Tweening

Tweening covers transitioning from a property's value to another value. The AIR technology does not include native forms of tweening; therefore, if it is desired to use tweening, it is necessary to use a specific library.

As of currently, the most stable ActionScript 3 library for tweening is com.eclecticdesignstudio.motion. Consider grabbing the .swc library of one of the releases in the library's repository.