var httpRequest = false;
var url = "bilder.xml";
function sendRequest(pom) {
	httpRequest = false;
	if (window.XMLHttpRequest) { // Mozilla, Safari,...
		httpRequest = new XMLHttpRequest();
	} else if (window.ActiveXObject) { // IE
		try {
			httpRequest = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try {
				httpRequest = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e) {}
		}
	}
	if (httpRequest.overrideMimeType) {
		httpRequest.overrideMimeType('text/xml');
		// zu dieser Zeile siehe weiter unten
	}
	document.getElementById('pom').value = pom;
	if (!httpRequest) {
		alert('XML nicht verfügbar');
		return false;
	}
	httpRequest.onreadystatechange = responseInhalt;
	httpRequest.open('GET', url, true);
	httpRequest.send(null);
}

function responseInhalt() {
	if (httpRequest.readyState == 4) {
		if (httpRequest.status == 200) {
			var xmldoc = httpRequest.responseXML;
			if(document.getElementById('pom').value=="minus"){
				var key = (parseInt(document.getElementById('load').value)-1);
			}else{
				var key = (parseInt(document.getElementById('load').value)+1);
			}
			var root_node = xmldoc.getElementsByTagName('galerie').item(0);
			var menge = root_node.getElementsByTagName('letztes').item(0).firstChild.data;
			if((key)>menge) key=1;
			if((key)<1) key=menge;
			document.getElementById('load').value = key;
			var loadkey = parseInt(key-1);
			var bild = root_node.getElementsByTagName('schluessel').item(loadkey).firstChild.data;
			var bus = root_node.getElementsByTagName('unterzeile').item(loadkey).firstChild.data;
			document.getElementById('picture').innerHTML = '<div class="pic"><img src="_img/_familie/'+bild+'.jpg" alt="'+bus+'" /></div><div class="picnav"><a href="javascript:sendRequest(\'minus\');void(0);" class="left">&#60; zurück</a><a href="javascript:sendRequest(\'plus\');void(0);" class="right">weiter &#62;</a></div>';
		}
	}
}

function wechselBild(seite,zeige,classe){
	nextval=zeige;
	if(zeige==1){
		document.getElementById('picselect1').className=classe+'on';
		document.getElementById('picselect2').className=classe;
	}else{
		document.getElementById('picselect2').className=classe+'on';
		document.getElementById('picselect1').className=classe;
	}
	document.getElementById('secontainer').style.backgroundImage="url(_img/"+seite+"/"+nextval+".jpg)";
}