function closeList(listID)
  {
    lista = document.getElementById(listID);
    lista.style.display = "none";
  }
  
  function openList(listID)
  {
    closeList("listA");
    closeList("listD");
    closeList("listO");
    closeList("listL");
    closeList("listI");
    closeList("listC");
    
    lista = document.getElementById(listID);
    lista.style.display = "block";
  }
  
  
  function trim(str)
  {
    s = new String(str);
    return s.replace(/^\s*|\s*$/g,"");
  }
  
  function check(val)
  {
    if(trim(val) == "")
    {
      return false;
    }
    return true;
  }
  
  function check_form(frm,nfields)
  {
    f = document.forms[frm];
   
    for (i=0;i<nfields;i++)
    {
        if (f.elements[i].id.indexOf("*") == 0)
        {
            switch (f.elements[i].type)
            {
                case "password":
                case "text":
                case "textarea":
                {
                    if(!check(f.elements[i].value))
                    {
                      f.elements[i].style.borderColor = "#FF0000";
                      f.elements[i].style.borderStyle = "solid";
                      return false;
                    }
                    else
                    {
                        f.elements[i].style.borderColor = "";
                        f.elements[i].style.borderStyle = "";
                    }
                    
                    if(f.elements[i].name == "mail" && (f.elements[i].value.indexOf("@") == -1 || f.elements[i].value.indexOf(".") == -1))
                    {
	                    f.elements[i].style.borderColor = "#FF0000";
                        f.elements[i].style.borderStyle = "solid";
	                    alert("E-mail address not valid!");
	                    return false;
                    }
                }
                break;
               
                case "checkbox":
                {
                    if(!f.elements[i].checked)
                    {
                      f.elements[i].style.color="#FF0000";
                      f.elements[i].style.borderColor = "#FF0000";
                      f.elements[i].style.borderStyle = "solid";
                      f.elements[i].style.borderWidth = "3px";
                      return false;
                    }
                    else
                    {
                        f.elements[i].style.backgroundColor="";
                        f.elements[i].style.borderColor = "";
                        f.elements[i].style.borderStyle = "";
                        f.elements[i].style.borderWidth = "";
                    }
                }
                break;
            }
        }
    }
    f.submit();
  }
  
  
  function showDistr(zona)
  {
    //nasconde tutte le zone
    for(var i=1; i<21; i++)
    {
      var Z = 'Z';
      if(i < 10)Z += '0';
      Z += String(i);
      
      distr = document.getElementById(Z);
      distr.style.display = "none";
    }
   
   //visualizza solo la zona selezionata
   distr = document.getElementById(zona);
   distr.style.display = "block";  
  }
  
  function openoverlay(ov)
    {
        document.getElementById(ov).style.display='block';
    }
  
  function closeoverlay(ov)
    {
        document.getElementById(ov).style.display='none';
    }

 function cambiaclasse(id,nuovaClasse)
  {
	document.getElementById(id).className=nuovaClasse;
  }
  
  function cambiasrc(id,newsrc)
  {
	document.getElementById(id).src=newsrc;
  }