js:
document.addEventListener('DOMContentLoaded', drawCanvas, false);
function drawCanvas() {
var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
ctx.fillStyle = "#FF0000";
ctx.fillRect(0,0,150,75);
}
html:
<html>
<head>
<script src="common/js.js"></script>
</head>
<body>
<canvas id="myCanvas" width="200" height="100" style="border:1px solid #000000"></canvas>
</body>
</html>