Professional Web 2.0 Programming (Wrox Professional Guides)

552 Pages·2006·8.54 MB·English

by  Eric van der Vlist

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Professional
Web 2.0 Programming
Eric van der Vlist, Alessandro Vernet,
Erik Bruchez, Joe Fawcett, and Danny Ayers
01_087889 ffirs.qxp 10/19/06 3:55 PM Page i
Professional
Web 2.0 Programming
01_087889 ffirs.qxp 10/19/06 3:55 PM Page iii
Professional
Web 2.0 Programming
Eric van der Vlist, Alessandro Vernet,
Erik Bruchez, Joe Fawcett, and Danny Ayers
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Professional Web 2.0 Programming
Published by
Wiley Publishing, Inc.
10475 Crosspoint Boulevard
Indianapolis, IN 46256
www.wiley.com
Copyright © 2007 by Wiley Publishing, Inc., Indianapolis, Indiana
Published simultaneously in Canada
ISBN-13: 978-0-470-08788-6
ISBN-10: 0-470-08788-9
Manufactured in the United States of America
10 9 8 7 6 5 4 3 2 1
1MA/QX/RR/QW/IN
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To my wife Catherine and children Deborah, David, Samuel, and Sarah for
the high tribute they have paid to this book through my lack of availability!
—E. van der V.
Dedicated to my wonderful wife, Yue. You have changed my life for the
best, and I love you more than I can say.
—A.V.
To Carol, for her patience and support during those working evenings and
weekends.
—E.B.
To my wife Gillian and my children, Persephone and Xavier, who make it
all worthwhile.
—J.F.
I dedicate my contribution to this book to our dog Basil, who missed out on
a lot of walks while I worked.
—D.A.
For Virgil Matheson
—M.D.
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About the Authors
Eric van der Vlistis an independent consultant and trainer. His domain of expertise includes Web devel-
opment and XMLtechnologies. He is the creator and main editor of XMLfr.org, the main site dedicated
to XMLtechnologies in French, the author of the O’Reilly books XMLSchemaand RELAX NG, and a
member or the ISO DSDL(http://dsdl.org) working group, which focuses on XMLschema lan-
guages. He is based in Paris and you can reach him by mail ([email protected]) or meet him at one of
the many conferences where he presents his projects.
Alessandro Vernethas been involved with web and XMLtechnologies from day one. Prior to
co-founding Orbeon, he worked at Symantec Corporation as part of the VisualCafe team, working on
the next-generation RAD for web applications. He is the co-author of The Best of Java, received the 1998
Logitech Award for his master’s thesis on Jaskell, and is one of the architects of the open source Orbeon
PresentationServer (OPS) project. His current interests lie in XMLtechnologies and web applications.
He recently implemented an XForms engine using Ajax/JavaScript, co-authored the XMLPipeline
Language specification published by the W3C, and is active in two W3C Working Groups: the XForms
and XMLProcessing Model Working Groups. He holds an MS/CS from the Swiss Institute of
Technology (EPFL) in Lausanne, Switzerland.
Erik Bruchezhas extensive experience in the software industry as a software architect and consultant.
As a former employee of Symantec Corporation, he contributed to the VisualCafe for Java product line.
In 1999, he co-founded Orbeon, Inc. (www.orbeon.com), where he is now an architect of Orbeon
PresentationServer (OPS), an open source web platform for form-based applications that builds on tech-
nologies such as XForms and Ajax. Erik participates in the W3C’s XForms and XMLProcessing Model
working groups. He is the author of articles about web applications and XMLtechnologies and has been
a speaker at conferences such as JavaOne, ObjectWebCon, and XTech. Erik holds an MS/CS degree from
the Swiss Institute of Technology (EPFL) in Lausanne, Switzerland. He spends most of his time between
Switzerland and California and can be reached by email at [email protected].
Joe Fawcettstarted programming in the seventies and briefly worked in IT after leaving full-time educa-
tion. He then pursued a more checkered career before returning to software development in 1994. In
2003 he was awarded the title of Microsoft Most Valuable Professional in XMLfor community contribu-
tions and technical expertise. He currently works in London as senior developer for FTC Kaplan Ltd, a
leading international provider of accountancy and business training.
Danny Ayersis a freelance developer, technical author, and consultant specializing in cutting-edge Web
technologies. His motivation is the belief that with a little encouragement, the Web can be significantly
more useful and interesting than it is now. He’s been a blogger for some five years (http://danny
ayers.com), with a tendency to post material relating to the Semantic Web or cat photos.
Technical Editor Micah Dubinkois an experienced software architect and writer working for the
MobilePlatform group at Yahoo! Inc. He has been programming since the third grade—at the time on a
computer with only 2K of memory. Micah served as an editor and author of the W3C XForms specifica-
tion, publishing a book in print and online, and eventually being awarded the InfoWorld Innovators
2004 award for his effort. Since then, he has contributed to and edited numerous Web 2.0 books and
articles. His blog is at http://dubinko.info/blog/. Micah lives with his wife and two daughters
inSilicon Valley.
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Credits
SeniorAcquisitions Editor Project Coordinators
Jim Minatel Ryan Steffen
Jennifer Theriot
Development Editor
Sara Shlaer Graphics and Production Specialists
Carrie A. Foster
Technical Editor Denny Hager
Micah Dubinko Jennifer Mayberry
Barbara Moore
Production Editor Heather Ryan
Felicia Robinson Alicia B. South
Copy Editor Quality Control Technician
Michael Koch John Greenough
Editorial Manager Proofreading
Mary Beth Wakefield Techbooks
Production Manager Indexing
Tim Tate Infodex Indexing Services, Inc.
Vice President and Executive Group Publisher
Richard Swadley
Vice President and Executive Publisher
Joseph B. Wikert
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Contents
Foreword xvii
Acknowledgments xix
Introduction xxi
Chapter 1: Hello Web 2.0 World 1
Introducing BuzzWatch 1
Charting the Landscape 4
Exploring Behind the Scene 6
Making BuzzWatch a Better Web Citizen 24
Making BuzzWatch More Maintainable 28
Applying the Final Touch 33
Conclusion 35
Chapter 2: Page Presentation 37
Creating Clean and Simple Pages 37
Producing Valid HTML 38
Using Cascading Style Sheets 40
Choosing Appropriate Elements 41
From HTML to XHTML 42
XHTML 1.0 43
XHTML 1.1 43
Why Use XHTML? 44
Differences from HTML 45
The Document Object Model 47
DOM Levels 49
DOM API Overview 49
DOM API Reference 51
Cascading Style Sheets 51
Rounded Corners 52
Tabs 54
Tools 55
The DOM Inspector for Firefox 55
The Web Developer Toolbar for Firefox 57
The Internet Explorer Developer Toolbar 58
DevBoi for Firefox 59
Summary 60
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Contents
Chapter 3: JavaScript and Ajax 61
JavaScript: Understanding Lesser-Known but Crucial Features 61
The undefined Value and Type 62
The === Operator 64
Iterating with for-in 65
Functional Programming 66
Function Arguments 67
JavaScript Optimizations 69
Reducing JavaScript Download Time 69
Keep DOM Updates to a Minimum 70
Ajax 70
It’s All About the User Experience 71
XMLHttpRequest History 71
XMLHttpRequest Example 72
Yahoo! UI Library 75
Google Web Toolkit 78
Handling Memory Leaks 79
Summary 81
Chapter 4: Design Principles 83
Common Design Issues 84
Bookmarks 84
Navigation 88
Minimizing Traffic 89
Support for Down-Level Devices 93
Accessibility Requirements and Guidelines 94
Summary 109
Chapter 5: What’s Next for Web 2.0? 111
XSLT and XPath 111
XSLT Hello World Example 112
More XSLT 114
XSLT Styles 117
More XSLT 119
Using XSLT in a Browser 122
SVG 124
SVG Hello World Example 126
Styling SVG 130
More SVG 132
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