function showGoogleTranslate(){
	document.getElementById('google_translate_element').style.visibility = 'visible';
}

function hideGoogleTranslate(){
	document.getElementById('google_translate_element').style.visibility = 'hidden';
}

function otevri_okno(co_v_nem, sirka, vyska){
	s_sirka=screen.width;
	s_vyska=screen.height;
	sirka+=20;
	vyska+=20;
	if((vyska<s_vyska-40)&&(vyska<s_vyska-30)){
	    window.open(co_v_nem, '', 'toolbar=no,resizable=yes,scrollbars=no,directories=no,width=' + String(sirka) + ',height=' + String(vyska));
	} else {
		window.open(co_v_nem, '', 'toolbar=no,resizable=yes,scrollbars=yes,directories=no,width='+String(s_sirka-40)+',height='+String(s_vyska-80));
	}
}

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

function XmlHttpPost(xml_http, callback, url, params){
	params = params + "&rand=" + rand(1,9999999);
	xml_http.onreadystatechange = callback;
	xml_http.open("POST", url, true);
	xml_http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	xml_http.setRequestHeader("Content-length", params.length);
	xml_http.setRequestHeader("Connection", "close");
	xml_http.send(params);
	return 1;
}

function rand(min, max){
	// http://kevin.vanzonneveld.net
	// +   original by: Leslie Hoare
	// +   bugfixed by: Onno Marsman
	// %          note 1: See the commented out code below for a version which will work with our experimental (though probably unnecessary) srand() function)
	// *     example 1: rand(1, 1);
	// *     returns 1: 1
	
	var argc = arguments.length;
	if (argc === 0) {
		min = 0;
		max = 2147483647;
	}
	else 
		if (argc === 1) {
			throw new Error('Warning: rand() expects exactly 2 parameters, 1 given');
		}
	return Math.floor(Math.random() * (max - min + 1)) + min;
}