Mihai Corlan
Alin Achim


13 December 2010

Prerequisite knowledge
Required Products
Sample files
Knowledge of Flex 3 and Flex 4.

Flex 4 (Download trial)
Flash Builder (Download trial)

Upgrading Flex 3 applications to Flex 4 SDK
User level

This technical guide is for developers who are upgrading to Flex 4 SDK.  By upgrading, we mean "beginning to use the new version of Flex." It focuses on the material you’ll want to know as you begin to use this new version of Flex.  Though you will likely find information in this guide that you can use if you are migrating a Flex project, that is, to move and update a project from one version of Flex to the next, there are other documents that are more focused on moving and updating a project from earlier versions of Flex to Flex 4 (see Chapter 4 of the Adobe Flex 4 Features and Migration Guide, for example).  Also, see the "Migrating Flex 3 Projects to Flex 4" section of this document for an overview of the migration process.
While it is impossible to cover all the aspects of any nontrivial framework or language in only 40 pages, we are confident that after reading this document you’ll manage to find your way on Flex 4 projects. On the web there are many interesting articles on Flex and there is extensive documentation on the Adobe website. This document is not intended to duplicate that content.  Instead, we have strived to keep it focused on what you need to know, so you have enough information to get started and you know where to look for more.
Spark Component Model