here we go with an another cool skinning example:
1) Create your graphics in Adobe illustrator, make and fxg
2) Import it in your flash builder
3) Create the skin class
4) call the skin class from your mxml or css
here it is the complete guide:
He is working on a mobile app that requires a lot of skinning and since Flex 4 we’ve gotten a MUCH improved skinning model for Flex. Unfortunately, with Flex mobile, for performance reasons it’s a good idea to use ActionScript-only skins which means going back to the world of Flex 3 and diving into the component lifecycle a bit.