var xmlhttp;
function ChangeMark(mark_id, action, id_model_select, mode, id_loading, default_name)
{
 default_name = default_name || '---';
 if (mark_id != 0)
 {
   document.getElementById(id_model_select).disabled = true;
   document.getElementById(id_model_select).selectedIndex = 0;
   if (document.getElementById(id_loading))
       document.getElementById(id_loading).style.display = 'inline-block';
   xmlhttp = createRequest();
   xmlhttp.onreadystatechange = function()
   {
     if (xmlhttp.readyState == 4)// "complete"
     {
       if (xmlhttp.status == 200) // "OK"
       {
         var models_str;
         models_str = xmlhttp.responseText.substr(0, xmlhttp.responseText.length-1);

         var i;
         var model_select = document.getElementById(id_model_select);
         models_str = '0,'+default_name+';' + models_str;

         if(models_str)
         {
           var model_list = models_str.split(';');
           model_select.options.length = model_list.length;
           for (i = 0; i < model_list.length; i++) {
             model_select.options[i].text = (model_list[i]).split(',')[1];
             model_select.options[i].value = (model_list[i]).split(',')[0];
           }
         }
//         model_select.selectedIndex = 0;
         model_select.disabled = false;
       }
       if (document.getElementById(id_loading))
         document.getElementById(id_loading).style.display = 'none';
     }
   };
   xmlhttp.open("GET", 'http://'+location.host+'/auto/_load_models.php?mode='+mode+'&action='+action+'&mark_id='+mark_id, true);
   xmlhttp.send(null);
 }
 else
 {
   document.getElementById(id_model_select).disabled = 1;
   document.getElementById(id_model_select).options.length = 1;
   document.getElementById(id_model_select).options[0].text = default_name;
   document.getElementById(id_model_select).options[0].value = 0;
   document.getElementById(id_model_select).selectedIndex = 0;
 }
}