var responseXmlHttp;
responseXmlHttp=createXmlHttp();

function createXmlHttp(){  
	var httpTemp=null;
	try  {  // Firefox, Opera 8.0+, Safari
	  httpTemp=new XMLHttpRequest();
	  } catch (e)
	  {   // Internet Explorer
	  try {
	    httpTemp=new ActiveXObject("Msxml2.XMLHTTP");
	    } catch (e)
	    {httpTemp=new ActiveXObject("Microsoft.XMLHTTP");}
	  }
	return httpTemp;
}

// si el handlerForResponse es null, se asocia por defecto el nombre de la funcion
// handleResponse
function sndReq(page,handlerForResponse) {
     responseXmlHttp=createXmlHttp();
     if (handlerForResponse != null)
     	responseXmlHttp.onreadystatechange=handlerForResponse;
     else 
	     responseXmlHttp.onreadystatechange = handleResponse;     
     responseXmlHttp.open('get', page,true);     
     responseXmlHttp.send(null);
}


function sndReqWithObjectName(page,handlerForResponse) {
	enableWaitingIndicator(true);
    var responseXmlHttpParam=createXmlHttp();
    if (handlerForResponse != null) {
    	responseXmlHttpParam.onreadystatechange=handlerForResponse;
   	}
    else 
	     responseXmlHttpParam.onreadystatechange = handleResponse;  
	var caracter = '&';
    if (page.search('[?]') == -1)   
    	caracter='?';
	 responseXmlHttpParam.open('get', page+caracter+'varRandom='+ Math.random(),true);    
	 responseXmlHttpParam.send(null);
     return responseXmlHttpParam;     
}


function enableWaitingIndicator(enable) {
	try {
		document.getElementById('imgLoading').style.display =
		(enable == true) ? "block" : "none";
	}catch(e){}
}