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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /html/canvas/element/manual/drawing-paths-to-the-canvas/drawFocusIfNeeded_004.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<html>
<head>
<title>drawFocusIfNeeded()</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel="author" title="W3C">
</head>
<body>
<h1>Description</h1>
<p>This test uses drawFocusIfNeeded to draw a complex path focus then compare ImageData from before and after.</p>
<div>
<p>Before:</p>
<canvas height=100 width=100 id='original'>
</canvas>
<p>After:</p>
<canvas height=100 width=100 id=canvas>
</canvas>
</div>
<script>
test(function() {
var canvas = document.getElementById('canvas');
var context = canvas.getContext('2d');
var element = document.getElementById('element');
element.focus();
context.fillStyle = 'white';
context.fillRect(0, 0, 100, 100);
context.beginPath();
context.strokeStyle = 'black';
context.moveTo(10, 40);
context.lineTo(50, 10);
context.lineTo(90, 40);
context.lineTo(70, 40);
context.lineTo(70, 90);
context.lineTo(30, 90);
context.lineTo(30, 40);
context.closePath();
context.stroke();
context.save();
var refImage = context.getImageData(0, 0, 100, 100);
assert_equals(40000, refImage.data.length, "ImageData.data.length is 40000");
var original = document.getElementById('original');
var o_context = original.getContext('2d');
o_context.fillStyle = 'white';
o_context.fillRect(0, 0, 100, 100);
o_context.putImageData(refImage, 0, 0, 0, 0, 100, 100);
context.beginPath();
context.moveTo(5, 40);
context.lineTo(50, 5);
context.lineTo(95, 40);
context.lineTo(95, 45);
context.lineTo(75, 45);
context.lineTo(75, 95);
context.lineTo(25, 95);
context.lineTo(25, 45);
context.lineTo(5, 45);
context.closePath();
context.drawFocusIfNeeded(element);
var ringImage = context.getImageData(0, 0, 100, 100);
assert_equals(40000, ringImage.data.length, "ImageData.data.length is 40000");
// make sure refImage and ringImage are different
var length = 40000;
var index = length;
var identical = true;
while (--index > 0) {
if (refImage.data[index] != ringImage.data[index]) identical = false;
}
assert_false(identical, "A focus ring appears in the canvas");
}, 'drawFocusIfNeeded does draw a focus ring if the element is in focus.');
</script>
<div id="log"></div>
</body>
</html>