function changeClass(obj, newClass)
{
    if ( typeof(obj) == "string"){
        obj = new getObj(obj);
        obj = obj.obj;
    }
    obj.className = newClass;
}

function getObj(id)
{
  if (document.getElementById)
  {
    this.obj = document.getElementById(id);
    this.style = document.getElementById(id).style;
  }
  else if (document.all)
  {
    this.obj = document.all[id];
    this.style = document.all[id].style;
  }
  else if (document.layers)
  {
    this.obj = document.layers[id];
    this.style = document.layers[id];
  }
}

function openTab(layer_id,aLayers){
    closeAllLayers(aLayers);
    changeClass("a"+layer_id,"selected");

    layer = new getObj(layer_id);

    if (  layer.style.display == "block" )
    {
        layer.style.display = "none";
    }
    else
    {
        layer.style.display = "block";
    }
}

function closeAllLayers(aLayers)
{
    for(i=0;i<aLayers.length;i++)
    {
        setDisplayTo(aLayers[i],"none" );
        changeClass("a"+aLayers[i],"");
    }
}

function setDisplayTo( id , value )
{
    layer = new getObj(id);
    layer.style.display = value;
}


function show(id)
{
    layer = new getObj(id);
    layer.style.visibility = "visible";
}

function hide(id)
{
    layer = new getObj(id);
    layer.style.visibility = "hidden";
}

function swap(id)
{
    layer = new getObj(id);

    if ( layer.style.display == "none" )
        layer.style.display = "block";
    else
        layer.style.display = "none";
}