https://creeksidechiro.com/themes/common/javascripts/smb/jquery.responsive-helper.js?v.4a2bae

1/*
2 * Responsive Layout helper
3 */
4ResponsiveHelper = (function($) {
5	// init variables
6	var handlers = [],
7		prevWinWidth,
8		win = $(window),
9		nativeMatchMedia = false;
10
11	// detect match media support
12	if (window.matchMedia) {
13		if (window.Window && window.matchMedia === Window.prototype.matchMedia) {
14			nativeMatchMedia = true;
15		} else if (window.matchMedia.toString().indexOf('native') > -1) {
16			nativeMatchMedia = true;
17		}
18	}
19
20	// prepare resize handler
21	function resizeHandler() {
22		var winWidth = win.width();
23		if (winWidth !== prevWinWidth) {
24			prevWinWidth = winWidth;
25
26			// loop through range groups
27			$.each(handlers, function(index, rangeObject) {
28				// disable current active area if needed
29				$.each(rangeObject.data, function(property, item) {
30					if (item.currentActive && !matchRange(item.range[0], item.range[1])) {
31						item.currentActive = false;
32						if (typeof item.disableCallback === 'function') {
33							item.disableCallback();
34						}
35					}
36				});
37
38				// enable areas that match current width
39				$.each(rangeObject.data, function(property, item) {
40					if (!item.currentActive && matchRange(item.range[0], item.range[1])) {
41						// make callback
42						item.currentActive = true;
43						if (typeof item.enableCallback === 'function') {
44							item.enableCallback();
45						}
46					}
47				});
48			});
49		}
50	}
51	win.bind('load resize orientationchange', resizeHandler);
52
53	// test range
54	function matchRange(r1, r2) {
55		var mediaQueryString = '';
56		if (r1 > 0) {
57			mediaQueryString += '(min-width: ' + r1 + 'px)';
58		}
59		if (r2 < Infinity) {
60			mediaQueryString += (mediaQueryString ? ' and ' : '') + '(max-width: ' + r2 + 'px)';
61		}
62		return matchQuery(mediaQueryString, r1, r2);
63	}
64
65	// media query function
66	function matchQuery(query, r1, r2) {
67		if (window.matchMedia && nativeMatchMedia) {
68			return matchMedia(query).matches;
69		} else if (window.styleMedia) {
70			return styleMedia.matchMedium(query);
71		} else if (window.media) {
72			return media.matchMedium(query);
73		} else {
74			return prevWinWidth >= r1 && prevWinWidth <= r2;
75		}
76	}
77
78	// range parser
79	function parseRange(rangeStr) {
80		var rangeData = rangeStr.split('..');
81		var x1 = parseInt(rangeData[0], 10) || -Infinity;
82		var x2 = parseInt(rangeData[1], 10) || Infinity;
83		return [x1, x2].sort(function(a, b) {
84			return a - b;
85		});
86	}
87
88	// export public functions
89	return {
90		addRange: function(ranges) {
91			// parse data and add items to collection
92			var result = { data: {} };
93			$.each(ranges, function(property, data) {
94				result.data[property] = {
95					range: parseRange(property),
96					enableCallback: data.on,
97					disableCallback: data.off
98				};
99			});
100			handlers.push(result);
101
102			// call resizeHandler to recalculate all events
103			prevWinWidth = null;
104			resizeHandler();
105		}
106	};
107}(jQuery));