take risks. Finally, this one is for my grandmother,
Asya; you will live forever in all our hearts.
—Steve Finkelstein
To the iPhone game developers on Twitter for sharing so much and being such a supportive community.
—Noel Llopis (@snappytouch on Twitter)
I’m so grateful to so many people I can’t possibly hope to name them all individually, so, en masse, let me
thank the blessing that is my family (especially my son), the unstoppable geniuses at Apple, the folks at
Apress who patiently awaited my writing, the incredibly supportive Mac and iPhone indie developer
community, all my clients and customers, my business partners and colleagues, and, of course, the great
ineffable spirit of the universe that makes everything possible.
Thank you!
—Joe Pezzillo
To my family, my friends, the island “La Palma,” and the one who introduced me to it.
—Florian Pflug
To Dr. Michele, who doesn’t let me call her doctor. Thanks for making me
type.
—Jonathan Saggau
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Contents at a Glance
■Contents at a Glance ................................................................................................................................................................ iv
■Contents .................................................................................................................................................................................... v
■Foreword ................................................................................................................................................................................. xi
■About the Technical Reviewer ................................................................................................................................................ xii
■Preface ................................................................................................................................................................................... xiii
Ben Britten Smith ........................................................................................................................................................................ 1
■Everything You Ever Wanted to Know About Particle Systems ................................................................................................ 3
Joachim Bondo .......................................................................................................................................................................... 37
■Chess on the ’Net: Correspondence Gaming with Deep Green ................................................................................................ 39
Tom Harrington .......................................................................................................................................................................... 63
■Audio Streaming: An Exploration into Core Audio .................................................................................................................. 65
Owen Goss ................................................................................................................................................................................. 99
■You Go Squish Now! Debugging on the iPhone ..................................................................................................................... 101
Dylan Bruzenak ........................................................................................................................................................................ 139
■Building Data-Driven Applications with Active Record and SQLite ...................................................................................... 141
Ray Kiddy ................................................................................................................................................................................. 181
■Core Data and Hard-Core Design .......................................................................................................................................... 183
Steve Finkelstein ..................................................................................................................................................................... 209
■Smart In-Application E-mail with Core Data and Three20 ................................................................................................... 211
Florian Pflug and Peter Honeder .............................................................................................................................................. 247
■How iTap Tackles the Challenges of Networking .................................................................................................................. 249
Jonathan Saggau ..................................................................................................................................................................... 277
■Fake It ’Til You Make It: Tips and Tricks for Improving Interface Responsiveness .............................................................. 279
Joe Pezzillo .............................................................................................................................................................................. 311
■Demystifying the Apple Push Notification Service ............................................................................................................... 313
Noel Llopis ............................................................................................................................................................................... 345
■Environment Mapping and Reflections with OpenGL ES ...................................................................................................... 347
■Index ..................................................................................................................................................................................... 365
4iv
Contents
■Contents at a Glance ............................................................................................................... iv(cid:3)
■Contents .................................................................................................................................. v(cid:3)
■Foreword ................................................................................................................................ xi(cid:3)
■About the Technical Reviewer ............................................................................................... xii
■Preface ................................................................................................................................. xiii
Ben Britten Smith ....................................................................................................................... 1(cid:3)
■CHAPTER 1: Everything You Ever Wanted to Know
About Particle Systems .................................................................................................... 3(cid:3)
Adding Life to Your Game with Particles ..................................................................................................................................................5
Basic Particle Systems and You ...............................................................................................................................................................7
Overview of the Sample Code .............................................................................................................................................................8
Basic Game Flow .................................................................................................................................................................................9
The Anatomy of a Particle System ....................................................................................................................................................10
Code! Finally! ....................................................................................................................................................................................12
Slight Tangent About Degenerates ....................................................................................................................................................15
Back to the Code ...............................................................................................................................................................................16
Random Numbers and Initial Conditions ...........................................................................................................................................19
Emitting Particles ..............................................................................................................................................................................20
Tweaking Your Particle System .............................................................................................................................................................21
May the Force Be with Your Particles ...............................................................................................................................................25
Amazing Technicolor Dream Particle .....................................................................................................................................................28
Off on a Tangent: Lerping ..................................................................................................................................................................28
Color-Changing Particles ...................................................................................................................................................................30
Summary ................................................................................................................................................................................................35
v
■ CONTENTS
Joachim Bondo.........................................................................................................................37(cid:3)
■Chapter 2: Chess on the ’Net: Correspondence
Gaming with Deep Green................................................................................................39(cid:3)
Deep Green, an Already Awesome Application......................................................................................................................................40
The Tasks at Hand..................................................................................................................................................................................42
Inviting a Friend to a Game...............................................................................................................................................................43
Accepting the Invitation....................................................................................................................................................................43
Making a Move..................................................................................................................................................................................43
Getting Notified.................................................................................................................................................................................43
The Tools of the Trade............................................................................................................................................................................44
Stop Talking, Start Coding!....................................................................................................................................................................45
Installing the Tools............................................................................................................................................................................45
Coding the Web Service....................................................................................................................................................................47
Accepting the Challenge on the Device.............................................................................................................................................54
Making a Move..................................................................................................................................................................................57
Summary................................................................................................................................................................................................61
Tom Harrington........................................................................................................................63(cid:3)
■Chapter 3: Audio Streaming: An Exploration into Core Audio...............................................65(cid:3)
Hey, I Could Write an App to Play Music................................................................................................................................................66
MPMoviePlayerController: Hey, This Is Easy! Right?..............................................................................................................................66
Finding a Better Approach......................................................................................................................................................................68
The System-Sound Way....................................................................................................................................................................69
AVAudioPlayer: The Not-Available-in-Beta Way................................................................................................................................69
Doing It the Cowboy Way with Core Audio.............................................................................................................................................74
Getting Halfway There: Audio Queue Services..................................................................................................................................74
Getting the Rest of the Way There: Audio File Stream Services........................................................................................................81
Putting It All into an App.........................................................................................................................................................................93
One More Thing.................................................................................................................................................................................93
Launch It!...............................................................................................................................................................................................96
iPhone 3.0 and Further Work.................................................................................................................................................................96
Summary................................................................................................................................................................................................97
Owen Goss................................................................................................................................99(cid:3)
■Chapter 4: You Go Squish Now! Debugging on the iPhone..................................................101(cid:3)
Assumed Knowledge............................................................................................................................................................................102
Objective-C vs. C and C++...................................................................................................................................................................104
While You’re Writing That Code............................................................................................................................................................105
Custom Asserts...............................................................................................................................................................................105
Custom Logging..............................................................................................................................................................................107
Using #define..................................................................................................................................................................................108
Crash!...................................................................................................................................................................................................109
Getting a Crash Log from Your Testers...........................................................................................................................................109
You Have Been Saving Your dSYM Files, Right?.............................................................................................................................110
Symbolicatinga Crash Log..............................................................................................................................................................110
6vi
■ CONTENTS
Using atos.......................................................................................................................................................................................111
Reproducing Rare Crashes...................................................................................................................................................................112
Thread.............................................................................................................................................................................................112
System............................................................................................................................................................................................113
Race Conditions..............................................................................................................................................................................113
The Scientific Method of Debugging....................................................................................................................................................113
Forming a Hypothesis.....................................................................................................................................................................113
Creating a Test for Your Hypothesis................................................................................................................................................114
Proving or Disproving Your Hypothesis...........................................................................................................................................115
Increasing the Probability of the Crash...........................................................................................................................................115
So, You Have a Call Stack....................................................................................................................................................................115
Starting Code...................................................................................................................................................................................115
What Is a Memory Stomp?..............................................................................................................................................................118
Identifying a Mem Stomp................................................................................................................................................................122
Tools to Detect Memory Problems..................................................................................................................................................123
Watching Variables.........................................................................................................................................................................131
Link Map Files.................................................................................................................................................................................135
Summary..............................................................................................................................................................................................137
Dylan Bruzenak......................................................................................................................139(cid:3)
■Chapter 5: Building Data-Driven Applications with
Active Record and SQLite.............................................................................................141(cid:3)
A Short Road Off a High Cliff (How I Got Here)....................................................................................................................................141
Ready! Set! Wait, What? (Why I Decided to Write a To-Do Application)...............................................................................................142
Data-Driven Applications on the iPhone...............................................................................................................................................143
Active Record: A Simple Way of Accessing Data................................................................................................................................144
Writing a Database Wrapper Around the C API: ISDatabase................................................................................................................144
Setting Up the Example Project.......................................................................................................................................................145
Creating and Initializing the Database............................................................................................................................................148
Opening a Database Connection.....................................................................................................................................................149
Making Simple Requests.................................................................................................................................................................152
More Advanced SQL.............................................................................................................................................................................158
Preventing Duplicate Create Statements........................................................................................................................................158
Handling Parameters.......................................................................................................................................................................160
Refactoringand Cleanup.................................................................................................................................................................162
Grouping Statements into Transactions..........................................................................................................................................163
Writing a Simple Active Record Layer: ISModel...................................................................................................................................164
Maintaining the Database Connection............................................................................................................................................165
The Model Object: Grocery Item......................................................................................................................................................165
How Groceries Are Mapped.............................................................................................................................................................166
Saving.............................................................................................................................................................................................168
Updating..........................................................................................................................................................................................170
Deleting...........................................................................................................................................................................................170
Finding Grocery Items.....................................................................................................................................................................171
Putting It All Together......................................................................................................................................................................174
vii
■ CONTENTS
Simple Migration Handling...................................................................................................................................................................176
Alternative Implementations................................................................................................................................................................179
Summary..............................................................................................................................................................................................180
Ray Kiddy...............................................................................................................................181(cid:3)
■Chapter 6: Core Data and Hard-Core Design.......................................................................183(cid:3)
Where Did Core Data Come From?.......................................................................................................................................................184
The Client Is King............................................................................................................................................................................184
A Very First Core Data App...................................................................................................................................................................185
First, Steal Code (Not Music!)..........................................................................................................................................................186
A View to an Object, Any Object......................................................................................................................................................187
Our Very First Crash, or Perhaps Not!.............................................................................................................................................193
CoreData Tutorial for iPhone OS: Managing Model Migrations............................................................................................................194
The Easy Migrations Are Easy.........................................................................................................................................................194
Adding a New Entity........................................................................................................................................................................197
Using Key-Value Coding to Create a Reusable Object..........................................................................................................................199
Remote Databases: It’s All Net!............................................................................................................................................................203
Summary..............................................................................................................................................................................................206
Steve Finkelstein....................................................................................................................209(cid:3)
■Chapter 7: mart In-Application E-mail with
Core Data and Three20.................................................................................................211(cid:3)
Planning a Simple Offline SMTP Client.................................................................................................................................................212
Creating the User Interface..................................................................................................................................................................213
Diving into Xcode............................................................................................................................................................................213
Setting Up Instance Variables in OfflineMailerAppDelegate.h.........................................................................................................215
Initializing the UIApplication Delegate.............................................................................................................................................217
Working with Core Data.......................................................................................................................................................................218
Understanding the Core Data Stack................................................................................................................................................221
Adding Three20...............................................................................................................................................................................221
Journeying Through the User Interface................................................................................................................................................224
Managing Top-Level Data with DataManager......................................................................................................................................226
Diving into Three20 and TTMessageController....................................................................................................................................228
Composing and Sending Messages.....................................................................................................................................................230
Creating the Core Data Model..............................................................................................................................................................235
Hacking SKPSMTPMessage to Support Threaded Message Sending..................................................................................................239
Setting Up the NSRunLoop on SKPSMTPMessage...............................................................................................................................239
Switching the Bits Back to Online Mode..............................................................................................................................................241
Summary..............................................................................................................................................................................................244
Florian Pflug and Peter Honeder............................................................................................247(cid:3)
■Chapter 8: How iTap Tackles the Challenges of Networking...............................................249(cid:3)
Meet iTap and iTap Receiver................................................................................................................................................................250
iTap.................................................................................................................................................................................................251
iTap Receiver...................................................................................................................................................................................251
How the Idea for iTap Emerged and Evolved.......................................................................................................................................252
8viii
■ CONTENTS
The Main Challenges............................................................................................................................................................................252
No Physical Buttons on the iPhone.................................................................................................................................................252
Third-Party Applications Cannot Use USB or Bluetooth..................................................................................................................253
Supporting Both Mac and PC..........................................................................................................................................................254
User-Friendliness Demands Autodiscovery of Computers and Devices..........................................................................................255
WiFi Networking on the iPhone from a Programmer’s Perspective.....................................................................................................255
About the Sample Code...................................................................................................................................................................256
Introducing Sockets........................................................................................................................................................................257
Creating a Socket............................................................................................................................................................................258
Using CFSocket to React to Networking Events..............................................................................................................................262
Querying the Network Configuration...............................................................................................................................................264
Contacting All Devices on the Network...........................................................................................................................................267
Detecting WiFi Availability...............................................................................................................................................................268
Playing by the Power Management Rules.......................................................................................................................................269
The Networking Subsystem of iTap.....................................................................................................................................................271
To use Bonjour or Not to Use Bonjour.............................................................................................................................................271
Using Notifications to Communicate Between Components...........................................................................................................272
Our Custom Autodiscovery Solution................................................................................................................................................273
Summary..............................................................................................................................................................................................275
Jonathan Saggau....................................................................................................................277(cid:3)
■Chapter 9: Fake It ’Til You Make It: Tips and Tricks for
Improving Interface Responsiveness...........................................................................279(cid:3)
Plotting of Historical Stock Prices with AAPLot....................................................................................................................................280
Storing Data Between Runs............................................................................................................................................................283
Using Plists to Persist Data.............................................................................................................................................................284
Saving Data to the iPhone Application Sandbox.............................................................................................................................285
Shipping AAPLot with Placeholder Data...............................................................................................................................................286
Extending the App for Multiple Stock Graphs: StockPlot.....................................................................................................................288
Concurrency.........................................................................................................................................................................................292
NSOperation, NSOperationQueue, and Blocks................................................................................................................................293
Installing the Plausible Blocks Compiler and Adding It to the Project.............................................................................................294
Using Blocks, NSOperation, and NSOperationQueue in StockPlot..................................................................................................295
Displaying Large Amounts of Data Efficiently......................................................................................................................................298
Zooming a UIScrollView.......................................................................................................................................................................300
UIScrollView Zooming Under the Covers.........................................................................................................................................300
Resetting Resolution in a UIScrollView after a Zoom Operation......................................................................................................301
Drawing into an Off-Screen Context....................................................................................................................................................304
Observations, Tips, and Tricks.............................................................................................................................................................309
Summary..............................................................................................................................................................................................310
Joe Pezzillo............................................................................................................................311(cid:3)
■Chapter 10: Demystifying the Apple Push Notification Service...........................................313(cid:3)
What Is the Apple Push Notification Service?......................................................................................................................................314
What You’ll Need..................................................................................................................................................................................314
ix
■ CONTENTS
Step 1: Create the Client......................................................................................................................................................................314
The Application Delegate................................................................................................................................................................315
Handling Incoming Notifications.....................................................................................................................................................317
Sounds............................................................................................................................................................................................318
Build and Go! Er, Not So Fast..........................................................................................................................................................318
Step 2: Create the Certificate...............................................................................................................................................................319
A Walk-Through of the Program Portal Process..............................................................................................................................319
Back to the Portal............................................................................................................................................................................328
Add the Mobile Provisioning File for Code Signing.........................................................................................................................329
Step 3: Set Up the Server.....................................................................................................................................................................331
A Walk-Through of What This Script Does......................................................................................................................................333
Download Server File......................................................................................................................................................................334
The Home Stretch................................................................................................................................................................................336
Wiring Up the Client........................................................................................................................................................................336
Additional Considerations/Advanced Topics........................................................................................................................................341
Feedback Server.............................................................................................................................................................................341
SSL Server Connections..................................................................................................................................................................342
Moving from Development Sandbox to Production.........................................................................................................................342
Development vs. Ad Hoc.................................................................................................................................................................343
Mobile Provisioning Files................................................................................................................................................................343
Debugging.......................................................................................................................................................................................343
User Experience..............................................................................................................................................................................343
Open Source Code...........................................................................................................................................................................344
Hosted Solutions.............................................................................................................................................................................344
Summary..............................................................................................................................................................................................344
Noel Llopis..............................................................................................................................345(cid:3)
■Chapter 11: Environment Mapping and Reflections
with OpenGL ES............................................................................................................347(cid:3)
The Beginnings.....................................................................................................................................................................................347
First Steps: OpenGL Lighting................................................................................................................................................................349
Turning to Environment Mapping.........................................................................................................................................................352
Spherical Environment Mapping Implementation................................................................................................................................353
Combining Environment Mapping and Diffuse Textures......................................................................................................................356
Per-Pixel Reflections.......................................................................................................................................................................359
iPhone 3GS......................................................................................................................................................................................362
Summary..............................................................................................................................................................................................363
Index.......................................................................................................................................365
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