Chapter 1. Flex and ActionScript Basics

A Flex application consists primarily of code written in two different languages: ActionScript and MXML. In its 3.0 incarnation, ActionScript went from a prototype-based scripting language to a fully object-oriented, strictly typed language. MXML is a markup language that will feel comfortable to anyone who has spent time working with Hypertext Markup Language (HTML), Extensible Markup Language (XML), or a host of newer markup-based languages.

Many newcomers to Flex wonder how MXML and ActionScript relate to one another. The MXML compiler (mxmlc), after parsing through the different idioms, translates them into the same objects, so that this: