While you likely know what ActionScript is and are eager to begin working with the new version, a brief overview of its development will give you some insight into its use—particularly 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, and will cover:
What Is ActionScript 3.0? It’s to be expected that a new version of ActionScript will bring with it new features. However, this version has been written anew from the ground up and is even handled separately from previous versions of ActionScript at runtime. This intentional splintering of Flash Player affords significant performance increases, but also brings with it limitations as to how multiple versions of ActionScript interact.
The Flash Platform. At the time of this writing, ActionScript 3.0 is the internal programming language of Flex and AIR (the Adobe Integrated Runtime application). Differences in compiling and environment-specific attributes prevent every file written in ActionScript 3.0 from working in every aspect of the Flash Platform, but the fundamentals—indeed the bulk—of the language is the same throughout.
Procedural Versus Object-Oriented Programming. A great deal of attention has been focused on the object-oriented programming (OOP) capabilities of ActionScript 3.0, and the power and robustness of the language really shine in this area. However, you’ll be happy to learn that a move to ActionScript 3.0 doesn’t mean that you must become an expert at OOP. It is still possible to use a structured collection of functions, which characterize procedural programming, to author ActionScript 3.0 projects. In addition, using Flash CS3, it is still possible to code in the timeline, rather than coding exclusively with external classes. If you prefer object-oriented programming, enhancements to ActionScript 3.0’s OOP infrastructure make it more robust and bring it more in line with the features of other important, OOP-based languages (such as Java) and make moving between such languages a bit easier.
