function showSug()
{
	document.getElementById('cat').style.display = 'none';
	document.getElementById('cat1').style.display = 'block';
	document.getElementById('subcat').style.display = 'none';
	document.getElementById('subcat1').style.display = 'block';
	document.getElementById('suggest').style.display = 'none';
	document.getElementById('back').style.display = 'block';
}

function showCat()
{
	document.getElementById('cat').style.display = 'block';
	document.getElementById('subcat').style.display = 'block';
	document.getElementById('suggest').style.display = 'block';
	document.getElementById('kategoria').value = '';
	document.getElementById('podkategoria').value = '';

	document.getElementById('cat1').style.display = 'none';
	document.getElementById('subcat1').style.display = 'none';
	document.getElementById('back').style.display = 'none';
}

function setQueryString(name){
  var queryString = "";
  var frm = document.forms[name];
  var numberElements = frm.elements.length;
  queryString = "id_kat=" + encodeURIComponent(frm.elements[0].value);
  return queryString;
}


function pobierz(){
	var strona     = "linki/dane.php"
	var type       = "GET";
	var asynch     = true;
	var nameForm   = "dane";		// nazwa formularza z którego pobiera dane
	var query      = setQueryString(nameForm);
	var nameResult = "wynik";		// nazwa (id) elementu w którym ma być wynik
	var div        = document.getElementById(nameResult);
	var url        = strona + "?" + query;

	if( window.XMLHttpRequest ){
		request = new XMLHttpRequest();
	} 
	else if( window.ActiveXObject ){
		request = new ActiveXObject("Microsoft.XMLHTTP");
	}
	else {
		alert("Przeglądarka nie pozwala na korzystanie AJAX'a");
	}	
	
	if( request ){
		request.onreadystatechange=response;
		request.open(type, url, asynch);
		request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=utf-8");
		request.send(null);
	}
	function response() {
			if( request.readyState == 4 ){
				if( request.status == 200 ){
					var doc = request.responseXML;
				}
				else {
				  alert("Wystąpił problem z komunikacją");
				}
			}
			for(j = 0; j < document.dane.id_podkategoria.options.length; j++){
					document.dane.id_podkategoria.options[j] = null; }

			pod = doc.getElementsByTagName("podkategoria");
			for(var i=0; i < pod.length; i++){
				document.dane.id_podkategoria.options[i] = new Option();
				document.dane.id_podkategoria.options[i].text = pod[i].childNodes[1].childNodes[0].nodeValue;
				document.dane.id_podkategoria.options[i].value = pod[i].childNodes[0].childNodes[0].nodeValue;
			}
	}

}