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twbs--bootstrap/js/affix.js
2013-12-08 12:44:14 +02:00

126 lines
3.8 KiB
JavaScript

/* ========================================================================
* Bootstrap: affix.js v3.0.3
* http://getbootstrap.com/javascript/#affix
* ========================================================================
* Copyright 2013 Twitter, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* ======================================================================== */
+function ($) { 'use strict';
// AFFIX CLASS DEFINITION
// ======================
var Affix = function (element, options) {
this.options = $.extend({}, Affix.DEFAULTS, options)
this.$window = $(window)
.on('scroll.bs.affix.data-api', $.proxy(this.checkPosition, this))
.on('click.bs.affix.data-api', $.proxy(this.checkPositionWithEventLoop, this))
this.$element = $(element)
this.affixed =
this.unpin = null
this.checkPosition()
}
Affix.RESET = 'affix affix-top affix-bottom'
Affix.DEFAULTS = {
offset: 0
}
Affix.prototype.checkPositionWithEventLoop = function () {
setTimeout($.proxy(this.checkPosition, this), 1)
}
Affix.prototype.checkPosition = function () {
if (!this.$element.is(':visible')) return
var scrollHeight = $(document).height()
var scrollTop = this.$window.scrollTop()
var position = this.$element.offset()
var offset = this.options.offset
var offsetTop = offset.top
var offsetBottom = offset.bottom
if (typeof offset != 'object') offsetBottom = offsetTop = offset
if (typeof offsetTop == 'function') offsetTop = offset.top()
if (typeof offsetBottom == 'function') offsetBottom = offset.bottom()
var affix = this.unpin != null && (scrollTop + this.unpin <= position.top) ? false :
offsetBottom != null && (position.top + this.$element.height() >= scrollHeight - offsetBottom) ? 'bottom' :
offsetTop != null && (scrollTop <= offsetTop) ? 'top' : false
if (this.affixed === affix) return
if (this.unpin) this.$element.css('top', '')
this.affixed = affix
this.unpin = affix == 'bottom' ? position.top - scrollTop : null
this.$element.removeClass(Affix.RESET).addClass('affix' + (affix ? '-' + affix : ''))
if (affix == 'bottom') {
this.$element.offset({ top: document.body.offsetHeight - offsetBottom - this.$element.height() })
}
}
// AFFIX PLUGIN DEFINITION
// =======================
var old = $.fn.affix
$.fn.affix = function (option) {
return this.each(function () {
var $this = $(this)
var data = $this.data('bs.affix')
var options = typeof option == 'object' && option
if (!data) $this.data('bs.affix', (data = new Affix(this, options)))
if (typeof option == 'string') data[option]()
})
}
$.fn.affix.Constructor = Affix
// AFFIX NO CONFLICT
// =================
$.fn.affix.noConflict = function () {
$.fn.affix = old
return this
}
// AFFIX DATA-API
// ==============
$(window).on('load', function () {
$('[data-spy="affix"]').each(function () {
var $spy = $(this)
var data = $spy.data()
data.offset = data.offset || {}
if (data.offsetBottom) data.offset.bottom = data.offsetBottom
if (data.offsetTop) data.offset.top = data.offsetTop
$spy.affix(data)
})
})
}(jQuery);