var cas = 300		// jak dlouho se bude cekat, nez menu zmizi
	var pocet_menu = 3;
	
	var casovac

	function getObj(id) {
   		if(Boolean(document.getElementById)) {
    		return document.getElementById(id);
   		} else if(Boolean(document.all)) {
    	  	return eval('document.all.'+id);
		}
	}

	function show(id) {
		hide_all()
		clearTimeout(casovac);
		cas = null;
		id = getObj('submenu_' + id);
		id.style.display = "";
		hide_danger_objects('hidden');
	}
	
	function mousein() {
		clearTimeout(casovac);
		cas = null;
	}
	
	function mouseout() {
		casovac = setTimeout("hide_all()", cas);
	}
	
	function hide(id) {
		id = getObj('submenu_' + id);
		id.style.display = "none";
	}
	
	function hide_all() {
		for (i=1; i<=pocet_menu; i++) {
			hide(i);
		}
		hide_danger_objects('visible');
	}
	
	function hide_danger_objects(change) {
		var combo = document.body.getElementsByTagName("SELECT");
		for (var i=0; i<combo.length; i++) {
			combo[i].style.visibility=change;
		}
	}


// zmena obrazku po najeti na odkaz
	function changePicture(obj) {
		var ret = obj.src
		var pos = ret.lastIndexOf('.');
		var ret = ret.substring(0, pos) + '_active' + ret.substring(pos, ret.length);
		obj.src = ret;
	}

	function backPicture(obj) {
		var ret = obj.src
		var pos = ret.lastIndexOf('_');
		var ret2 = ret.substring(0, pos) + ret.substring(pos+7, ret.length);
		obj.src = ret2;
	}

	function okno(ident, sirka, vyska) {
		sirka = sirka + 35;
		vyska = vyska + 35;
		var posX = (screen.availWidth - sirka)/2;
		var posY = (screen.availHeight - vyska)/2;
		var opt = "toolbar=0, location=0, directories=0, status=0, menubar=0, scrollbars=0, resizable=1, width=" + sirka + ", height=" + vyska + ", left=" + posX + ", top=" + posY;
		window.open("photo_show.php?file="+ident+"&", "_blank", opt);
	}

	function openWindow(theURL,winName,features) { //v2.0
		window.open(theURL,winName,features);
	}