https://cm-vrsa.pt/includes/js/jquery.sticky.js

1// Sticky Plugin v1.0.0 for jQuery
2// =============
3// Author: Anthony Garand
4// Improvements by German M. Bravo (Kronuz) and Ruud Kamphuis (ruudk)
5// Improvements by Leonardo C. Daronco (daronco)
6// Created: 2/14/2011
7// Date: 2/12/2012
8// Website: http://labs.anthonygarand.com/sticky
9// Description: Makes an element on the page stick on the screen as you scroll
10//       It will only set the 'top' and 'position' of your element, you
11//       might need to adjust the width in some cases.
12
13(function ($) {
14    var defaults = {
15        topSpacing: 0,
16        bottomSpacing: 0,
17        className: 'is-sticky',
18        wrapperClassName: 'sticky-wrapper',
19        center: true,
20        getWidthFrom: '#mainheader'
21    },
22    $window = $(window),
23    $document = $(document),
24    sticked = [],
25    windowHeight = $window.height(),
26    scroller = function () {
27        var scrollTop = $window.scrollTop(),
28        documentHeight = $document.height(),
29        dwh = documentHeight - windowHeight,
30        extra = (scrollTop > dwh) ? dwh - scrollTop : 0;
31
32        for (var i = 0; i < sticked.length; i++) {
33            var s = sticked[i],
34          elementTop = s.stickyWrapper.offset().top,
35          etse = elementTop - s.topSpacing - extra;
36
37            if (scrollTop <= etse) {
38                if (s.currentTop !== null) {
39                    s.stickyElement
40              .css('position', '')
41              .css('top', '');
42                    s.stickyElement.parent().removeClass(s.className);
43                    s.currentTop = null;
44                }
45            }
46            else {
47                var newTop = documentHeight - s.stickyElement.outerHeight()
48            - s.topSpacing - s.bottomSpacing - scrollTop - extra;
49                if (newTop < 0) {
50                    newTop = newTop + s.topSpacing;
51                } else {
52                    newTop = s.topSpacing;
53                }
54                if (s.currentTop != newTop) {
55                    s.stickyElement
56              .css('position', 'fixed')
57              .css('top', newTop);
58
59                    if (typeof s.getWidthFrom !== 'undefined') {
60                        s.stickyElement.css('width', $(s.getWidthFrom).width());
61                    }
62
63                    s.stickyElement.parent().addClass(s.className);
64                    s.currentTop = newTop;
65                }
66            }
67        }
68    },
69    resizer = function () {
70        windowHeight = $window.height();
71    },
72    methods = {
73        init: function (options) {
74            var o = $.extend({}, defaults, options);
75            return this.each(function () {
76                var stickyElement = $(this);
77
78                var stickyId = stickyElement.attr('id');
79                var wrapperId = stickyId ? stickyId + '-' + defaults.wrapperClassName : defaults.wrapperClassName
80                var wrapper = $('<div></div>')
81            .attr('id', stickyId + '-sticky-wrapper')
82            .addClass(o.wrapperClassName);
83                stickyElement.wrapAll(wrapper);
84
85                if (o.center) {
86                    //stickyElement.parent().css({ width: stickyElement.outerWidth(), marginLeft: "auto", marginRight: "auto" });
87                    stickyElement.parent().css({ width: "100%", marginLeft: "auto", marginRight: "auto" });
88                }
89
90                if (stickyElement.css("float") == "right") {
91                    stickyElement.css({ "float": "none" }).parent().css({ "float": "right" });
92                }
93
94                var stickyWrapper = stickyElement.parent();
95                stickyWrapper.css('height', stickyElement.outerHeight());
96                sticked.push({
97                    topSpacing: o.topSpacing,
98                    bottomSpacing: o.bottomSpacing,
99                    stickyElement: stickyElement,
100                    currentTop: null,
101                    stickyWrapper: stickyWrapper,
102                    className: o.className,
103                    getWidthFrom: o.getWidthFrom
104                });
105            });
106        },
107        update: scroller,
108        unstick: function (options) {
109            return this.each(function () {
110                var unstickyElement = $(this);
111
112                var removeIdx = -1;
113                for (var i = 0; i < sticked.length; i++) {
114                    if (sticked[i].stickyElement.get(0) == unstickyElement.get(0)) {
115                        removeIdx = i;
116                    }
117                }
118                if (removeIdx != -1) {
119                    sticked.splice(removeIdx, 1);
120                    unstickyElement.unwrap();
121                    unstickyElement.removeAttr('style');
122                }
123            });
124        }
125    };
126
127    // should be more efficient than using $window.scroll(scroller) and $window.resize(resizer):
128    if (window.addEventListener) {
129        window.addEventListener('scroll', scroller, false);
130        window.addEventListener('resize', resizer, false);
131    } else if (window.attachEvent) {
132        window.attachEvent('onscroll', scroller);
133        window.attachEvent('onresize', resizer);
134    }
135
136    $.fn.sticky = function (method) {
137        if (methods[method]) {
138            return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
139        } else if (typeof method === 'object' || !method) {
140            return methods.init.apply(this, arguments);
141        } else {
142            $.error('Method ' + method + ' does not exist on jQuery.sticky');
143        }
144    };
145
146    $.fn.unstick = function (method) {
147        if (methods[method]) {
148            return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
149        } else if (typeof method === 'object' || !method) {
150            return methods.unstick.apply(this, arguments);
151        } else {
152            $.error('Method ' + method + ' does not exist on jQuery.sticky');
153        }
154
155    };
156    $(function () {
157        setTimeout(scroller, 0);
158    });

159})(jQuery);