function PopUpShowing(sender, eventArgs) {
    // Centers the editing form for radGrid.
    // To Use:  Setup Edit Form Heights first and then add
    //        <ClientSettings>
    //                <ClientEvents OnPopUpShowing="PopUpShowing" />
    //        </ClientSettings>
    //                
    var popUp;
    popUp = eventArgs.get_popUp();
    var gridWidth = sender.get_element().offsetWidth;
    var gridHeight = sender.get_element().offsetHeight;
    var popUpWidth = popUp.style.width.substr(0, popUp.style.width.indexOf("px"));
    var popUpHeight = popUp.style.height.substr(0, popUp.style.height.indexOf("px"));
    var NewLeft = ((gridWidth - popUpWidth) / 2 + sender.get_element().offsetLeft);
    var NewTop = ((gridHeight - popUpHeight) / 2 + sender.get_element().offsetTop);

    if (NewLeft < 0)
        NewLeft = 0;
    if (NewTop < 20)
        NewTop = 20;

    popUp.style.left = NewLeft.toString() + 'px';
    popUp.style.top = NewTop.toString() + 'px';
}