One thing that’s really useful to Flex 3/AIR coders is the ActionScript 3 CoreLib (AS3CoreLib). It contains MD5, JSON, and some other really useful ‘routines’.

Following are guidelines on getting AS3CoreLib compiled for Flex 3 Moxie.

First of all you need a properly installed recent copy of Apache Ant, meaning the ant script needs to be on your system path (environment variable).

Download the corelib-.90.zip from the downloads section on the project site and unzip the contents into a folder, which I’ll reference as <corelib-home>.

Open up the build.properties in the <corelib-home>/build folder in your favourite text editor and amend the following properties to reflect your Flex 3 setup:

• flex2sdk.bin.dir
• flex2sdk.lib.dir

For example my Flex 3 Builder is installed in “C:Program FilesAdobeFlex Builder 3″ . So my amended build.properties file contains the following two lines:

flex2sdk.bin.dir = C:/Program Files/Adobe/Flex Builder 3/sdks/moxie/bin
flex2sdk.lib.dir = C:/Program Files/Adobe/Flex Builder 3/sdks/moxie/frameworks/libs

Now open up a command prompt and navigate to the <corelib-home>/build folder. The Flex 3 Beta install on Windows provides a pre-configured command-prompt with environment variables setup to point to the bundled Flex 3 SDK. You can find the shortcut to this command prompt in the Adobe programme group.

At the command prompt type:

ant

which should kickstart the build process and if everyone runs ok, you should find a corelib.swc in <corelib-home>/bin.

Finally you can add corelib.swc as a library via the Build Path dialogue box in your Flex 3 project properties.

Hope it helps. Good luck.