Adobe Flash ActionScript 2.0 User guide

LEARNING ACTIONSCRIPT

™

2.0

IN FLASH

®

Learning ActionScript 2.0 in Adobe® Flash®

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3

Contents

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Intended audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

System requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Updating Flash XML files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

About the documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Additional resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Chapter 1: What’s New in Flash ActionScript . . . . . . . . . . . . . . . . 19

New in ActionScript 2.0 and Flash Player 9.x . . . . . . . . . . . . . . . . . . . . . 19

New in ActionScript 2.0 and

Flash Player 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Changes to security model for locally installed SWF files. . . . . . . . . . 28

Chapter 2: About ActionScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

What is ActionScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

About choosing between ActionScript 1.0 and ActionScript 2.0 . . . 33

Understanding ActionScript and Flash Player . . . . . . . . . . . . . . . . . . . 34

Chapter 3: Data and Data Types. . . . . . . . . . . . . . . . . . . . . . . . . . 35

About data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

About data types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

About variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Organizing data in objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72

About casting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74

Chapter 4: Syntax and Language Fundamentals . . . . . . . . . . . . . 77

About syntax, statements, and expressions . . . . . . . . . . . . . . . . . . . . . . .78

About dot syntax and target paths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

About language punctuators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

About constants and keywords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

About statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103

About arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

About operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

4Contents

Chapter 5: Functions and Methods . . . . . . . . . . . . . . . . . . . . . . . 163

About functions and methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

Understanding methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

Chapter 6: Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187

About object-oriented programming and Flash . . . . . . . . . . . . . . . . . . 188

Writing custom class files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

About working with custom classes in an application . . . . . . . . . . . . . 199

Example: Writing custom classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223

Example: Using custom class files in Flash . . . . . . . . . . . . . . . . . . . . . .236

Assigning a class to symbols in Flash . . . . . . . . . . . . . . . . . . . . . . . . . . .239

Compiling and exporting classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240

Understanding classes and scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243

About top-level and built-in classes . . . . . . . . . . . . . . . . . . . . . . . . . . . .246

About working with built-in classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256

Chapter 7: Inheritance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263

About inheritance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263

About writing subclasses in Flash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265

Using polymorphism in an application . . . . . . . . . . . . . . . . . . . . . . . . . . 271

Chapter 8: Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275

About interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .275

Creating interfaces as data types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280

Understanding inheritance and interfaces . . . . . . . . . . . . . . . . . . . . . . .282

Example: Using interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .283

Example: Creating a complex interface . . . . . . . . . . . . . . . . . . . . . . . . .285

Chapter 9: Handling Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291

About ActionScript and events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .292

Using event handler methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .293

Using event listeners. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .296

Using event listeners with components . . . . . . . . . . . . . . . . . . . . . . . . .298

Using button and movie clip event handlers . . . . . . . . . . . . . . . . . . . . 300

Broadcasting events from component instances. . . . . . . . . . . . . . . . 305

Creating movie clips with button states . . . . . . . . . . . . . . . . . . . . . . . . 305

Event handler scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306

Scope of the this keyword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310

Using the Delegate class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310

Contents 5

Chapter 10: Working with Movie Clips . . . . . . . . . . . . . . . . . . . . . 313

About controlling movie clips with ActionScript . . . . . . . . . . . . . . . . . .314

Calling multiple methods on a single movie clip . . . . . . . . . . . . . . . . . .316

Loading and unloading SWF files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .316

Changing movie clip position and appearance . . . . . . . . . . . . . . . . . . .319

Dragging movie clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320

Creating movie clips at runtime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .321

Adding parameters to dynamically created movie clips. . . . . . . . . . . 325

Managing movie clip depths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327

About caching and scrolling movie clips with ActionScript . . . . . . . 330

Using movie clips as masks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337

Handling movie clip events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339

Assigning a class to a movie clip symbol. . . . . . . . . . . . . . . . . . . . . . . . 339

Initializing class properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340

Chapter 11: Working with Text and Strings . . . . . . . . . . . . . . . . 343

About text fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344

About loading text and variables into text fields . . . . . . . . . . . . . . . . . 353

Using fonts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359

About font rendering and anti-alias text . . . . . . . . . . . . . . . . . . . . . . . . 367

About text layout and formatting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375

Formatting text with Cascading Style Sheet styles . . . . . . . . . . . . . . 382

Using HTML-formatted text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397

Example: Creating scrolling text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .410

About strings and the String class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411

Chapter 12: Animation, Filters, and Drawings . . . . . . . . . . . . . . 429

Scripting animation with ActionScript 2.0 . . . . . . . . . . . . . . . . . . . . . . 430

About bitmap caching, scrolling, and performance . . . . . . . . . . . . . 440

About the Tween and TransitionManager classes . . . . . . . . . . . . . . .441

Using filter effects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456

Working with filters using ActionScript . . . . . . . . . . . . . . . . . . . . . . . . 463

Manipulating filter effects with code . . . . . . . . . . . . . . . . . . . . . . . . . . . 489

Creating bitmaps with the BitmapData class . . . . . . . . . . . . . . . . . . . . 493

About blending modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 496

About operation order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498

Drawing with ActionScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499

Understanding scaling and slice guides . . . . . . . . . . . . . . . . . . . . . . . . .514

6Contents

Chapter 13: Creating Interaction with ActionScript . . . . . . . . . . 519

About events and interaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 520

Controlling SWF file playback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 520

Creating interactivity and visual effects . . . . . . . . . . . . . . . . . . . . . . . . 524

Creating runtime data bindings using ActionScript . . . . . . . . . . . . . . .537

Deconstructing a sample script . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .546

Chapter 14: Working with Images, Sound, and Video . . . . . . . 549

About loading and working with external media . . . . . . . . . . . . . . . . 550

Loading external SWF and image files. . . . . . . . . . . . . . . . . . . . . . . . . . 551

About loading and using external MP3 files . . . . . . . . . . . . . . . . . . . . 555

Assigning linkage to assets in the library . . . . . . . . . . . . . . . . . . . . . . . 559

About using FLV video. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560

About creating progress animations for media files. . . . . . . . . . . . . . 580

Chapter 15: Working with External Data . . . . . . . . . . . . . . . . . . 589

Sending and loading variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 590

Using HTTP to connect to server-side scripts . . . . . . . . . . . . . . . . . . 594

About file uploading and downloading . . . . . . . . . . . . . . . . . . . . . . . . . 600

About XML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 608

Sending messages to and from Flash Player . . . . . . . . . . . . . . . . . . . . 617

About the External API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 621

Chapter 16: Understanding Security . . . . . . . . . . . . . . . . . . . . . . 631

About compatibility with previous Flash Player security models . . . 631

About local file security and Flash Player. . . . . . . . . . . . . . . . . . . . . . . .633

Restricting networking APIs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .648

About domains, cross-domain security, and SWF files . . . . . . . . . . 650

Server-side policy files for permitting access to data . . . . . . . . . . . . .657

HTTP to HTTPS protocol access between SWF files . . . . . . . . . . . .662

Chapter 17: Best Practices and Coding Conventions for

ActionScript 2.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 665

Naming conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .666

Using comments in your code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 677

ActionScript coding conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .679

ActionScript and Flash Player optimization . . . . . . . . . . . . . . . . . . . . 695

Formatting ActionScript syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .697

Contents 7

Appendix A: Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . 707

Appendix B: Deprecated Flash 4 operators . . . . . . . . . . . . . . . . 713

Appendix C: Keyboard Keys and Key Code Values . . . . . . . . . . 715

Appendix D: Writing Scripts for Earlier Versions of Flash Player . .

721

About targeting earlier versions of Flash Player . . . . . . . . . . . . . . . . . . 721

Using Flash to create content for Flash Player 4 . . . . . . . . . . . . . . . . 722

Appendix E: Object-Oriented Programming with ActionScript 1.0.

725

About ActionScript 1.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 726

Creating a custom object in ActionScript 1.0 . . . . . . . . . . . . . . . . . . . . 728

Assigning methods to a custom object in ActionScript 1.0. . . . . . . . 729

Defining event handler methods in ActionScript 1.0 . . . . . . . . . . . . . 730

Creating inheritance in ActionScript 1.0 . . . . . . . . . . . . . . . . . . . . . . . . 732

Adding getter/setter properties to objects in ActionScript 1.0 . . . . . 734

Using Function object properties in ActionScript 1.0 . . . . . . . . . . . . . 735

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .737

8Contents

9

Introduction

Adobe Flash CS3 Professional is the professional standard authoring tool for producing high-

impact web experiences. ActionScript is the language you use to add interactivity to Flash

applications, whether your applications are simple animated SWF files or more complex rich

Internet applications. You don’t have to use ActionScript to use Flash, but if you want to

provide basic or complex user interactivity, work with objects other than those built into Flash

(such as buttons and movie clips), or otherwise turn a SWF file into a more robust user

experience, you’ll probably want to use ActionScript.

For more information, see the following topics:

Intended audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Updating Flash XML files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

System requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

About the documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Additional resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Intended audience

This manual assumes that you have already installed Flash and know how to use the user

interface.You should know how to place objects on the Stage and manipulate them in the

Flash authoring environment. If you have used a scripting language before, ActionScript will

seem familiar. But if you’re new to programming, ActionScript basics are easy to learn. You

can start with simple commands and build more complexity as you progress. You can add a lot

of interactivity to your files without having to learn (or write) a lot of code.

10 Introduction

System requirements

ActionScript 2.0 does not have any system requirements in addition to Flash.

Flash CS3 Professional introduces ActionScript 3.0. Flash Player 9 and ActionScript 3.0 are

the default publishing settings for Flash. This manual provides information on how to use

ActionScript 2.0 with Flash. You must change the publishing settings for your Flash files to

Flash Player 9 and ActionScript 2.0. If you do not change the default settings, explanations

and code samples in the documentation might not work correctly. If you develop applications

for earlier versions of Flash Player, see Appendix D, “Writing Scripts for Earlier Versions of

Flash Player,” on page 721.

Updating Flash XML files

It is important that you always have the latest Flash XML files installed. Adobe sometimes

introduces features in dot releases (minor releases) of Flash Player. When such a release is

available, you should update your version of Flash to get the latest XML files. Otherwise, the

Flash compiler might generate errors if you use new properties or methods that were

unavailable in the version of Flash Player that came with your Flash installation.

For example, Flash Player 7 (7.0.19.0) contained a new method for the System object,

System.security.loadPolicyFile. To access this method, you must use the Player

Updater installer to update all the Flash players that are installed with Flash. Otherwise, the

Flash compiler displays errors.

Remember that you can install a Player Updater that is one or more major versions ahead of

your version of Flash. By doing this, you will get the XML files that you need but shouldn’t

have any compiler errors when you publish to older versions of Flash Player. Sometimes new

methods or properties are available to older versions, and having the latest XML files

minimizes the compiler errors you get when you try to access older methods or properties.

About the documentation 11

About the documentation

This manual provides an overview of ActionScript syntax and information on how to use

ActionScript when working with different types of objects. For details on the syntax and usage

of every language element, see the ActionScript 2.0 Language Reference.

For more information, see the following topics:

■ “Learning ActionScript 2.0 book overview” on page 11

■ “About the sample files” on page 14

■ “Terms used in this document” on page 13

■ “Copy and paste code” on page 13

Learning ActionScript 2.0 book overview

The following list summarizes the contents of this manual:

■ Chapter 1, “What’s New in Flash ActionScript,” describes features that are new in

ActionScript, changes to the compiler and debugger, and the new programming model for

the ActionScript 2.0 language.

■ Chapter 2, “About ActionScript,” outlines what the ActionScript language is and details

how to choose between which version of ActionScript to use.

■ Chapter 3, “Data and Data Types,” describes the terminology and basic concepts about

data, data types, and variables. You use these concepts throughout the manual.

■ Chapter 4, “Syntax and Language Fundamentals,” describes the terminology and basic

concepts of the ActionScript language. You use these concepts throughout the manual.

■ Chapter 5, “Functions and Methods,” describes how to write different kinds of functions

and methods and how to use them in your application.

■ Chapter 6, “Classes,” describes how to create custom classes and objects in ActionScript.

This chapter also lists the built-in classes in ActionScript and provides a brief overview of

how you use them to access powerful features in ActionScript.

■ Chapter 7, “Inheritance,” describes inheritance in the ActionScript language and describes

how to extend built-in or custom classes.

■ Chapter 8, “Interfaces,” describes how to create and work with interfaces in ActionScript.

■ Chapter 9, “Handling Events,” describes a few different ways to handle events: event

handler methods, event listeners, and button and movie clip event handlers.

■ Chapter 10, “Working with Movie Clips,” describes movie clips and the ActionScript you

can use to control them.

12 Introduction

■ Chapter 11, “Working with Text and Strings,” describes the different ways you can

control text and strings in Flash and includes information on text formatting and

advanced anti-aliasing.

■ Chapter 12, “Animation, Filters, and Drawings,” describes how to create code-based

animation and images, add filters to objects, and draw using ActionScript.

■ Chapter 13, “Creating Interaction with ActionScript,” describes some simple ways in

which you can create more interactive applications, including controlling when SWF files

play, creating custom pointers, and creating sound controls.

■ Chapter 14, “Working with Images, Sound, and Video,” describes how to import external

media files, such as bitmap images, MP3 files, Flash Video (FLV) files, and other SWF

files, in your Flash applications. This chapter also provides an overview of how to work

with video in your applications, and how to create progress bar loading animations.

■ Chapter 15, “Working with External Data,” describes how to process data from external

sources using server- or client-side scripts in your applications. This chapter describes how

to integrate data with your applications.

■ Chapter 16, “Understanding Security,” explains security in Flash Player, as it pertains to

working with SWF files locally on your hard disk. This chapter also explains cross-domain

security issues, and how to load data from servers, or across domains.

■ Chapter 17, “Best Practices and Coding Conventions for ActionScript 2.0,” explains the

best practices for using Flash and writing ActionScript. This chapter also lists standardized

coding conventions, such as naming variables, and other conventions.

■ Appendix A, “Error Messages,” lists the error messages that the Flash compiler can

generate.

■ Appendix B, “Deprecated Flash 4 operators,” lists all the deprecated Flash 4 operators and

their associativity.

■ Appendix C, “Keyboard Keys and Key Code Values,” lists all the keys on a standard

keyboard and the corresponding ASCII key code values that are used to identify the keys

in ActionScript.

■ Appendix D, “Writing Scripts for Earlier Versions of Flash Player,” provides guidelines to

help you write scripts that are syntactically correct for the player version you are targeting.

■ Appendix E, “Object-Oriented Programming with ActionScript 1.0,” provides

information on using the ActionScript 1.0 object model to write scripts.

This manual explains how to use the ActionScript language. For information on the language

elements themselves, see the ActionScript 2.0 Language Reference.

About the documentation 13

Typographical conventions

This manual uses the following typographical conventions:

■ Code font indicates ActionScript code.

■ Bold code font, typically within a procedure, indicates code that you need to modify or

add to code you have already added to your FLA file. In some case, it might be used to

highlight code to look at.

■ Boldface text indicates data you need to type into the user interface, such as a filename or

instance name.

■ Italic text indicates a new term defined in the text that follows. In a file path, it might

indicate a value that should be replaced (for example, with a directory name on your own

hard disk).

Terms used in this document

The following terms are used in this manual:

■ You refers to the developer who is writing a script or application.

■ The user refers to the person who is running your scripts and applications.

■ Compile time is the time at which you publish, export, test, or debug your document.

■ Runtime is the time at which your script is running in Flash Player.

Copy and paste code

When you paste ActionScript from the Help panel into your FLA or ActionScript file, you

have to be careful about special characters. Special characters include special quotation marks

(also called curly quotation marks or smart quotation marks). These characters are not

interpreted by the ActionScript editor, so your code throws an error if you try to compile it

in Flash.

You can determine that your quotation mark characters are special characters if they do not

color-code correctly. That is, if all your strings do not change in color in the code editor, you

need to replace the special characters with regular straight quotation mark characters. If you

type a single or double quotation mark character directly into the ActionScript editor, you

always type a straight quotation mark character. The compiler (when you test or publish a

SWF file) throws an error and lets you know if there are the wrong kind (special quotation

marks or curly quotation marks) of characters in your code.

NOTE

You might also encounter special quotation marks if you paste ActionScript from other

locations, such as a web page or a Microsoft Word document.

14 Introduction

Be cautious of proper line breaks when you copy and paste code. If you paste your code from

some locations, the line of code might break in an improper location. Make sure that the color

coding of your syntax is correct in the ActionScript editor if you think line breaks might be a

problem. You might want to compare your code in the Actions panel to that in the Help panel

to see if it matches. Try turning on Word Wrap in the ActionScript editor to help solve

surplus line breaks in your code (select View > Word Wrap in the Script window, or Word

Wrap from the Actions panel pop-up menu.)

Additional resources

In addition to this manual about ActionScript, there are manuals on other Flash topics, such

as components and Adobe Flash Lite. You can access each manual in the Help panel (Help >

Flash Help), by viewing the default Table of Contents. Click the Clear button to see each

manual that’s available; for more information, see “Where to find documentation on other

subjects” on page 17.

For more information about other available resources, see the following topics:

■ “About the sample files” on page 14

■ “Where to find PDF files or printed documentation” on page 15

■ “About LiveDocs” on page 15

■ “Additional online resources” on page 16

■ “Where to find documentation on other subjects” on page 17

About the sample files

There are numerous ActionScript-based sample files available that install with Flash. These

sample files show you how code works in a FLA file; this is often a useful learning tool. The

chapters in this manual often reference these files, but we recommend that you also check out

the sample files folder on your hard disk.

The sample files include application FLA files that use common Flash functionality installed

with Flash. These applications were designed to introduce new Flash developers to the

capabilities of Flash applications, as well as show advanced developers how Flash features work

in context.

Additional resources 15

For samples of ActionScript-focused sample source files, see the Flash Samples page at

www.adobe.com/go/learn_fl_samples. Download and decompress the Samples zip file and

navigate to the ActionScript2.0 folder to access the samples. For components-focused sample

files, navigate to the ComponentsAS2 folder.

Where to find PDF files or printed documentation

If you prefer to read documentation in printed format, the PDF versions of each Help manual

are available for downloading. Go to www.adobe.com/support/documentation/ and select the

product you’re interested in. You can view or download the PDF or link to the LiveDocs

version of the manual.

Often, you can also purchase printed documentation. For updated information, go to the

Documentation support site.

About LiveDocs

You can access documentation at the LiveDocs website, in addition to accessing it from the

Help panel. The LiveDocs website contains all of the Flash Help pages and might contain

comments that clarify, update, or correct parts of the documentation. Click View Comments

on LiveDocs at the bottom of a page in the Help panel to display the equivalent page on the

LiveDocs website. Go to http://livedocs.macromedia.com to see a list of all of the available

documentation in the LiveDocs format.

Technical writers monitor the LiveDocs website. One of the advantages of LiveDocs is seeing

comments that clarify the documentation or correct any errata or issues that arise after a

software release. LiveDocs is not the place to make help requests, such as asking questions

about your code that doesn’t work, comment on problems with software or installation, or ask

how to create something with Flash. It is the correct place to provide feedback about the

documentation (for example, you notice a sentence or paragraph that could be clarified).

When you click the button to add a comment on LiveDocs, there are several points about the

kinds of comments that are acceptable on the system. Please read these guidelines closely, or

your comment might be removed from the website.

If you have a question about Flash, please ask it on the Adobe web forums: www.adobe.com/

support/forums/. The web forums are the best place to ask questions, because there are many

Adobe employees, Team Adobe volunteers, Adobe user group managers and members, and

even technical writers who monitor these forums.

16 Introduction

Engineers do not monitor the LiveDocs system but do monitor the Flash wish list. If you

think you have found a bug in the software, or you would like to request an enhancement to

Flash, please fill out the wishform at www.adobe.com/go/wish. If you report your bug or

enhancement request on LiveDocs, it will not be officially added to the bug database. You

must use the wishform instead, if you want an engineer to see your bug or request.

Remember to be careful about special characters and line breaks when you paste from the

web, including LiveDocs. Adobe has made every effort to remove all special characters from

code samples, but if you have problems pasting code, see “Copy and paste code” on page 13.

Additional online resources

There are several resources online that offer a wealth of instruction, help, and guidance to help

you learn Flash. Check the following websites often for updates:

The Adobe Developer Center website (www.adobe.com/devnet) is updated regularly with

the latest information on Flash, plus advice from expert users, advanced topics, examples, tips,

tutorials (including multipart tutorials), and other updates. Check the website often for the

latest news on Flash and how to get the most out of the program.

The Adobe Flash Support Center (www.adobe.com/support/flash) provides TechNotes,

documentation updates, and links to additional resources in the Flash community.

The Adobe Weblogs website (http://weblogs.macromedia.com) provides a list of both

Adobe employee and community weblogs (also known as blogs).

The Adobe web forums (http://www.adobe.com/support/forums/) provides numerous

forums for asking specific questions about Flash, your applications, or the ActionScript

language. The forums are monitored by Team Adobe volunteers and often visited by Adobe

employees as well. If you’re not sure where to go, or how to solve a problem, a Flash forum is

a good place to start.

The Adobe Community website (www.adobe.com/community) regularly hosts a series of live

presentations on a variety of topics by Adobe employees or community members. Check the

website often for updates.

Additional resources 17

Where to find documentation on other subjects

The following manuals offer additional information on subjects commonly associated with

ActionScript 2.0:

■ For information about the elements that compose the ActionScript language, see the

ActionScript 2.0 Language Reference.

■ For information about working in the Flash authoring environment, see How to Use Help.

■ For information about working with components, see Using ActionScript 2.0 Components.

18 Introduction

19

1

CHAPTER 1

What’s New in Flash

ActionScript

Adobe Flash CS3 Professional provides several enhancements that make it easy for you to

write robust scripts using the ActionScript language. The new features, which are discussed in

this chapter, include new language elements (see “Additions to the ActionScript language in

Flash Player 8” on page 22), improved editing tools (see “ActionScript editing changes”

on page 27), changes to the security model, and other ActionScript-related improvements to

the authoring tool.

For more information, see the following topics:

New in ActionScript 2.0 and Flash Player 9.x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

New in ActionScript 2.0 and Flash Player 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Changes to security model for locally installed SWF files. . . . . . . . . . . . . . . . . . . . . . 28

New in ActionScript 2.0 and Flash Player

9.x

Flash Player 9.x allows a user to switch the Flash Player into and out of fullscreen mode. The

following items support this new feature:

■ Stage.displayState property

■ Stage.onFullScreen event handler

■ allowFullScreen parameter in the object and embed HTML tags

For more information, see ActionScript 2.0 Language Reference.

Flash Player 9.x also introduces a new FileReference event,

onUploadCompleteData. This

event can be invoked after a server receives a successful upload. For more information on this

new item, see ActionScript 2.0 Language Reference.

20 What’s New in Flash ActionScript

New in ActionScript 2.0 and

Flash Player 8

The ActionScript language has grown and developed since its introduction several years ago.

With each new release of Flash, additional keywords, objects, methods, and other language

elements were added to ActionScript. There are also ActionScript-related improvements to

the Flash 8 authoring environments. Flash Basic 8 and Flash Professional 8 introduced several

new language elements for expressive features, such as filters and blending modes, and

application development, such as JavaScript integration (ExternalInterface) and file input and

output (FileReference and FileReferenceList).

This section provides an overview of the ActionScript language elements and classes that are

new or changed in Flash 8 and ActionScript-related improvements to the authoring tool. For

a list of specific additions to ActionScript 2.0, see “Additions to the ActionScript language in

Flash Player 8” on page 22. To use any of the new language elements in your scripts, you must

target Flash Player 8 when you publish your documents.

The following features were added to both Flash Basic 8 and Flash Professional 8 (unless

noted otherwise):

■ ActionScript editor enhancements let you show hidden characters in your scripts. For

more information, see “Display hidden characters” in Using Flash.

■ Debug options are now available in the Script window, as well as the Actions panel, for

ActionScript files.

■ The Configuration directory that includes XML files and Class files is reorganized. See

“Configuration folders installed with Flash” in Using Flash for details.

■ You can set a preference to reload modified script files when working on an application,

which helps you avoid working with older versions of script files, and overwriting newer

script files. For more information, see “Set ActionScript preferences” in Using Flash.

■ The Script window feature is available in Flash. That means you can now create an

ActionScript file in either program.

■ Script Assist (similar to Normal Mode in earlier editions of Flash) helps you code without

needing to understand syntax. For more information on Script Assist, see “About Script

Assist mode” in Using Flash.

■ You can load new kinds of image files at runtime, which include progressive JPEG images,

and non-animated GIF and PNG files. If you load an animated file, the first frame of the

animation appears.

■ You can assign linkage identifiers to bitmap and sound files stored in the Library, which

means that you can attach images to the Stage or work with these assets in shared libraries.

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Adobe Flash ActionScript 2.0 User guide

Adobe Flash ActionScript 2.0 User guide

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