PopUp = function (closeString) {
	var d = document.createElement("div");
	d.id = "popup";
	d.innerHTML = "<div><a href='#'>"+closeString+"</a><br /><iframe frameborder='0' src='empty.html'></iframe></div>";
	var canvas = document.getElementById("canvas");
	canvas.insertBefore(d, canvas.firstChild);
	this.iframe = d.getElementsByTagName("iframe")[0];
	d.getElementsByTagName("a")[0].onclick = function () {document.getElementById("popup").style.display = "none";return false}
}
PopUp.prototype.setURL = function (URL) {
	this.iframe.src = URL;
}
PopUp.prototype.show = function () {
	document.getElementById("popup").style.display = "block";
}