index.html

<!DOCTYPE html>
<html>
<head>
	<meta charset="UTF-8">
	<title>&lt;a-qrcode&gt;</title>

	<!-- Importing Web Component's Polyfill -->
	<script src="//cdnjs.cloudflare.com/ajax/libs/polymer/0.0.20131107/polymer.min.js"></script>
	<script src="src/qrcode.min.js" type="text/javascript"></script>

	<!-- Importing Custom Elements -->
	<link rel="import" href="src/a-qrcode.html">
</head>
<body>

	<!-- Using Custom Elements -->
	<form onsubmit="return generateQRCode();">
		<input id="url" name="url" value="http://www.google.com"/>
		<input type="submit" value="generate"/>
	</form>
	<a-qrcode id="qrcode" width="360" height="360" code="http://www.google.com"></a-qrcode>
	<script>
	function generateQRCode() {
		document.getElementById('qrcode').code = document.getElementById('url').value;
		return false;
	}
	</script>

</body>
</html>