https://www.goodyear.com.sg/wp-content/themes/hattframework/js/jquery.sticky.js

1// Sticky Plugin v1.0.2 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: 16/04/2015
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 slice = Array.prototype.slice; // save ref to original slice()
15    var splice = Array.prototype.splice; // save ref to original slice()
16
17    var defaults = {
18            topSpacing: 0,
19            bottomSpacing: 0,
20            className: 'is-sticky',
21            wrapperClassName: 'sticky-wrapper',
22            center: false,
23            getWidthFrom: '',
24            widthFromWrapper: true, // works only when .getWidthFrom is empty
25            responsiveWidth: false
26        },
27        $window = $(window),
28        $document = $(document),
29        sticked = [],
30        windowHeight = $window.height(),
31        scroller = function() {
32            var scrollTop = $window.scrollTop(),
33                documentHeight = $document.height(),
34                dwh = documentHeight - windowHeight,
35                extra = (scrollTop > dwh) ? dwh - scrollTop : 0;
36
37            for (var i = 0; i < sticked.length; i++) {
38                var s = sticked[i],
39                    elementTop = s.stickyWrapper.offset().top,
40                    etse = elementTop - s.topSpacing - extra;
41
42                if (scrollTop <= etse) {
43                    if (s.currentTop !== null) {
44                        s.stickyElement
45                            .css({
46                                'width': '',
47                                'position': '',
48                                'top': ''
49                            });
50                        s.stickyElement.parent().removeClass(s.className);
51                        s.stickyElement.trigger('sticky-end', [s]);
52                        s.currentTop = null;
53                    }
54                }
55                else {
56                    var newTop = documentHeight - s.stickyElement.outerHeight()
57                        - s.topSpacing - s.bottomSpacing - scrollTop - extra;
58                    if (newTop < 0) {
59                        newTop = newTop + s.topSpacing;
60                    } else {
61                        newTop = s.topSpacing;
62                    }
63                    if (s.currentTop != newTop) {
64                        var newWidth;
65                        if ( s.getWidthFrom ) {
66                            newWidth = $(s.getWidthFrom).width() || null;
67                        }
68                        else if(s.widthFromWrapper) {
69                            newWidth = s.stickyWrapper.width();
70                        }
71                        if ( newWidth == null ) {
72                            newWidth = s.stickyElement.width();
73                        }
74                        s.stickyElement
75                            .css('width', newWidth)
76                            .css('position', 'fixed')
77                            .css('top', newTop);
78
79                        s.stickyElement.parent().addClass(s.className);
80
81                        if (s.currentTop === null) {
82                            s.stickyElement.trigger('sticky-start', [s]);
83                        } else {
84                            // sticky is started but it have to be repositioned
85                            s.stickyElement.trigger('sticky-update', [s]);
86                        }
87
88                        if (s.currentTop === s.topSpacing && s.currentTop > newTop || s.currentTop === null && newTop < s.topSpacing) {
89                            // just reached bottom || just started to stick but bottom is already reached
90                            s.stickyElement.trigger('sticky-bottom-reached', [s]);
91                        } else if(s.currentTop !== null && newTop === s.topSpacing && s.currentTop < newTop) {
92                            // sticky is started && sticked at topSpacing && overflowing from top just finished
93                            s.stickyElement.trigger('sticky-bottom-unreached', [s]);
94                        }
95
96                        s.currentTop = newTop;
97                    }
98                }
99            }
100        },
101        resizer = function() {
102            windowHeight = $window.height();
103
104            for (var i = 0; i < sticked.length; i++) {
105                var s = sticked[i];
106                var newWidth = null;
107                if ( s.getWidthFrom ) {
108                    if ( s.responsiveWidth === true ) {
109                        newWidth = $(s.getWidthFrom).width();
110                    }
111                }
112                else if(s.widthFromWrapper) {
113                    newWidth = s.stickyWrapper.width();
114                }
115                if ( newWidth != null ) {
116                    s.stickyElement.css('width', newWidth);
117                }
118            }
119        },
120        methods = {
121            init: function(options) {
122                var o = $.extend({}, defaults, options);
123                return this.each(function() {
124                    var stickyElement = $(this);
125
126                    var stickyId = stickyElement.attr('id');
127                    var stickyHeight = stickyElement.outerHeight();
128                    var wrapperId = stickyId ? stickyId + '-' + defaults.wrapperClassName : defaults.wrapperClassName
129                    var wrapper = $('<div></div>')
130                        .attr('id', wrapperId)
131                        .addClass(o.wrapperClassName);
132
133                    stickyElement.wrapAll(wrapper);
134
135                    var stickyWrapper = stickyElement.parent();
136
137                    if (o.center) {
138                        stickyWrapper.css({width:stickyElement.outerWidth(),marginLeft:"auto",marginRight:"auto"});
139                    }
140
141                    if (stickyElement.css("float") == "right") {
142                        stickyElement.css({"float":"none"}).parent().css({"float":"right"});
143                    }
144
145                    stickyWrapper.css('height', stickyHeight);
146
147                    o.stickyElement = stickyElement;
148                    o.stickyWrapper = stickyWrapper;
149                    o.currentTop    = null;
150
151                    sticked.push(o);
152                });
153            },
154            update: scroller,
155            unstick: function(options) {
156                return this.each(function() {
157                    var that = this;
158                    var unstickyElement = $(that);
159
160                    var removeIdx = -1;
161                    var i = sticked.length;
162                    while ( i-- > 0 )
163                    {
164                        if (sticked[i].stickyElement.get(0) === that)
165                        {
166                            splice.call(sticked,i,1);
167                            removeIdx = i;
168                        }
169                    }
170                    if(removeIdx != -1)
171                    {
172                        unstickyElement.unwrap();
173                        unstickyElement
174                            .css({
175                                'width': '',
176                                'position': '',
177                                'top': '',
178                                'float': ''
179                            })
180                        ;
181                    }
182                });
183            }
184        };
185
186    // should be more efficient than using $window.scroll(scroller) and $window.resize(resizer):
187    if (window.addEventListener) {
188        window.addEventListener('scroll', scroller, false);
189        window.addEventListener('resize', resizer, false);
190    } else if (window.attachEvent) {
191        window.attachEvent('onscroll', scroller);
192        window.attachEvent('onresize', resizer);
193    }
194
195    $.fn.sticky = function(method) {
196        if (methods[method]) {
197            return methods[method].apply(this, slice.call(arguments, 1));
198        } else if (typeof method === 'object' || !method ) {
199            return methods.init.apply( this, arguments );
200        } else {
201            $.error('Method ' + method + ' does not exist on jQuery.sticky');
202        }
203    };
204
205    $.fn.unstick = function(method) {
206        if (methods[method]) {
207            return methods[method].apply(this, slice.call(arguments, 1));
208        } else if (typeof method === 'object' || !method ) {
209            return methods.unstick.apply( this, arguments );
210        } else {
211            $.error('Method ' + method + ' does not exist on jQuery.sticky');
212        }
213
214    };
215    $(function() {
216        setTimeout(scroller, 0);
217    });
218})(jQuery);