Adobe Flex Builder lets you create, manage, package, and distribute projects for building web and desktop applica- tions. When you generate shared component library (SWC) files, you can share components and other resources between applications or with other developers. You can also work with different versions of the Adobe Flex SDK directly in Flex Builder ...

Flex Builder includes a variety of media to help you learn the program quickly and become proficient in creating Flex applications. The Flex Builder help system includes several topics that help you learn about Flex Builder, Flex, MXML, and ActionScript. (All documentation is available online in LiveDocs format and Adobe PDF.) You can also consult other online resources as you learn how to build Flex applications.

You can select the documentation set that you want to search. For example, if you have other Eclipse plug-ins installed, the list of available documentation in help can be quite long. To search only the Flex documentation, you can define the scope of the search to eliminate unwanted search results.

The Help viewer in Flex Builder does not support changing the font size used to display Help documentation. However, you can select to run Help in a web browser and control the font size using the browserâ s font settings.

Flex Builder is a collection of Eclipse plug-ins that provide the tools you need to create Flex and ActionScript 3.0 applications. The Eclipse plug-in framework allows plug-ins to expose extension points, which can be used to extend the features and capabilities of the tool. For more information, see Adobe Flex Builder 3 Extensibility API Reference in Help.
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Source: livedocs.adobe.com