var maintabname;
var previoustab = null;

// return arrays contatin tablist diveded by td
function gettablist()
{
	return document.getElementById(maintabname).getElementsByTagName("li");
}

function showcontent(selectedtab)
{
  if (previoustab != null)  
  { // hide previous contents    
    previoustab.parentNode.className="";
    document.getElementById(previoustab.getAttribute("rel")).style.display="none";
    
	// hide previous brief
	document.getElementById("brief" + previoustab.getAttribute("rel")).style.display = "none";
  }

  // remember previous for fast update
  previoustab = selectedtab; 
  
  // show current contents
  selectedtab.parentNode.className="selected";
  document.getElementById(selectedtab.getAttribute("rel")).style.display="block";
  
  tabname = "TowersCatalog" + selectedtab.getAttribute("rel"); 
  document.getElementById(tabname).select();
  document.getElementById(tabname).focus();
  
  // show current brief
  briefname = "brief" + selectedtab.getAttribute("rel"); 
  document.getElementById(briefname).style.display="block";
  
}

function initContent(tabname, selectedid)
{
  maintabname = tabname;
 
  // display default tab
  var tablist = gettablist();
  showcontent(tablist[selectedid].getElementsByTagName("a")[0]);
}