function preloading(url)
{
	var xhr=createXHR();   
	xhr.onreadystatechange=function()
	{ 
		if(xhr.readyState == 4)
		{
			var content = xhr.responseText;
			var i = new Image();
                        
			i.src = content;
		} 
	}; 

	xhr.open("GET", url , true);
	xhr.send(null); 
}