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1 /* ========================================================== |
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2 * bootstrap-affix.js v2.3.1 |
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3 * http://twitter.github.com/bootstrap/javascript.html#affix |
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4 * ========================================================== |
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5 * Copyright 2012 Twitter, Inc. |
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6 * |
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7 * Licensed under the Apache License, Version 2.0 (the "License"); |
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8 * you may not use this file except in compliance with the License. |
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9 * You may obtain a copy of the License at |
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10 * |
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11 * http://www.apache.org/licenses/LICENSE-2.0 |
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12 * |
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13 * Unless required by applicable law or agreed to in writing, software |
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14 * distributed under the License is distributed on an "AS IS" BASIS, |
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15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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16 * See the License for the specific language governing permissions and |
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17 * limitations under the License. |
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18 * ========================================================== */ |
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19 |
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20 |
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21 !function ($) { |
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22 |
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23 "use strict"; // jshint ;_; |
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24 |
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25 |
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26 /* AFFIX CLASS DEFINITION |
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27 * ====================== */ |
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28 |
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29 var Affix = function (element, options) { |
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30 this.options = $.extend({}, $.fn.affix.defaults, options) |
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31 this.$window = $(window) |
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32 .on('scroll.affix.data-api', $.proxy(this.checkPosition, this)) |
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33 .on('click.affix.data-api', $.proxy(function () { setTimeout($.proxy(this.checkPosition, this), 1) }, this)) |
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34 this.$element = $(element) |
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35 this.checkPosition() |
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36 } |
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37 |
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38 Affix.prototype.checkPosition = function () { |
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39 if (!this.$element.is(':visible')) return |
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40 |
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41 var scrollHeight = $(document).height() |
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42 , scrollTop = this.$window.scrollTop() |
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43 , position = this.$element.offset() |
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44 , offset = this.options.offset |
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45 , offsetBottom = offset.bottom |
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46 , offsetTop = offset.top |
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47 , reset = 'affix affix-top affix-bottom' |
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48 , affix |
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49 |
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50 if (typeof offset != 'object') offsetBottom = offsetTop = offset |
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51 if (typeof offsetTop == 'function') offsetTop = offset.top() |
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52 if (typeof offsetBottom == 'function') offsetBottom = offset.bottom() |
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53 |
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54 affix = this.unpin != null && (scrollTop + this.unpin <= position.top) ? |
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55 false : offsetBottom != null && (position.top + this.$element.height() >= scrollHeight - offsetBottom) ? |
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56 'bottom' : offsetTop != null && scrollTop <= offsetTop ? |
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57 'top' : false |
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58 |
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59 if (this.affixed === affix) return |
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60 |
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61 this.affixed = affix |
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62 this.unpin = affix == 'bottom' ? position.top - scrollTop : null |
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63 |
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64 this.$element.removeClass(reset).addClass('affix' + (affix ? '-' + affix : '')) |
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65 } |
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66 |
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67 |
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68 /* AFFIX PLUGIN DEFINITION |
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69 * ======================= */ |
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70 |
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71 var old = $.fn.affix |
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72 |
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73 $.fn.affix = function (option) { |
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74 return this.each(function () { |
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75 var $this = $(this) |
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76 , data = $this.data('affix') |
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77 , options = typeof option == 'object' && option |
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78 if (!data) $this.data('affix', (data = new Affix(this, options))) |
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79 if (typeof option == 'string') data[option]() |
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80 }) |
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81 } |
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82 |
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83 $.fn.affix.Constructor = Affix |
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84 |
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85 $.fn.affix.defaults = { |
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86 offset: 0 |
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87 } |
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88 |
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89 |
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90 /* AFFIX NO CONFLICT |
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91 * ================= */ |
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92 |
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93 $.fn.affix.noConflict = function () { |
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94 $.fn.affix = old |
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95 return this |
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96 } |
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97 |
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98 |
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99 /* AFFIX DATA-API |
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100 * ============== */ |
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101 |
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102 $(window).on('load', function () { |
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103 $('[data-spy="affix"]').each(function () { |
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104 var $spy = $(this) |
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105 , data = $spy.data() |
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106 |
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107 data.offset = data.offset || {} |
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108 |
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109 data.offsetBottom && (data.offset.bottom = data.offsetBottom) |
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110 data.offsetTop && (data.offset.top = data.offsetTop) |
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111 |
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112 $spy.affix(data) |
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113 }) |
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114 }) |
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115 |
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116 |
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117 }(window.jQuery); |