Release notes | Flex 4.5 SDK

Adobe® Flex® 4.5 SDK Release Notes

Welcome to the Adobe Flex 4.5 SDK preview release.

About Flex

Flex SDK includes the Flex framework (also known as the Flex class library), Flex command-line compilers, the Flex debugger, the ASDoc utility, and the debugger version of Adobe® Flash® Player and Adobe® AIR® runtimes. Use the Flex SDK to develop, compile, and deploy Flex applications that connect to XML and SOAP web services or connect to various server technologies such as PHP, Adobe® ColdFusion®, Java, and .NET using a server technology such as BlazeDS. Flex applications can be built and configured to target browsers via the Flash Player runtime and desktops or mobile devices via the AIR runtime.

What's New

This Flex 4.5 SDK build is and contains:

  • Flash Player
  • TLF
  • OSMF

We strongly suggest you DO NOT overlay different AIR, AIR SDK or Flash Player versions into Flex 4.5 SDK build Development, debugging and deployment workflows are only certified with the AIR and Flash Player versions installed with the Flex SDK.

Install Your Software

Installation instructions

The Flex SDK installation is delivered as a ZIP file and contains the Flex framework, Adobe AIR framework, and command-line tools, such as the mxmlc command-line utility, Adobe AIR command-line utility, the ASDoc utility, the Flex command-line debugger, and the debugger version of Flash Player.

Uninstall current Flash Player

You should use Flex SDK with the latest version of the debug Flash Player 10. Prior to installing the Flex SDK, you should uninstall your current Flash Player.

Windows–Plugin-based browsers

Run the appropriate uninstaller available from this Tech Note.


Run the appropriate uninstaller available from this Tech Note.


Manual removal (for users who installed the plug-in via Install script):

  • Delete the binary and the flashplayer.xpt file in directory /home/<user>/.mozilla/plugins/

RPM removal:

  1. As root, enter the following command: 

    # rpm -e flash-plugin
  2. Click Enter and follow the prompts.

Install the Flex SDK

  1. Download Flex SDK ZIP file from the Adobe website or the Adobe Open Source site.

  2. Create a directory to contain Flex SDK.

  3. Extract the Flex SDK ZIP file to this directory. The Flex SDK contains the following directories:

    • /ant — Contains Flex Ant Tasks.
    • /asdoc — Contains helper files for the ASDoc tool that creates HTML documentation from your MXML and ActionScript source code.
    • /bin — Contains the mxmlc, compc, asdoc, and fdb utilities. The bin directory also contains the jvm.config file, which specifies Java settings that you can modify, if necessary.
    • /frameworks — Contains compiled framework classes, configuration files, and framework source code.
    • /lib — Contains JAR files used by the utilities.
    • /runtimes — Contains installers for the Adobe AIR runtime inside the air directory and installers for debug versions of Flash Player 9 inside the player directory.
    • /samples — Contains sample applications.
    • /templates — Contains HTML templates for Flash Player detection and browser integration and inside the air folder, a sample Adobe AIR application.xml file.
  4. Ensure that the Java Runtime Environment (JRE) is installed on the computer and that the java_home/bin directory is defined in the system path. JRE 1.5,or 1.6 is required.

  5. Install the appropriate debug Flash Player from the install_root/runtimes/player/platform directory.

  6. (Optional) When the Flash Player installation finishes, restart your computer to ensure that the updated Flash Player browser plug-in is enabled.

Compatibility Issues

There have been some changes made in Flex 4.5 SDK that alter certain behaviors compared to Flex 4. To get the full list of issues, please refer to the Flex Backwards Compatibility document. In most cases, you can maintain Flex 4 (or even Flex 3) behavior by using the compiler argument, -compatibility-version.

Using the Data Visualization Components with Flex SDK

As of Flex 4, the data visualization components are part of the full SDK distribution.

Using Automated Testing with Flex SDK

As of Flex 4, automated testing support is part of the full SDK distribution.

Known Issues and Notable Changes

This section contains selected known issues and notable changes since the previous release. For a complete list of Flex issues and their status, see the public bugbase. The public bugbase lets you search for known issues, comment on them and add new bugs.

Tip: Use Filters to customize your search.

Mobile Features

  • SDK-29331: Multiple TabbedViewNavigator tabs can look selected at the same time

  • SDK-29159: Scroll position is not adjusted when the app goes to landscape, so the focused component is not on the screen

  • SDK-30068: Infinite loop occurs when a BitmapImage uses image smoothing and its width and height is 0

  • SDK-28980: A horizontal mobile list does not have bounce/pull effects on its right and left boundaries when the content is smaller than the size

  • SDK-30070: The first view created in a ViewNavigator isn't measured by the time it dispatches a CREATION_COMPLETE event

  • SDK-28882: Transitions in a Skin that affect the size of the skin should not target the skin itself (target="{this}")

  • SDK-27538: The mobile application background is transparent, but at startup time is pushed down to set the stage color. There is no way to set the stage color at runtime, so the only way to do this is to create an opaque rectangle in the background of your view.

  • SDK-29145: Using editable text in an item renderer can lead to inconsistent and unpredictable behavior with selection, focus, and on-screen keyboard interaction. Text editing should be done in the ActionBar, a separate View, or in a pop-up control.

  • SDK-30013: When using a tabbed application on iOS and switching to landscape mode, the tabBar and actionBar both take up most of the available space above the soft keyboard, leaving barely enough room to show one line of text. It may be necessary to add event list to the application for the softKeyboard events and hide/show the tab bar as in this example: 

    protected function tabbedviewnavigatorapplication1_softKeyboardActivateHandler(event:SoftKeyboardEvent):void 
 if (event.isDefaultPrevented()) return; tabbedNavigator.hideTabBar(false); 
} protected function tabbedviewnavigatorapplication1_softKeyboardDeactivateHandler(event:SoftKeyboardEvent):void 
{ if (event.isDefaultPrevented()) return; tabbedNavigator.showTabBar(false); 

  • SDK-30128: The SlideViewTransition class doesn't properly restore the initial view's includeInLayout property to true when the destructionPolicy is set to "never". This will prevent the view from participating in layout when it is redisplayed by the application. To workaround this issue, developers can manually restore the includeInLayout property of all views to true when they receives the "add" event.

  • If you're using projects created in an earlier version of FB (eg the Max Preview Release), it may be necessary to edit your application descriptor file (application.xml) and remove the line:

Desktop Features

  • SDK-24055: When Alert is used in a module but not defined in the main app, current moduleFactory should be passed to so Alert can pick up styles correctly

  • SDK-28374: Spark: ModuleLoader will not load mx:Module if s:ModuleLoader is in mx:Application

  • SDK-29825: Due to problems in some browsers that could cause security issues, Flash Player no longer makes requests for URLs that contain characters that aren't considered "low ASCII" on Mac. You should use encodeURI or encodeURIComponent before making the request.

  • SDK-23154: Avoid setting backgroundColor on a global style selector. This style gets picked up by several components that may cause unintended behavior to avoid this, set the backgroundColor style on specific components instead of on the global style selector.

  • SDK-29185: When a screen reader is used, Spark TextInput fields used as item editors in Spark DataGrid leave unwanted unknown variant children in MSAA

  • SDK-29819: Spark List can respond slowly when blocks of dataProvider items are replaced, inserted, or removed and the dataProvider is large. See SDK-29819 for more information, including a possible workaround

  • SDK-29884: Spark DateTimeFormatter and CurrencyFormatter may exhibit poor performance on Mac, which could hurt scrolling performance of large DataGrids that use them. If you encounter performance problems, consider using the MX versions of these formatters for now, or, in the case of CurrencyFormatter, you may find the Spark version to be fast enough when using an ISO code rather than a currency symbol. See the comments in bug SDK-29884 for more details.

  • SDK-29100: UncaughtError handling does not work for exceptions thrown from Flex modules

  • FLEXDMV-2562: To workaround the issue, refer to the following KB article

  • FLEXENT-1435: To workaround the issue, patch gridMouseUpHandler() in SparkDataGridAutomationImp as per the comments in the bug listing


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