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As we proceed through the Drawing API, all the examples in this chapter will use the same basic file setup, shown below. Use this code as the basis for all of the examples we create. You will only have to change the contents of the drawScreen() function:
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Ch2BaseFile - Template For Chapter 2 Examples</title>
<script src="modernizr-1.6.min.js"></script>
<script type="text/javascript">
window.addEventListener('load', eventWindowLoaded, false);
function eventWindowLoaded() {
canvasApp();
}
function canvasSupport () {
return Modernizr.canvas;
}
function canvasApp(){
if (!canvasSupport()) {
return;
}else{
var theCanvas = document.getElementById("canvas");
var context = theCanvas.getContext("2d");
}
drawScreen();
function drawScreen() {
//make changes here.
context.fillStyle = '#aaaaaa';
context.fillRect(0, 0, 200, 200);
context.fillStyle = '#000000';
context.font = '20px _sans';
context.textBaseline = 'top';
context.fillText ("Canvas!", 0, 0);
}
}
</script>
</head>
<body>
<div style="position: absolute; top: 50px; left: 50px;">
<canvas id="canvas" width="500" height="500">
Your browser does not support HTML5 Canvas.
</canvas>
</div>
</body>
</html>