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Part Number ZFE15M200 Acknowledgments Project Management: Barbara Herbert, Stephen Gilson Writing: Jody Bleyle, Mary Burger, Kim Diezel, Stephen Gilson, Stephanie Gowin, Dan Harris, Barbara Herbert, Matt Horn, Barbara Nelson, Shirley Ong, Michael Peterson, Tim Statler Managing Editor: Rosana Francescato Editing: Linda Adler, Mary Ferguson, Mary Kraemer, Noreen Maher, Antonio Padial, Lisa Stanziano, Anne Szabla Production Management: Patrice O'Neill Media Design and Production: Adam Barnett, Christopher Basmajian, Aaron Begley, John Francis Second Edition: November 2004 Macromedia, Inc. 600 Townsend St. San Francisco, CA 94103 CONTENTS INTRODUCTION: Getting Started with ActionScript ....................... 5 5 5 6 6 6 Intended audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using the documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Typographical conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Terms used in this document. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Additional resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PART I: Welcome to ActionScript CHAPTER 1: ActionScript Basics ...................................... 9 10 10 11 13 18 23 27 31 39 41 41 Differences between ActionScript and JavaScript . . . . . . . . . . . . . . . . . . . . . . . . . Unicode support for ActionScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . About data types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Assigning data types to elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . About variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using operators to manipulate values in expressions . . . . . . . . . . . . . . . . . . . . . . . Using condition statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using built-in functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHAPTER 2: Creating Custom Classes with ActionScript 2.0 . . . . . . . . . . . . . . . 45 Principles of object-oriented programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Using classes: a simple example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Creating and using classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 Creating dynamic classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Using packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Creating and using interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Instance and class members . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Implicit getter/setter methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Understanding the classpath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Importing classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 3 CHAPTER 3: Working with External Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Sending and loading variables to and from a remote source . . . . . . . . . . . . . . . . . . 67 Sending messages to and from Flash Player . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 PART II: Reference CHAPTER 4: About the ActionScript Language Reference . . . . . . . . . . . . . . . . . 77 Sample entry for most ActionScript elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Sample entry for classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 CHAPTER 5: ActionScript Core Language Elements. CHAPTER 6: ActionScript Core Classes. CHAPTER 7: ActionScript for Flash . . . . . . . . . . . . . . . . . . . . . 80 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 490 . . . . . . . . . . . . . . . . . . . . . . . . . . 809 . . . . . . . . . . . . . . . . . . . . 811 APPENDIX A: Deprecated Flash 4 operators . APPENDIX B: Keyboard Keys and Key Code Values . Letters A to Z and standard numbers 0 to 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 811 Keys on the numeric keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 813 Function keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 813 Other keys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 814 INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 817 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 823 INDEX OF LANGUAGE ELEMENTS. 4 Contents INTRODUCTION Getting Started with ActionScript Macromedia Flex developers can use ActionScript to extend the functionality of their Flex applications. ActionScript is an ECMAScript-based language that provides support for objectoriented development. You are not required to use ActionScript to use Flex, but it provides flow control and object manipulation features that are not available in strict MXML. Intended audience This manual assumes that you already installed Macromedia Flex and know how to use it. If you have written programs before, ActionScript will seem familiar. But if you're new to programming, ActionScript isn't hard to learn. It's easy to start with simple commands and build more complexity as you progress. Using the documentation This manual provides an overview of ActionScript syntax, information on how to use ActionScript when working with different types of objects, and details on the syntax and usage of every language element. The following list summarizes the contents of this manual. · Chapter 1, "ActionScript Basics," on page 9 describes the terminology and basic concepts used in the rest of the manual. · Chapter 2, "Creating Custom Classes with ActionScript 2.0," on page 45 describes how to create custom classes and objects for manipulating data in your applications. · Chapter 3, "Working with External Data," on page 67 describes how to process data from external sources using server- or client-side scripts in your applications. · Chapter 4, "About the ActionScript Language Reference," on page 77 provides an overview of the second part of the manual, which describes the elements that comprise the ActionScript language. · Chapter 5, "ActionScript Core Language Elements," on page 80 explains all of the elements of the ActionScript language that are not related to a particular class or to a particular Macromedia product. · Chapter 6, "ActionScript Core Classes," on page 232 documents all of the classes of the ActionScript language that are not related to a particular Macromedia product. 5 · Chapter 7, "ActionScript for Flash," on page 490 describe functions, properties, and classes of Macromedia Flash Player that you can use in a Macromedia Flex application, if appropriate. · Appendix A, "Deprecated Flash 4 operators," on page 809 lists all the ActionScript operators and their associativity. · Appendix B, "Keyboard Keys and Key Code Values," on page 811 lists all the keys on a standard keyboard and the corresponding ASCII key code values that are used to identify the keys in ActionScript. Typographical conventions The following typographical conventions are used in this manual: · · Code font indicates Code font italic ActionScript code. indicates an element, such as an ActionScript parameter or object name, that you replace with your own text when writing a script. 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. ActionScript terms such as method and object are defined in Chapter 1, "ActionScript Basics," on page 9. Additional resources Specific documentation about Macromedia Flash and related products is available separately. · For information about creating communication applications with Flash Communication Server, see Developing Communications Applications and Managing Flash Communication Server. · For information about building Flex applications, see Developing Flex Applications. The Macromedia DevNet website (www.macromedia.com/devnet) is updated regularly with the latest information on Flash, plus advice from expert users, advanced topics, examples, tips, and other updates. Check the website often for the latest news on Flash and how to get the most out of the program. The Macromedia Flash Support Center (www.macromedia.com/support/flash) provides TechNotes, documentation updates, and links to additional resources in the Flash community. 6 Introduction: Getting Started with ActionScript PART I Welcome to ActionScript PART I This part includes information on using the ActionScript language. For information on the classes and language elements you can use in your scripts, see Part II, "Reference." Chapter 1: ActionScript Basics . . . . . . ...