var previousOpenedLIId;

function hide(id)
{
	if (document.getElementById('subcategory'+id).style.display == 'none')
	{
		if (previousOpenedLIId != null)
		{
			document.getElementById('subcategory'+previousOpenedLIId).style.display = 'none';
		}
		document.getElementById('subcategory'+id).style.display = 'block';
	}
	else
	{
		document.getElementById('subcategory'+id).style.display = 'none';
	}
	
	previousOpenedLIId = id;
}

function getXhr()
{
	var xhr = null; 
	if(window.XMLHttpRequest)
	xhr = new XMLHttpRequest(); 
	else if(window.ActiveXObject)
	{
		try
		{
			xhr = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e)
		{
			xhr = new ActiveXObject("Microsoft.XMLHTTP");
		}
	}
	else
	{
		alert("Votre navigateur ne supporte pas les objets XMLHTTPRequest..."); 
		xhr = false; 
	} 
	return xhr;
}

function boxDisplay(boxId)
{
	if (document.getElementById('filter').style.display == 'block')
	{
		document.getElementById(boxId).style.display = 'none';
		document.getElementById('filter').style.display = 'none';
	}
	else
	{
		document.getElementById('filter').setAttribute("onclick", "boxDisplay('"+boxId+"')");
		document.getElementById('filter').style.display = 'block';
		document.getElementById(boxId).style.display = 'block';
	}
}

function postMessage()
{
	document.getElementById('read_messages').style.display = 'none';
	document.getElementById('post_messages').style.display = 'block';
}

function readMessage()
{
	document.getElementById('read_messages').style.display = 'block';
	document.getElementById('post_messages').style.display = 'none';
}

function centerBox(width, height, picture)
{
	var posX = ((width / 2) + 20);
	var posY = ((height / 2) + 30);
	var boxPicture = document.getElementById('box_picture');
	
	boxPicture.style.width = width+"px";
	boxPicture.style.height = height+"px";
	boxPicture.style.marginLeft = "-"+posX+"px";
	boxPicture.style.marginTop = "-"+posY+"px";
	
	boxPicture.innerHTML = '<span style="cursor: pointer; font-size:18px; color:#5694b6;" onclick="boxDisplay(\'box_picture\')"><img style=" border: solid; border-width: 3px; border-color:#89c5eb; " src="pictures/'+picture+'" /><br /><strong>Cliquez pour fermer l\'image.</strong></span>';
}