pi.util.Element.getPosition(element)
>>> var position = pi.util.Element.getPosition( MyButton );
>>> position
{
bottom:'10px', left:'100px', right:'auto', top:'auto',
offsetLeft:110, offsetTop:500,
clientLeft:110, clientTop:500,
marginLeft:"10px", marginTop:"20px",
position:"absolute",
zIndex:"auto"
}
>>> position.offsetLeft
110
>>> position.marginTop
"20px"