https://www.middleeasteye.net/themes/mee_subtheme/bootstrap/assets/javascripts/bootstrap/affix.js?tltchd

1/* ========================================================================
2 * Bootstrap: affix.js v3.3.7
3 * http://getbootstrap.com/javascript/#affix
4 * ========================================================================
5 * Copyright 2011-2016 Twitter, Inc.
6 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
7 * ======================================================================== */
8
9
10+function ($) {
11  'use strict';
12
13  // AFFIX CLASS DEFINITION
14  // ======================
15
16  var Affix = function (element, options) {
17    this.options = $.extend({}, Affix.DEFAULTS, options)
18
19    this.$target = $(this.options.target)
20      .on('scroll.bs.affix.data-api', $.proxy(this.checkPosition, this))
21      .on('click.bs.affix.data-api',  $.proxy(this.checkPositionWithEventLoop, this))
22
23    this.$element     = $(element)
24    this.affixed      = null
25    this.unpin        = null
26    this.pinnedOffset = null
27
28    this.checkPosition()
29  }
30
31  Affix.VERSION  = '3.3.7'
32
33  Affix.RESET    = 'affix affix-top affix-bottom'
34
35  Affix.DEFAULTS = {
36    offset: 0,
37    target: window
38  }
39
40  Affix.prototype.getState = function (scrollHeight, height, offsetTop, offsetBottom) {
41    var scrollTop    = this.$target.scrollTop()
42    var position     = this.$element.offset()
43    var targetHeight = this.$target.height()
44
45    if (offsetTop != null && this.affixed == 'top') return scrollTop < offsetTop ? 'top' : false
46
47    if (this.affixed == 'bottom') {
48      if (offsetTop != null) return (scrollTop + this.unpin <= position.top) ? false : 'bottom'
49      return (scrollTop + targetHeight <= scrollHeight - offsetBottom) ? false : 'bottom'
50    }
51
52    var initializing   = this.affixed == null
53    var colliderTop    = initializing ? scrollTop : position.top
54    var colliderHeight = initializing ? targetHeight : height
55
56    if (offsetTop != null && scrollTop <= offsetTop) return 'top'
57    if (offsetBottom != null && (colliderTop + colliderHeight >= scrollHeight - offsetBottom)) return 'bottom'
58
59    return false
60  }
61
62  Affix.prototype.getPinnedOffset = function () {
63    if (this.pinnedOffset) return this.pinnedOffset
64    this.$element.removeClass(Affix.RESET).addClass('affix')
65    var scrollTop = this.$target.scrollTop()
66    var position  = this.$element.offset()
67    return (this.pinnedOffset = position.top - scrollTop)
68  }
69
70  Affix.prototype.checkPositionWithEventLoop = function () {
71    setTimeout($.proxy(this.checkPosition, this), 1)
72  }
73
74  Affix.prototype.checkPosition = function () {
75    if (!this.$element.is(':visible')) return
76
77    var height       = this.$element.height()
78    var offset       = this.options.offset
79    var offsetTop    = offset.top
80    var offsetBottom = offset.bottom
81    var scrollHeight = Math.max($(document).height(), $(document.body).height())
82
83    if (typeof offset != 'object')         offsetBottom = offsetTop = offset
84    if (typeof offsetTop == 'function')    offsetTop    = offset.top(this.$element)
85    if (typeof offsetBottom == 'function') offsetBottom = offset.bottom(this.$element)
86
87    var affix = this.getState(scrollHeight, height, offsetTop, offsetBottom)
88
89    if (this.affixed != affix) {
90      if (this.unpin != null) this.$element.css('top', '')
91
92      var affixType = 'affix' + (affix ? '-' + affix : '')
93      var e         = $.Event(affixType + '.bs.affix')
94
95      this.$element.trigger(e)
96
97      if (e.isDefaultPrevented()) return
98
99      this.affixed = affix
100      this.unpin = affix == 'bottom' ? this.getPinnedOffset() : null
101
102      this.$element
103        .removeClass(Affix.RESET)
104        .addClass(affixType)
105        .trigger(affixType.replace('affix', 'affixed') + '.bs.affix')
106    }
107
108    if (affix == 'bottom') {
109      this.$element.offset({
110        top: scrollHeight - height - offsetBottom
111      })
112    }
113  }
114
115
116  // AFFIX PLUGIN DEFINITION
117  // =======================
118
119  function Plugin(option) {
120    return this.each(function () {
121      var $this   = $(this)
122      var data    = $this.data('bs.affix')
123      var options = typeof option == 'object' && option
124
125      if (!data) $this.data('bs.affix', (data = new Affix(this, options)))
126      if (typeof option == 'string') data[option]()
127    })
128  }
129
130  var old = $.fn.affix
131
132  $.fn.affix             = Plugin
133  $.fn.affix.Constructor = Affix
134
135
136  // AFFIX NO CONFLICT
137  // =================
138
139  $.fn.affix.noConflict = function () {
140    $.fn.affix = old
141    return this
142  }
143
144
145  // AFFIX DATA-API
146  // ==============
147
148  $(window).on('load', function () {
149    $('[data-spy="affix"]').each(function () {
150      var $spy = $(this)
151      var data = $spy.data()
152
153      data.offset = data.offset || {}
154
155      if (data.offsetBottom != null) data.offset.bottom = data.offsetBottom
156      if (data.offsetTop    != null) data.offset.top    = data.offsetTop
157
158      Plugin.call($spy, data)
159    })
160  })
161
162}(jQuery);