Blame view
static/plugins/webshim-gh-pages/js-webshim/dev/shims/matchMedia.js
4.45 KB
831eac332
add file
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 |
/*! matchMedia() polyfill - Test a CSS media type/query in JS. Authors & copyright (c) 2012: Scott Jehl, Paul Irish, Nicholas Zakas, David Knight. Dual MIT/BSD license */
window.matchMedia || (window.matchMedia = function() {
"use strict";
// For browsers that support matchMedium api such as IE 9 and webkit
var styleMedia = (window.styleMedia || window.media);
// For those that don't support matchMedium
if (!styleMedia) {
var style = document.createElement('style'),
script = document.getElementsByTagName('script')[0],
info = null;
style.type = 'text/css';
style.id = 'matchmediajs-test';
script.parentNode.insertBefore(style, script);
// 'style.currentStyle' is used by IE <= 8 and 'window.getComputedStyle' for all other browsers
info = ('getComputedStyle' in window) && window.getComputedStyle(style, null) || style.currentStyle;
styleMedia = {
matchMedium: function(media) {
var text = '@media ' + media + '{ #matchmediajs-test { width: 1px; } }';
// 'style.styleSheet' is used by IE <= 8 and 'style.textContent' for all other browsers
if (style.styleSheet) {
style.styleSheet.cssText = text;
} else {
style.textContent = text;
}
// Test if media query is true or false
return info.width === '1px';
}
};
}
return function(media) {
return {
matches: styleMedia.matchMedium(media || 'all'),
media: media || 'all'
};
};
}());
/*! matchMedia() polyfill addListener/removeListener extension. Author & copyright (c) 2012: Scott Jehl. Dual MIT/BSD license */
(function(){
// Bail out for browsers that have addListener support
if (window.matchMedia && window.matchMedia('all').addListener) {
return false;
}
var localMatchMedia = window.matchMedia,
hasMediaQueries = localMatchMedia('only all').matches,
isListening = false,
timeoutID = 0, // setTimeout for debouncing 'handleChange'
queries = [], // Contains each 'mql' and associated 'listeners' if 'addListener' is used
handleChange = function(evt) {
// Debounce
clearTimeout(timeoutID);
timeoutID = setTimeout(function() {
for (var i = 0, il = queries.length; i < il; i++) {
var mql = queries[i].mql,
listeners = queries[i].listeners || [],
matches = localMatchMedia(mql.media).matches;
// Update mql.matches value and call listeners
// Fire listeners only if transitioning to or from matched state
if (matches !== mql.matches) {
mql.matches = matches;
for (var j = 0, jl = listeners.length; j < jl; j++) {
listeners[j].call(window, mql);
}
}
}
}, 30);
};
window.matchMedia = function(media) {
var mql = localMatchMedia(media),
listeners = [],
index = 0;
mql.addListener = function(listener) {
// Changes would not occur to css media type so return now (Affects IE <= 8)
if (!hasMediaQueries) {
return;
}
// Set up 'resize' listener for browsers that support CSS3 media queries (Not for IE <= 8)
// There should only ever be 1 resize listener running for performance
if (!isListening) {
isListening = true;
window.addEventListener('resize', handleChange, true);
}
// Push object only if it has not been pushed already
if (index === 0) {
index = queries.push({
mql : mql,
listeners : listeners
});
}
listeners.push(listener);
};
mql.removeListener = function(listener) {
for (var i = 0, il = listeners.length; i < il; i++){
if (listeners[i] === listener){
listeners.splice(i, 1);
}
}
};
return mql;
};
}());
webshim.isReady('matchMedia', true);
|