advanced Flex Application Development Building Rich Media X phần 1 docx

The authors, leading Flash platform developers at Almer/Blank, working with Adobe User Group communities, are the creators of the Rich Media Exchange RMX, a social media network for Ad

this print for reference only—size & color not accurate spine = 0.9682" 512 page count

goes far further The authors, leading Flash platform developers at Almer/Blank,

working with Adobe User Group communities, are the creators of the Rich Media

Exchange (RMX), a social media network for Adobe developers In covering just

how the RMX was built, this book contains all the knowledge you need to build

similar large-scale Rich Internet Applications with Adobe Flex.

From the inception of the idea through to deployment, the authors show the

techniques needed to plan and build advanced applications You’ll learn how to

use forms, styles, validators, video, sound analysis, and framework caching, ensuring

you make the most of the new features introduced in Flex 3.

Powerful applications require solid back ends This book shows how to hook up

a Flex application to PHP back-end systems such as Drupal and OpenAds You’ll

learn how various parts of the RMX were built, including the blogs, event calendar,

jobs board, and advertising system—elements that come together to really showcase

the power of Flex.

The RMX is built by Adobe Developers for Adobe Developers—a rewarding

community relationship that guarantees results The same spirit is carried into this

book, with the authors wanting and helping to take you to the next level of Flash

Platform application development.

Blank Otuome Gonzalez Charlton

OMAR GONzALEz, AND CHRIs CHARLTON Foreword by James Talbot,

Principal Instructor, Adobe systems IncorporatedAdvancED

Flex Application Development

Building Rich Media X

Use the latest Flex 3 enhancements including runtime shared libraries and framework caching

see how to integrate your dynamic Flex interfaces with back-end systems like PHP, Drupal, and

OpenAds so you can build large-scale applications from end to end

Make your Flex applications recognizable to search engines with sEO optimization techniques for higher rankings and results placement

US $54.99 Mac/PC compatible www.friendsofed.com

In this book you’ll learn how to

Effectively plan, wireframe, specify, develop, and release large-scale Flex

applications, and discover what other development tools you’ll want to start

using immediately

Make your Flex applications look less like Flex with advanced styling

and skinning techniques

Harness advanced Flex form features, including coding validators and building

your custom form components

Implement a robust advertising system for a Flex application using OpenAds

Build powerful, custom multimedia players in Flex, including video players with

the native VideoDisplay class and from scratch, and music players with advanced

AdvancED Flex Application

Development

Building Rich Media X

R Blank Hasan Otuome Omar Gonzalez Chris Charlton

Kinetic Publishing Services, LLC

Cover Image Designer

AdvancED Flex Application Development:

Building Rich Media X

Copyright © 2008 by R Blank, Hasan Otuome, Omar Gonzalez, and Chris Charlton 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): 978-1-59059-896-2 ISBN-10 (pbk): 1-59059-896-2 ISBN-13 (electronic): 978-1-4302-0441-1 ISBN-10 (electronic): 1-4302-0441-9 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.

Distributed to the book trade worldwide by Springer-Verlag New York, Inc., 233 Spring Street, 6th Floor, New York, NY 10013 Phone 1-800-SPRINGER, fax 201-348-4505, e-mail orders-ny@springer-sbm.com, or visit www.springeronline.com For information on translations, please contact Apress directly at 2855 Telegraph Avenue, Suite 600, Berkeley, CA 94705

Phone 510-549-5930, fax 510-549-5939, e-mail info@apress.com, or visit www.apress.com.

The information in this book is distributed on an “as is” basis, without warranty Although every precaution has been taken in the preparation of this work, neither the author(s) nor Apress shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in this work The source code for this book is freely available to readers at www.friendsofed.com in the Downloads section.

Credits

To my parents, Marion and Martin, and my brother, Jonathan, for all they have given me in life, especially the ability to communicate my thoughts fluently, the confidence to do so abundantly, and the drive to keep doing it To my amazing team at Almer/Blank who make it possible for me to do everything I do, through their outstanding skills, vision, imagination, drive, and dedication To Stephanie, who for years told me that I would write a book, whether I wanted to or not And, of course, to Puck and Pippin, who never once complained

when I stayed up writing till 4 a.m., even if that meant I forgot to feed them.

here if it weren’t for everything you’ve taught me—thank you.

Quisiera dedicar este libro a mis padres, Juan y Maria Reyna Gonzalez No hay palabras para expresar el amor y agradecimiento por todo lo que han hecho por mi No estaria aqui

sin la educacion que me dieron ustedes—gracias.

Omar Gonzalez

To my loved ones—as always I share my love, dedication, and dreams.

Chris Charlton

Foreword xv

About the Authors xvi

About the Technical Reviewer xviii

About the Cover Image Designer xix

Layout Conventions xx

PART 1 PLANNING THE RMX Chapter 1 Introduction to Flex 2 Applications 3

Chapter 2 Defining the Application: Introducing the RMX 19

Chapter 3 Planning the Application: Building the RMX 43

PART 2 BUILDING THE RMX CORE FUNCTIONS Chapter 4 Preparing to Get to Work 95

Chapter 5 Styling Flex 113

Chapter 6 Collecting and Working with Aggregated Content 145

Chapter 7 Secondary Navigation 165

Chapter 8 Forms and Validation 197

Chapter 9 User Communications 233

Chapter 10 Working with Video 261

Chapter 11 Advertising and Flex 299

CONTENTS AT A GLANCE

PART 3 BUILDING OUT NEW FEATURES

Chapter 12 Building the Blog 319

Chapter 13 Building the Jobs Board 337

Chapter 14 Building the Event Calendar 371

Chapter 15 Ideas for the Future: Extending the RMX 391

PART 4 SPECIAL TOPICS Chapter 16 RSLs and Persistent Framework Caching 419

Chapter 17 Search Engine Optimization for Flex 429

Chapter 18 Building an Audio Visualizer in Flex 443

Appendix The Evolving Flex Scene 457

Index 475

v

Foreword xv

About the Authors xvi

About the Technical Reviewer xviii

About the Cover Image Designer xix

Layout Conventions xx

PART 1 PLANNING THE RMX Chapter 1 Introduction to Flex 2 Applications 3

The Flash Platform and Web 2.0 3

Just what is this Web 2.0? 4

What’s Flash got to do with it? 5

Ubiquity 5

Reliability 5

Experience 6

Video 7

ActionScript 3 9

What is Flex? 10

To Flex or not to Flex 12

Is it an application? 13

Does it use components heavily? 14

How much custom skinning will be required? 14

Flexers are from Mars, Flashers are from Venus 14

Summary 16

Chapter 2 Defining the Application: Introducing the RMX 19

The amazing Adobe communities 20

The idea for the RMX is born 21

Defining the goals and functionality 22

Understanding the network 23

Independent application at an independent URL 23

Flexible feature set 26

CONTENTS

Core features 26

Event calendar 26

Membership communication 26

Forums 26

Blogs 27

Front pages 27

Video network 28

Jobs board 28

Social media functionality 28

Tagging 29

Commenting 29

Rating 30

Sharing 30

Flagging and moderation 31

RSS feed generation 31

Advertising 32

The tools for the task 32

A word on GNU GPL 32

Application platform 33

Flash and Ajax 33

LAMP 33

FlexTube.tv 34

Drupal 34

FFMPEG 35

OpenAds 35

EdgeCast 36

AMFPHP 36

Design and development tools 36

Adobe Illustrator, Fireworks, and Flash 36

Adobe Flex Builder 37

Flex-Ajax Bridge 37

OmniGraffle Professional 37

Firefox plug-ins 37

Project management tools 38

MS Project and Project Insight 38

Mantis 39

Subversion 39

Summary 40

Chapter 3 Planning the Application: Building the RMX 43

A note on complexity 43

Stages of planning 45

Defining the business requirements 46

Creating the wireframes 47

Authoring the project specification 51

CONTENTS

vii

Building the project plan 56

Planning the plan 56

Creating the project guide 59

Creating the project schedule 60

Getting into development 61

Designs 61

Technical specification 62

Development 62

Technical documentation 62

Testing and release 63

Testing 63

Release 64

Specific RMX planning considerations 66

General considerations 66

Web page vs application 66

Searching and filtering 68

The nature of the network 68

Central navigational elements 70

The control panels 70

The site 73

Planning parts of the RMX 78

The jobs board 79

The spec and wires 80

The event calendar 85

The spec and wires 86

The group control panel vs the network control panel 89

The spec and wires 89

Summary 92

PART 2 BUILDING THE RMX CORE FUNCTIONS Chapter 4 Preparing to Get to Work 95

Setting up the development environment 95

Flex Builder stand-alone or Eclipse plug-in installation 96

Source control, SVN, and Subclipse 96

PHPEclipse 97

Planning your application’s structure 97

Database design 97

Project structure and namespaces 97

New project template 99

The main application class 100

Data transfer objects 102

Final pointers before writing code 105

Variable and method naming 105

Commenting source control commits 106

Preparing code for documentation 107

Summary 110 CONTENTS

Chapter 5 Styling Flex 113

The Flex implementation of CSS 114

CSS 101: A primer 114

Tag selectors 117

Class selectors 119

Inline CSS styling 120

The <mx:Style/> tag 121

ActionScript-driven styling 122

The setStyle method 122

The Embed metadata tag 123

Asset libraries 124

Component-unique properties 126

Scale 9 formatting feature 129

Runtime CSS 135

The Flex Style Explorer 137

Styling considerations and the RMX 138

RMX styling obstacles 139

Hand cursors on Accordion headers 139

Custom ItemRenderers with rollover skins 141

Summary 143

Chapter 6 Collecting and Working with Aggregated Content 145

Data sources 145

Databases 146

MySQL 146

XML 147

XML structures and schemas 147

XML web feeds 147

Sharing outside the network 147

Sharing permalinks 147

Sharing by e-mail 148

Sharing and embedding video 152

Embedding with JavaScript 152

Embedding with XHTML 153

Using RSS 154

Attaching files to RSS feeds 158

XML namespaces and extensions 159

MRSS and syndicating to the Adobe Media Player 162

Summary 163

Chapter 7 Secondary Navigation 165

Pagination 165

Creating the database 167

Building the Products class 168

CONTENTS

ix

Building a Flex interface for Products.php 174

Time to import your classes 176

Handling navigation 178

Processing the results 179

Search integration 181

Upgrading the Flex application 184

Modularization 184

Enhancing the code 186

History management 188

Summary 194

Chapter 8 Forms and Validation 197

Data transfer objects 197

Why use DTOs? 197

Setting up a DTO 198

Setting up a form 199

The <mx:Form/> tag 199

The <mx:FormHeading/> tag 201

The <mx:FormItem/> tag 203

Handling user input 205

Collecting the user input 205

Validating user input 208

The validators array 208

Using the Validator classes 209

The EmailValidator 211

More validation 213

The restrict property 213

The maxChars property 214

Confirming the password and e-mail address 215

Submitting the form 221

Validating the form on submission 221

Managing remoting calls 222

Forms, PHP, and security 226

Security: Being careful with user-supplied content 226

Accepting text and dealing with form data 227

Accepting user-generated HTML 227

Accepting user-generated CSS 229

Summary 231

Chapter 9 User Communications 233

Building the communications control panel 233

In the beginning there was ActionScript 236

Overview of the ServiceUtil class 237

ActionScript interfaces 238

Class exploration 239

MXML development 243

Time to organize 245 CONTENTS

Layout design 246

Incorporating the data 250

Building the Communications class 252

Building the Services class 254

Extending to the inbox 256

Summary 259

Chapter 10 Working with Video 261

Video boot camp 261

Key video compression concepts 262

Codec 262

Bitrate 263

Framerate 263

Keyframe frequency 264

Constant vs variable bitrate 264

Cue points 265

Delivering Flash video 267

VideoDisplay component 267

Overview of basic properties/events 268

Playing a single static video 268

Adding a time played/total time display 270

Adding video controls 274

Pause/Play button 274

Stop button 276

Volume control 277

Additional functionality 279

Download progress bar 279

Playback progress bar 280

Video scrubber 281

Restricting the scrubber for progressive video players 283

The RMX video player controls 285

Playlists 287

Adding playlist control buttons 291

Restricting playlist controls during ad playback 293

Limitations of the VideoDisplay class 295

Summary 296

Chapter 11 Advertising and Flex 299

Why advertising matters 299

To open source or not to open source? 300

Flash and ads: Play nice, kids! 301

What about instream ads? 301

Our solution 302

Setting up OpenAds 302

Consuming OpenAds in Flex 307

CONTENTS

xi

f7670b088a34e6aa65a5685727db1ff4

Really, how powerful is this solution? 313

Beyond the banner 314

Advertising in AIR 315

Summary 315

PART 3 BUILDING OUT NEW FEATURES Chapter 12 Building the Blog 319

A blog? 319

Introducing the RMX blog 320

Installing Drupal 321

Building the blog 326

The Aggregator module 327

The Blog module 332

The Blog API module 332

Customizing the look and feel of Drupal 332

Summary 334

Chapter 13 Building the Jobs Board 337

Content management 337

Drupal modules 338

Generating services and Views 339

Generating Views in Drupal 340

Calling Views through the Services module 341

Learning more about the Drupal Services module 343

Preparing to start the jobs board 344

Advanced DTOs 344

Setting up custom events 348

Connecting to the Drupal services 350

The RMX base class 354

Setting up the jobs browser 355

Calling the jobs service 358

Setting up the list view 361

Handling the details pane 365

The jobs filters 367

Summary 369

Chapter 14 Building the Event Calendar 371

Dating (Web 2.0 style) 371

Examining the RMX calendar 371

Viewing events 372

Filtering events 372

Sharing events 374

Creating events 374 CONTENTS

Updating events 375

Deleting events 375

Building the interface 375

Have data, will travel 384

Back-end integration 386

Summary 389

Chapter 15 Ideas for the Future: Extending the RMX 391

The future 391

Data 393

Audio-to-text 393

Closed captioning in Flash 394

Creating a Flex component in Flash 398

Building the component 398

Using your Flash-generated SWC in Flex 402

Transcribing your audio 405

Robust user-generated folksonomy 405

Improved syndication controls 406

Advertising 406

Interstitials 407

Overlays 407

Hotspots 408

Bug-me-later ads 408

Money 409

Paid content 409

Payment models 409

Unit-based model 409

Subscription-based model 409

Points-based model 410

Royalties system 410

User group features 410

Physical library management 411

RSVP 411

Distribution 411

Planning for AIR 412

Planning for the Adobe Media Player 414

Summary 415

PART 4 SPECIAL TOPICS Chapter 16 RSLs and Persistent Framework Caching 419

Why are Flex SWF files big? 419

Runtime shared libraries 420

Persistent framework caching 420

CONTENTS

xiii

Setting up an application to use RSLs 421

Testing the caching 425

Custom SWCs and RSLs 426

Summary 426

Chapter 17 Search Engine Optimization for Flex 429

Using semantic markup to define content 430

Head content 430

Body content 432

XML 433

XML feeds 433

XML sitemaps 433

SWF metadata 435

Clean URLs 436

Deep linking 437

Using FXT 438

Summary 440

Chapter 18 Building an Audio Visualizer in Flex 443

AS2 vs AS3 443

Introducing the SoundMixer 448

Understanding the ByteArray 449

Design planning 449

The visualization 451

Summary 455

Appendix The Evolving Flex Scene 457

Designer/Developer workflow 457

Skin Importer 458

CSS outlines 459

Code enhancements 461

Refactoring 461

Class outlines 464

Code search 464

Multiple SDKs 465

Profiler 465

Compilation 465

Component and SDK enhancements 467

Deep linking 467

Runtime localization 469

Smaller SWFs 469

Flex and Flash integration 469

Flex + open source = no limits! 473

Summary 473

Index 475

CONTENTS

The world of Internet applications is changing Using Adobe Flex technologies, web applicationslook great, are accessible and portable, and can completely move the end-user experience wellbeyond the page response/request model popularized by HTML Best of all, the Flash Player isthe most widely distributed piece of software in the history of the Internet Never in history has

“the experience” been more important in terms of web applications Using Adobe Flash/Flextechnology, programmers can create state-of-the-art enterprise web applications that enableexperiences unlike anything else on the Web Numerous organizations throughout the worldhave discovered the benefits of Rich Internet Application technology to create better experi-ences for end users, which in turn leads to greater productivity and enhanced social interaction,

a primary goal of sites like YouTube and MySpace The Rich Media Exchange, the building ofwhich is detailed in this book, uses Rich Internet Application technology to foster a greatersense of community among Adobe User Groups worldwide

Getting started with Flex can be simple; MXML tags are easy to learn and provide tremendousfunctionality right out of the box Visual design mode and the host of components that shipwith the product make building your first Flex applications straightforward Taking this knowl-edge to the next level can be more difficult ActionScript has a steeper learning curve, but expe-rienced developers can pick up the basics with relative ease This book, unlike any other on themarket, details the internal workings of a large and complex application that utilizes best prac-tices You will see how a complex social networking site with a host of features, such as a calen-dar, communication among members, forums, and video, is made This book shows you how aFlex application should and should not be built Importantly, it will teach you when and how toutilize the existing Flex components and when to build your own The application shows how tocreate code that is scalable, manageable, and reusable

This book offers the reader an unparalleled insight into a complicated Flex project with a ber of moving parts Not only are Adobe Flex and the Flash Platform covered, but the bookoffers deep insight into the myriad details of planning, source control, documentation, and inte-grating with other technologies, including the server and Ajax This comprehensive look intosuch a large Flash-based application provides a window unlike anything else available on themarket Most importantly, the book details firsthand how Rich Internet Application technologycan enable organizations to better engage with end users and provide a great experience

num-James Talbot

Principle Instructor/Developer

Partner Readiness Adobe Systems Incorporated

xv

FOREWORD

R Blank is CTO of Almer/Blank, an Adobe Solution Partner based in Venice, California, that

spe-cializes in video and application development for the Flash Platform, for clients includingE! Entertainment, Live Nation, Microsoft, Apple, and IKEA For over 13 years, he has been aninteractive designer, developer, consultant, teacher, and author, specializing in the planning,development, and release of rich interfaces; R has specialized in Flash since 1999

R holds four Flash Certifications, was one of the first 50 certified Flash Developers in the world,

is an author for the Flash MX 2004 Designer Certification Exam, and is a frequent contributor to

the Adobe Edge newsletter In 2003, he founded and continues to manage LAFlash.org, a

com-munity of over 3,000 Flash industry professionals and home to three Adobe User Groups for theFlash Platform R also serves on the information technology faculty at the University of SouthernCalifornia Viterbi School of Engineering

Previously, R cofounded and served as director of product and design at Wildform, the makers

of the first video encoder for Flash, where he cocreated Flix, the first video encoder for Flash(now owned by On2) R has an MBA in entrepreneurship from the UCLA Anderson School ofManagement and a BA in history from Columbia University, and has studied at CambridgeUniversity (UK), the University of Salamanca (Spain), and the Nizhny Novgorod Institute ofForeign Languages (Russia)

Hasan Otuome is a senior application developer at Almer/Blank, where he can usually be found

developing Rich Internet Applications for the company’s clients He is an Adobe Flex championwho espouses creative uses and combinations of Flash, Flex, AIR, PHP, MySQL, and ColdFusionfor their benefits in creating unique user experiences

When not immersed in client development, Hasan can be found lending a helping hand to thedevelopment community at sites such as LAFlash.org, gotoAndLearn.com, thesourcecode.org,and ActionScript.org

ABOUT THE AUTHORS

Omar Gonzalez is a senior application developer at Almer/Blank who has been developing for

the Web since 1997 He has acquired a strong sense for developing accessible sites employingweb standards, open source projects, and frameworks like Drupal and CSS During the quick rise

of Flash, he began to incorporate the popular technology in the sites he worked on, addingFlash development as well as PHP and MySQL to his repertoire

Omar has developed Flash video applications for companies like eHarmony and has spoken atconferences like FITC on such topics as Flash video, Motion XML, and AIR Over the past twoyears he has been developing Flex applications, harnessing the power of Flash Platform tech-nology to create cutting-edge Rich Internet Applications Omar is on the resident faculty at theRich Media Institute, teaching topics in Flex, HTML/CSS, and web development, and he is anactive member of the LA Flash user groups

Chris Charlton is a software architect at Almer/Blank and an Adobe Flex champion He is a

CSS and ActionScript expert who successfully cannonballed into web development in the late

’90s and has been programming since childhood Always caught up with the latest in Flash,Dreamweaver, Fireworks, and XML, Chris authored premium articles for the largest Dreamweaver/Flash community, DMXzone (www.dmxzone.com), and produced WebDevDesign, a popular webdesign and development podcast featured on iTunes Somehow, Chris finds time to run anauthorized Adobe user group, LA AIR, focused around open source and Adobe technologies

As a community leader, Chris Charlton remains a resident faculty member of the Rich MediaInstitute and lends himself to speak at large industry events, like JobStock, NAB, andFITC Hollywood Brain cycles from Chris are always web standards, the Flash Platform, andaccessibility

xvii

Lar Drolet is a senior software engineer in Los Angeles where he develops Flex, AIR, and Flash

applications Lar is part of an ambitious team of developers and recently spoke at MAX and FITC

on Flex and AIR topics Not your typical engineer, Lar is an aspiring triathlete with a degree ineconomics and an MBA who will begin another graduate degree this spring

ABOUT THE TECHNICAL REVIEWER

Bruce Tang is a freelance web designer, visual programmer, and author from Hong Kong His

main creative interest is generating stunning visual effects using Flash or Processing

Bruce has been an avid Flash user since Flash 4, when he began using Flash to create games, websites, and other multimedia content After several years of ActionScripting, he found himselfincreasingly drawn toward visual programming and computational art He likes to integratemath and physics into his work, simulating 3D and other real-life experiences onscreen His firstFlash book was published in October 2005 Bruce’s folio, featuring Flash and Processing pieces,can be found at www.betaruce.com, and his blog at www.betaruce.com/blog

The cover image uses a high-resolution Henon phase diagram generated by Bruce withProcessing, which he feels is an ideal tool for such experiments Henon is a strange attractor cre-ated by iterating through some equations to calculate the coordinates of millions of points Thepoints are then plotted with an assigned color

To keep this book as clear and easy to follow as possible, the following text conventions areused throughout:

Important words or concepts are normally highlighted on the first appearance in bold type.

Code is presented in fixed-width font

New or changed code is normally presented in bold fixed-width font.

Menu commands are written in the form Menu ➤Submenu ➤Submenu

Where we want to draw your attention to something, we’ve highlighted it like this:

Sometimes code won’t fit on a single line in a book Where this happens, we use an arrow like

this: ➥.

This is a very, very long section of code that should be written ➥

all on the same line without a break

Ahem, don’t say I didn’t warn you.

LAYOUT CONVENTIONS

This book is about how we at Almer/Blank used Flex, along with other open source nologies like Drupal and OpenAds, to help create a great application, the Rich MediaExchange, or RMX Flex is a remarkable new way to build Internet-connected applica-tions; developers can now build Flash Platform projects of far larger scope and complex-ity than ever before So many books on Flex cover the basics—we want to take thisopportunity to extend that knowledge, to show you some of the techniques, code, andplanning that goes into building an advanced Flex application.

tech-We’ll get into the heavy technical stuff pretty soon, but in these first three chapters, wediscuss the state of Flash (where it’s at, what it offers, and what Flex has added to theequation) and then introduce you to the RMX, what it is, what tools we used to build it,and how we planned for the process

PLANNING THE RMX

Part 1

What an amazingly exciting time for Flash! Flash technologies are now way morepowerful than ever, and with Flex you now have a whole new way of creating contentfor the Flash Platform To get you started on the road to excellence in Flex applica-tions, this chapter gives you some background on the current state of the industry,what people are doing with Flash, and what Flex is adding to the mix.

Of course, the Internet isn’t about technology—it is about experiences Technology issimply the set of tools we developers use to create and deliver those experiences.Understanding how to create enjoyable, usable, and valuable Internet experiencesinvolves knowing how to integrate multiple technologies to achieve your specificgoals Different developers have different opinions on this, and any communityapplication must involve several technologies Increasingly, Flash technology isadding vitality, power, and depth to more and more aspects of these experiences

The Flash Platform and Web 2.0

The Flash Platform has evolved to a point of such power and flexibility that the ations now possible are awe-inspiring and available on an increasing variety ofdevices From 2001, when my colleagues and I at Wildform created Flix, the firstvideo encoder for Flash, we have come to the point where a business like YouTube,based entirely around Flash Platform video technology, is valued at over $1.5 billion,

cre-3

INTRODUCTION TO FLEX 2 APPLICATIONS

By R Blank

Chapter 1

and the entertainment industry has recognized the contributions of Adobe Flash video in the form of

an Emmy award

For those of us who have been working with Flash since the 1990s, through boom and bust and years

in the wilderness, it is so gratifying to see this amazing technology receive the attention and ment that it deserves And those new to the technology—like you reformed Java jockeys—are joining

invest-at a time of immense potential

But, in order to comprehend just what’s so exciting about the current scene, you should first

under-stand what the current scene is That scene is commonly referred to as Web 2.0.

Just what is this Web 2.0?

Web 2.0 is a term used so frequently now that it’s very easy to lose sight of what it actually means Infact, most people outside of Internet-related industries—and even many inside—don’t have a workingdefinition of Web 2.0

While there is no single accepted definition of Web 2.0, in my mind it refers to a general sense of aquantum leap in the quality of Internet-based experiences in the past few years In my opinion, Web2.0 began the day Netflix changed their ratings widget so that users didn’t have to refresh the page torate a video—they can now do so simply and quickly, inline in the page without updating the URL.That might sound like a minor change, but in practice it allowed a Netflix user such as myself to ratedozens of movies—even on a slow connection—in the time that it previously took to rate just a few,which meant that Netflix could provide better recommendations for me (and, of course, the friends Inow share those recommendations with will have deeper insight into my soul) The fact that I experi-enced the new ratings feature on a faster computer with a faster Internet connection meant that thevalue of the new ratings widget was that much greater That is a major leap in the value of the serviceNetflix provides to consumers and content providers

Of course, there really is nothing new, per se, represented by Web 2.0 But the various aspects thatconstitute Internet experiences—the software, the computers that run the software, and the connec-tions that network those computers—have all individually evolved to a point where, when combined,they enable experiences that are vastly more powerful, varied, specialized, enjoyable, and productive

In tangible terms, Web 2.0 manifests as video-sharing sites, wikis, blogs, and communities—technologiesthat enable user-generated content across a variety of media and forms—and RSS feeds, podcasts,and applications like Google Maps—technologies that improve user access to and interaction with thewide variety of media being generated Other features, such as permalinks (permanent, bookmarkableURLs for dynamic content), taxonomies (editorial tagging), and folksonomies (user-generated tag-ging), are the mortar holding this Web 2.0 together

But, in essence, Web 2.0 is just the proper execution of what we all wanted Web 1.0 to be—and whatmany, many Internet-focused startups failed while awaiting Indeed, in Tim Berners-Lee’s vision of theWeb, he foresaw “editors,” not “browsers,” that enabled users to edit and add to the content withwhich they interacted; however, the initial Internet technologies did not adequately support this vision(with certain notable exceptions—for instance, Amazon’s support for consumer reviews since itslaunch in 1995) It is interesting that Mr Berners-Lee doubts the existence of Web 2.0—perhapsbecause he sees it as the natural evolution of usage of the basic architecture he created

CHAPTER 1