Modifying a spark.components.DropDownList to act like mx.controls.PopUpButton

Question

Is it possible to add a "push button" functionality to Spark's DropDownList? (I.e. you select an item from the list and then click at the "main button" to dispatch an event).

Can this be achieved by creating a custom skin based on the DropDownListSkin and replacing the label there by a button:

<s:Label id="labelDisplay" verticalAlign="middle" maxDisplayedLines="1" 
    mouseEnabled="false" mouseChildren="false"
    left="7" right="30" top="2" bottom="2" width="75" verticalCenter="1" /> 

Any feedback is welcome, I'm not experienced in customizing skins yet.

Or maybe I should

override mx_internal function openButton_buttonDownHandler()

?