// showhide by pip
// prerequisite: scriptaculous

var http_request = false;
function InitAjax()
{
	http_request = false;
	if (window.XMLHttpRequest) {
		http_request = new XMLHttpRequest();
	} 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('cannot create an xmlhttp instance!');
		return false;
	}
}

function ShowHide(id)
{
	InitAjax();
	if(http_request) {
		if(document.getElementById("tr_firstpost_"+id).style.display == 'none') {
			http_request.onreadystatechange = function() {
				if(http_request.readyState == 4) {
					if(http_request.status == 200) {
						td_firstpost = document.getElementById("td_firstpost_"+id);
						td_firstpost.innerHTML = http_request.responseText;
					}
				}
			};
			http_request.open('POST', 'firstpost.php', true);
			http_request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
			http_request.send('id='+id);
			document.getElementById("button_firstpost_"+id).style["cursor"] = "n-resize";
			document.getElementById("tr_firstpost_"+id).style["display"] = "";
		} else {
			document.getElementById("button_firstpost_"+id).style["cursor"] = "s-resize";
			document.getElementById("tr_firstpost_"+id).style["display"] = "none";
		}
	}
}