Chapter 1. What Is ActionScript?
IN THIS CHAPTER
What’s New in ActionScript 3.0?
The Flash Platform
Procedural Versus Object-Oriented Programming
The Document Class
Legacy Code Compatibility
Hello World
What’s Next?
While you likely know that ActionScript is the main scripting language of the Flash Platform, and you’re no doubt eager to begin working with the new version, a brief overview of its development will give you some insight into its use—particularly as related to Flash Player and how it handles different versions of ActionScript. This brief introductory chapter will give you a quick look at where ActionScript 3.0 fits into your workflow.
Before we get started, it might help to understand how you get from ActionScript code to a finished file that you can put into a website. If this isn’t news to you, bear with us for just a paragraph or two.
When you publish a Flash file—using Flash Professional’s File✓Publish or Control✓Test Movie—all of the internal graphics and other assets used in your movie, as well as all of the ActionScript code, are compiled into a final file format called a SWF (pronounced “swiff” or “S-W-F”). That is, a part of your Flash Platform application of choice (such as Flash Professional) contains software called the compiler. This software converts all of your human-readable scripts into an optimized, machine-readable format. It combines that code with your assets into a single SWF file that Flash Player can decode and play back for all to see.
Although your SWF ...