function navigation(id)
{
	random_image();

	for(var i = 1 ; i < 6 ; i++ )
	{
		var test = "main"+i;
		var test2 = "sub"+i;

		if(id == i)
		{
			document.getElementById(test).style.display = "none";
			document.getElementById(test2).style.display = "";

		}
		else
		{
			document.getElementById(test).style.display = "";
			document.getElementById(test2).style.display = "none";
		}
	}
}

function news()
{
	document.getElementById("news_link").innerHTML = "NEWS  &nbsp;&brvbar;"; 
	document.getElementById("login_link").innerHTML = "<b>LOGIN</b>"; 
	document.getElementById("news").style.display = "none"; 
	document.getElementById("login").style.display = "";
}

function content(seite)
{
	http_request = false;
	if (window.XMLHttpRequest)
	{
		http_request = new XMLHttpRequest();
		if (http_request.overrideMimeType)
		{
			http_request.overrideMimeType('text/xml');
		}
	}
	else if (window.ActiveXObject)
	{
		try
		{
			http_request = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e)
		{
			try
			{
				http_request = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e)
			{}
		}
	}

	if (!http_request)
	{
		alert('Giving up :( Cannot create an XMLHTTP instance');
		return false;
	}
	http_request.onreadystatechange = alertContents;
	http_request.open('GET', seite, true);
	http_request.send(null);
}

function alertContents()
{
	if (http_request.readyState == 4)
	{
		if (http_request.status == 200)
		{
			var response = http_request.responseText;
			document.getElementById('content').innerHTML = response;
		}
		else
		{
			alert('There was a problem with the request.');
		}
	}
	else
	{
		document.getElementById('content').innerHTML = "<div style=\"text-align:center;\"><br /><br /><br /><br />Inhalt wird geladen<br /><br /><img src=\"grafiken/load_animation.gif\"></div>";
	}
}