function changeSizeForTop(){
		
	top_category_id = document.forms["topItemSearchForm"].elements["category"].selectedIndex;

	//reset city select
	var len = document.forms["topItemSearchForm"].elements["size"].length;
	document.forms["topItemSearchForm"].elements["size"].length = 1;
	document.forms["topItemSearchForm"].elements["size"].selectedIndex = 0;
	//create url
	action_url = "/api/get_size/json/" + top_category_id;
	//send request
	sendRequest(setSizeForTop,'','GET',action_url,true,true);
	
}
function setSizeForTop(returnObj){
	//conversion json to array
	var dat = eval("("+returnObj.responseText+")");
	var j=1;
	for(var i in dat){
		document.forms["topItemSearchForm"].elements["size"].length++;
		document.forms["topItemSearchForm"].elements["size"].options[j].text=dat[i];
		document.forms["topItemSearchForm"].elements["size"].options[j].value=i;
		j++;
	}
}