[FlashMove]

Skinning the Callout and CalloutButton for Flash Builder (Flex) introduces a few challenges.
The default Callout skin is a little more complex than the typical mobile skin. A few issues to highlight:

1. The arrow skin part is implemented as a subclass named CalloutArrow
2. The backgroundColor gradient fill also fills the arrow for all callout and arrow position combinations
3. The arrow is not given a position in the skin. Instead, Callout manages the arrow position based on the Callout's position relative to the owner.
4. The skin implements open/close state transition effects in ActionScript

To make Callout skinning easier, spark.skins.mobile.CalloutSkin exposes protected properties that subclasses can modify in order to tweak the existing visuals. For example, the screenshot and code below show how to square up the Callout's corners, removed the background gradient, and specified new default sizes for the arrow.
http://blogs.adobe.com/jasonsj/2011/...outbutton.html