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This works:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<script src="/js/msgv/widgets/excanvas2.js" type="text/javascript"></script>
<script type="text/javascript" charset="utf-8">
function canvasTest(){
console.log("beginning canvasTest");
var b_canvas = document.getElementById("regularCanvas");
var b_context = b_canvas.getContext("2d");
b_context.fillRect(50, 25, 150, 100);
}
</script>
</head>
<body onLoad="canvasTest()">
<canvas id="regularCanvas" style="border: 1px dotted; float: left;" class="clear" height="225" width="300"></canvas>
</body>
</html>
This doesn't:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
The only difference between the two is where I'm loading it in the page. Everything works fine when I load excanvas in the head. I get an error when I load it at the bottom of the body.
<script type="text/javascript" charset="utf-8">
function canvasTest(){
console.log("beginning canvasTest");
var b_canvas = document.getElementById("regularCanvas");
var b_context = b_canvas.getContext("2d");
b_context.fillRect(50, 25, 150, 100);
}
</script>
</head>
<body onLoad="canvasTest()">
<canvas id="regularCanvas" style="border: 1px dotted; float: left;" class="clear" height="225" width="300"></canvas>
<script src="/js/msgv/widgets/excanvas2.js" type="text/javascript"></script>
</body>
</html>
RTFM:
If you're looking to load excanvas asynchronously/conditionally, it is possible: https://stackoverflow.com/a/18520897/541023