function getAbsX(elt) 
{ 
  if (!elt) return;

  return (elt.x) ? elt.x : getAbsPos(elt,"Left"); 
}

function getAbsY(elt) 
{ 
  if (!elt) return;

  return (elt.y) ? elt.y : getAbsPos(elt,"Top"); 
}

function getAbsPos(elt,which) 
{
  iPos = 0;
  while (elt != null) {
    iPos += elt["offset" + which];
    elt = elt.offsetParent;
  }
  return iPos;
}

function toggleVisible(elt, parent)
{
  if (!elt) return;

  if (elt.style.visibility == 'visible' || elt.style.visibility == 'show')
    elt.style.visibility = 'hidden';
  else 
  {
    setPosition(elt, parent);
    elt.style.visibility = 'visible';
  }
}

function setPosition(elt, parent)
{
  if (!elt) return;

  elt.style.left = getAbsX(parent);
  elt.style.top  = getAbsY(parent) + 27;
}

function hideMenu(id)
{
  var elt = document.getElementById('Layer' + id);
  if (elt)
    elt.style.visibility = 'hidden';
}