function openNav(trg,myParent){

var childList=trg.getAttribute('childs').split(",");

if(document.getElementById("tr"+childList[0])){
tmpI = 0;
}
else{
tmpI = 1;
}

if(!document.getElementById("tr"+childList[tmpI]))return false;

   if(document.getElementById("tr"+childList[tmpI]).style.display=="table-row"){
xxx="none";
}
else{
xxx="table-row";
}
for(var i=0;i<childList.length;i++){

  if(document.getElementById("tr"+childList[i])){
   if(xxx=="none"){document.getElementById("tr"+childList[i]).style.display=xxx}else {if(document.getElementById("tr"+childList[i]).getAttribute("ITEM_PARENT")==myParent)document.getElementById("tr"+childList[i]).style.display="table-row"}
 }
}
}