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Contents PART 1: OVERVIEW OF ACTIONSCRIPT PROGRAMMING About This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 Using this manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Accessing ActionScript documentation . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Developer Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Chapter 1: Introduction to ActionScript 3.0 . . . . . . . . . . . . . . . . . . 15 About ActionScript. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Advantages of ActionScript 3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 What's new in ActionScript 3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Compatibility with previous versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Chapter 2: Getting Started with ActionScript . . . . . . . . . . . . . . . 23 The basic ActionScript development process . . . . . . . . . . . . . . . . . . . . 23 Options for organizing your code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Example: Creating a basic application . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Chapter 3: ActionScript Language and Syntax . . . . . . . . . . . . . 35 Language overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Objects and classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37 Packages and namespaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Variables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 Data types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Conditionals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 Looping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Chapter 4: Object-Oriented Programming in ActionScript . . . . 107 Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126 Inheritance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130 3 Advanced topics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Example: GeometricShapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 Chapter 5: Display Programming . . . . . . . . . . . . . . . . . . . . . . . . . 159 Understanding the display architecture . . . . . . . . . . . . . . . . . . . . . . . . . 160 Working with display objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Basics for working with the core display classes . . . . . . . . . . . . . . . . . 176 Example: SpriteArranger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187 PART 2: CORE ACTIONSCRIPT 3.0 DATA TYPES AND CLASSES Chapter 6: Working with Dates and Times . . . . . . . . . . . . . . . . . 197 Managing calendar dates and times . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Controlling time intervals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 Example: Simple analog clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 Chapter 7: Working with Strings . . . . . . . . . . . . . . . . . . . . . . . . 209 Creating strings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 The length property. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211 Working with characters in strings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211 Comparing strings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212 Obtaining string representations of other objects . . . . . . . . . . . . . . . . 213 Concatenating strings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 Finding substrings and patterns in strings . . . . . . . . . . . . . . . . . . . . . . . 214 Converting strings between uppercase and lowercase . . . . . . . . . . . 219 Example: ASCII Art . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 Chapter 8: Working with Arrays . . . . . . . . . . . . . . . . . . . . . . . . . 227 Indexed arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 Associative arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236 Multidimensional arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 Cloning arrays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243 Advanced Topics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243 Example: PlayList . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Chapter 9: Handling Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255 Types of errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256 Error handling in ActionScript 3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258 Working with the debugger version of Flash Player . . . . . . . . . . . . . 260 4 Contents Handling synchronous errors in an application . . . . . . . . . . . . . . . . . . .261 Creating custom error classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 Responding to error events and status . . . . . . . . . . . . . . . . . . . . . . . . . 267 Comparing the Error classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 Example: CustomErrors application. . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 Chapter 10: Using Regular Expressions . . . . . . . . . . . . . . . . . . . 285 Introduction to Regular Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 Regular expression syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 Methods for using regular expressions with strings . . . . . . . . . . . . . . 303 Example: A Wiki parser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304 Chapter 11: Working with XML . . . . . . . . . . . . . . . . . . . . . . . . . . . 311 A quick introduction to XML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .312 The E4X approach to XML processing . . . . . . . . . . . . . . . . . . . . . . . . . .313 XML objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .315 XMLList objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317 Initializing XML variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .319 Assembling and transforming XML objects . . . . . . . . . . . . . . . . . . . . . 320 Traversing XML structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322 Using XML namespaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327 XML type conversion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328 Reading external XML documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330 Example: Loading RSS data from the Internet . . . . . . . . . . . . . . . . . . 330 PART 3: FLASH PLAYER APIS Chapter 12: Flash Player API Overview . . . . . . . . . . . . . . . . . . . 337 flash.accessibility package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338 flash.display package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338 flash.errors package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339 flash.events package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339 flash.external package. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340 flash.filters package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340 flash.geom package. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...