Flex Release Notes

Flex Builder 2 Release Notes (2.0.1 Update)

Welcome to Adobe® Flex™ Builder™ 2, the next-generation IDE for Flex developers. Flex Builder 2 is built on Eclipse™ and represents a major improvement over the previous version.

New: The 2.0.1 update includes support for Macintosh OS X..

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What's new

The following list describes some of the major new features and changes for Flex Builder 2. For more information on new features, samples, and examples, see the Flex Developer Center:

  • Powerful coding tools - Develop rich applications by using a powerful Eclipse based IDE that includes editors for MXML, ActionScript, and CSS, providing syntax coloring, statement completion, code collapse, quick fixes, and more.
  • Integrated compiler - Increase developer productivity by accelerating the build-debug cycle and providing immediate error reporting using the integrated incremental compiler.
  • Interactive debugging - Quickly track down and resolve problems using the integrated debugger to set breakpoints, inspect variables and expressions, change values, and monitor trace messages.
  • Rich visual layout - Assemble and preview Flex application interfaces in design view using a rich library of built-in or custom components.
  • Rich data visualization - Create data dashboards and interactive data analysis by simply dragging and dropping a chart type and linking it to a data source using the Flex Charting library, available as an add-on to Flex Builder 2 or as a stand-alone product.

Tip: The Flex Builder Start Page contains links to many useful resources. To display this page, select Help > Flex Start Page from the menu bar.

Changes in the 2.0.1 update

  • Macintosh support - The Flex Builder 2.0.1 update adds support for Macintosh OS X.
  • Reorganized preferences - Flex Builder preferences have been reorganized.  If you have changed the following preferences, they will be lost upon upgrade:

    • Highlight matching braces
    • Keep close braces correctly indented
    • Code Assist auto-activation settings

    This is because the separate preferences for each type of editor (MXML, ActionScript, etc.) have been eliminated and replaced with a single set of shared preferences for all editors.  You can adjust these new settings under Flex > Editors in the preferences window.

  • Support for Runtime CSS - Flex Builder now supports Runtime CSS by allowing users to specify CSS files that need to be compiled into SWFs in Flex projects. There is a new context menu item when you select a CSS file in the Navigator panel named "Compile CSS to SWF" that becomes checked once it is selected. After the CSS file is compiled into a swf, the generated swf gets copied to the output directory. If build automatically is turned on, any changes made to the css file will trigger a recompile of the swf.
  • Context root for server-based projects - The New Project Wizard now allows you to specify a context root when creating a Flex Data Services (FDS) or ColdFusion project. The context root is a name assigned when deploying a J2EE web application (FDS and ColdFusion are considered “web applications” from the J2EE perspective). It distinguishes one web application from another web application on the server and forms part of its root URL. The Flex services configuration needs to know this value in order to construct the correct URLs to the FDS or ColdFusion root. If it is incorrect, Flex services may throw errors at runtime relating to unreachable server URLs.

    Note: ColdFusion servers that use the standard configuration (that is, they don't use the multiserver or J2EE configurations) can leave this setting at its default value. However, if you created projects with the 2.0.0 version of the ColdFusion Extensions for Flex Builder, you must add -context-root "" to the additional compiler arguments in order to compile with Flex Builder 2.0.1. For more information, see the Flex Team Blog.
  • Modules - The Flex Builder 2.0.1 update supports the new Flex Module feature. You use the <mx:Module> tag as the root tag of a custom component, which is dynamically loaded at runtime. Module appears as an option in the wizard dialog for creating a new MXML component. ModuleLoader is an item in the design mode Components panel. A ModuleLoader has a “url” property, which specifies the module to load. For more information, see the "Creating Modular Applications" discussion in Flex 2 Developer's Guide.

Compatibility issues

Flex Builder 2 projects are not compatible with Flex Builder 1.5 projects.

Known issues


  • (Macintosh-only) Release a debug session - When an application throws a runtime exception (RTE) and you terminate a debug session, Flex Builder does not release the debug session when the browser window is closed. To fix the problem, completely close your browser with Command-Q.
  • Modules - Module tag source's breakpoint is not hit if the MXML file is not included in a runnable application file.
  • Debugging with Firefox - Firefox is closed incorrectly and displays an error message upon error message on restart when closing a debug session.   

Project definition

  • Opening old Flex projects - The Flex Builder 2.0.1 update cannot open projects that were created with pre-release versions of Flex Builder 2. Flex Builder 2 beta-level projects must be recreated in Flex Builder 2.0.1.
  • Double-byte project name - Design view stops working after renaming the project name with double-byte characters.  


  • Problems panel with FDS - If Flex Data Services does not contain up-to-date Flex framework SWC files, the Problems panel sometimes displays errors for IFlexModuleFactory. Updating FDS to the latest version should resolve the problem.
  • (Macintosh-only) Spaces in project folder name - Running a file on a remote FDS server doesn't work if the project folder has a space.
  • Sample applications on Vista - On Windows Vista, when adding one of the sample applications as a Flex Builder project, Vista reverts from the Aero color scheme to the Windows Vista Basic color scheme.
  • Incorrect location for link report - When you use -link-report <output-file> as an "Additional compiler argument" in the Compiler section of the Properties dialog of a Flex, ActionScript, or Flex Library project, you should specify <output-file> as an absolute path such as c:\myfolder\report.xml or /Users/Me/Documents/report.xml. If you use a relative path such as "myfolder/report.xml", the report is erroneously written to your Flex Builder or Eclipse root folder, rather than to the project's root folder.
  • BEA Workshop - Launching Workshop's Eclipse from 'Adobe Flex Builder 2 Eclipse Launcher' generates error on Workshop's Welcome Page.  
  • RSA 7 Plug-in - Viewing EJB Deployment preferences causes error on viewing project properties with RSA 7 Plugin.
  • Embedding large double-byte fonts - Embedding large double-byte font consumes all memory. The workaround is to allocate more memory to Eclipse.
  • Running SWF files from Navigator on Macintosh - Clicking on SWF files in Navigator doesn't launch them on the Macintosh.
  • (Macintosh-only) Stand-alone Flash Player - The stand-alone Flash Player that ships in the flex_builder_root/Player/debug folder is English-only. A fully localized version is available from the Adobe Flash Player Support Center. This is especially important for developers who wish to publish projectors on the Macintosh      

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