User Guide

18 About Components
Version 2 components are written in ActionScript 2.0. Each component is a class and each
class is in an ActionScript package. For example, a radio button component is an instance of
the RadioButton class whose package name is mx.controls. For more information about
packages, see “About packages” in Learning ActionScript 2.0 in Flash.
Most UI components built with version 2 of the Macromedia Component Architecture are
subclasses of the UIObject and UIComponent classes and inherit all properties, methods, and
events from those classes. Many components are also subclasses of other components. The
inheritance path of each component is indicated in its entry in the Components Language
Reference.
All components also use the same event model, CSS-based styles, and built-in themes and
skinning mechanisms. For more information on styles and skinning, see Chapter 5,
“Customizing Components,” on page 81. For more information on event handling, see
Chapter 3, “Working with Components,” on page 49.
For a detailed explanation of the version 2 component architecture, see Chapter 6, “Creating
Components,” on page 125.
Version 2 component features
This section outlines the features of version 2 components (compared to version 1
components) from the perspective of a developer using components to build Flash
applications. For detailed information about the differences between the version 1 and version
2 architectures for building components, see Chapter 6, “Creating Components,” on
page 125.
The Component inspector allows you to change component parameters while authoring in
Macromedia Flash and Macromedia Dreamweaver. (See “Setting component parameters”
on page 55.)
The listener event model allows listeners to handle events. (See Chapter 4, “Handling
Component Events,” on page 63.) Flash doesn’t have a
clickHandler parameter in the
Property inspector, as there was in Flash MX; you must write ActionScript code to
handle events.
Skin properties let you load individual skins (for example, up and down arrows or the check
for a check box) at runtime. (See “About skinning components” on page 96.)
CSS-based styles allow you to create a consistent look and feel across applications. (See
“Using styles to customize component color and text” on page 82.)
NOTE
The class hierarchy is also available as a FlashPaper file in the installation location: Flash
8\Samples and Tutorials\Samples\Components\arch_diagram.swf.