<!DOCTYPE html>
<html>
<!--
Copyright The Closure Library Authors. All Rights Reserved.
Use of this source code is governed by the Apache License, Version 2.0.
See the COPYING file for details.
-->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Color Contrast Test</title>
<style type="text/css" media="screen">
#preview {
margin-left: 1em;
padding: 0.5em 1em;
background: #ccc;
}
</style>
</head>
<body>
<script type="text/javascript" src="../base.js"></script>
<p>
#<input type="text" value="cccccc" id="color" size="6" maxlength="6">
<input
type="button"
value="Black or White?"
id="submit"
onclick="blackOrWhite()">
<span id="preview">This text should be readable</span>
</p>
<p>(Only choosing from black and white.)</p>
<script type="text/javascript" charset="utf-8">
goog.require('goog.color');
function blackOrWhite() {
var colorInput = document.getElementById('color');
var previewElement = document.getElementById('preview');
var bgRgb = goog.color.hexToRgbStyle('#' + colorInput.value);
var bgRgbArr = goog.color.parseRgb(bgRgb);
var bestColor = goog.color.highContrast(
bgRgbArr, [[0, 0, 0], [255, 255, 255]]);
var bestColorHex = goog.color.rgbArrayToHex(bestColor);
console.info(bestColorHex + ' wins on sum');
previewElement.style.backgroundColor = '#' + colorInput.value;
previewElement.style.color = bestColorHex;
}
</script>
</body>
</html>