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Part Number ZFL70M400 Acknowledgments Director: Erick Vera Project Management: Stephanie Gowin, Barbara Nelson Writing: Jody Bleyle, Mary Burger, Kim Diezel, Stephanie Gowin, Dan Harris, Barbara Herbert, Barbara Nelson, Shirley Ong, 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, Jeff Harmon First Edition: Septermber 2003 Macromedia, Inc. 600 Townsend St. San Francisco, CA 94103 CONTENTS INTRODUCTION: Getting Started with ActionScript ....................... 9 Intended audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 System requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Using the documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Typographical conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Terms used in this document. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Additional resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 PART I: Welcome to ActionScript CHAPTER 1: What's New in Flash MX 2004 ActionScript. . . . . . . . . . . . . . . . . . 13 13 14 15 21 22 22 New and changed language elements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . New security model and legacy SWF files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Porting existing scripts to Flash Player 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ActionScript editor changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Debugging changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . New object-oriented programming model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHAPTER 2: ActionScript Basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 25 26 26 29 34 37 40 45 50 51 51 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 . . . . . . . . . . . . . . . . . . . . . . . Specifying an object's path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using built-in functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 CHAPTER 3: Writing and Debugging Scripts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Controlling when ActionScript runs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Using the Actions panel and Script window. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Using the ActionScript editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Debugging your scripts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 Using the Output panel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Updating Flash Player for testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 PART II: Handling Events and Creating Interaction CHAPTER 4: Handling Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Using event handler methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Using event listeners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 Using button and movie clip event handlers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 Creating movie clips with button states . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 Event handler scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 Scope of the "this" keyword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 CHAPTER 5: Creating Interaction with ActionScript . . . . . . . . . . . . . . . . . . . . . . 91 About events and interaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Controlling SWF file playback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Creating interactivity and visual effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Deconstructing a sample script . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 PART III: Working with Objects and Classes CHAPTER 6: Using the Built-In Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 About classes and instances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Overview of built-in classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 CHAPTER 7: Working with Movie Clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 About controlling movie clips with ActionScript . . . . . . . . . . . . . . . . . . . . . . . . . 121 Calling multiple methods on a single movie clip . . . . . . . . . . . . . . . . . . . . . . . . . 122 Loading and unloading additional SWF files . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Specifying a root Timeline for loaded SWF files . . . . . . . . . . . . . . . . . . . . . . . . . 123 Loading JPEG files into movie clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 Changing movie clip position and appearance . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Dragging movie clips. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Creating movie clips at runtime. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 Adding parameters to dynamically created movie clips . . . . . . . . . . . . . . . . . . . . 128 Managing movie clip depths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 Drawing shapes with ActionScript. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Using movie clips as masks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 4 Contents Handling movie clip events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 Assigning a class to a movie clip symbol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Initializing class properties. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 CHAPTER 8: Working with Text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 135 137 137 139 147 153 Using the TextField class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating text fields at runtime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using the TextFormat class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Formatting text with Cascading Style Sheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using HTML-formatted text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating scrolling text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHAPTER 9: Creating Classes with ActionScript 2.0 . . . . . . . . . . . . . . . . . . . . 155 156 157 161 165 167 169 171 171 172 173 174 Principles of object-oriented programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using classes: a simple example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating and using classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instance and class members . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating and using interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Understanding the classpath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Importing classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Implicit get/set methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating dynamic classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . How classes are compiled and exported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PART IV: Working with External Data and Media CHAPTER 10: Working with External Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Sending and loading variables to and from a remote source . . . . . . ...