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| 1 | +/* ======================================================================== |
| 2 | + * Bootstrap: affix.js v3.3.1 |
| 3 | + * http://getbootstrap.com/javascript/#affix |
| 4 | + * ======================================================================== |
| 5 | + * Copyright 2011-2014 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 = $(element) |
| 24 | + this.affixed = |
| 25 | + this.unpin = |
| 26 | + this.pinnedOffset = null |
| 27 | + |
| 28 | + this.checkPosition() |
| 29 | + } |
| 30 | + |
| 31 | + Affix.VERSION = '3.3.1' |
| 32 | + |
| 33 | + Affix.RESET = 'affix affix-top affix-bottom' |
| 34 | + |
| 35 | + Affix.DEFAULTS = { |
| 36 | + offset: 0, |
| 37 | + target: window |
| 38 | + } |
| 39 | + |
| 40 | + Affix.prototype.getState = function (scrollHeight, height, offsetTop, offsetBottom) { |
| 41 | + var scrollTop = this.$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 && colliderTop <= 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 = $('body').height() |
| 82 | + |
| 83 | + if (typeof offset != 'object') offsetBottom = offsetTop = offset |
| 84 | + if (typeof offsetTop == 'function') offsetTop = offset.top(this.$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); |
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