scrollspy.js 4.2KB

    /* ======================================================================== * Bootstrap: scrollspy.js v3.1.1 * http://getbootstrap.com/javascript/#scrollspy * ======================================================================== * Copyright 2011-2014 Twitter, Inc. * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE) * ======================================================================== */ +function ($) { 'use strict'; // SCROLLSPY CLASS DEFINITION // ========================== function ScrollSpy(element, options) { var href var process = $.proxy(this.process, this) this.$element = $(element).is('body') ? $(window) : $(element) this.$body = $('body') this.$scrollElement = this.$element.on('scroll.bs.scroll-spy.data-api', process) this.options = $.extend({}, ScrollSpy.DEFAULTS, options) this.selector = (this.options.target || ((href = $(element).attr('href')) && href.replace(/.*(?=#[^\s]+$)/, '')) //strip for ie7 || '') + ' .nav li > a' this.offsets = $([]) this.targets = $([]) this.activeTarget = null this.refresh() this.process() } ScrollSpy.DEFAULTS = { offset: 10 } ScrollSpy.prototype.refresh = function () { var offsetMethod = this.$element[0] == window ? 'offset' : 'position' this.offsets = $([]) this.targets = $([]) var self = this var $targets = this.$body .find(this.selector) .map(function () { var $el = $(this) var href = $el.data('target') || $el.attr('href') var $href = /^#./.test(href) && $(href) return ($href && $href.length && $href.is(':visible') && [[ $href[offsetMethod]().top + (!$.isWindow(self.$scrollElement.get(0)) && self.$scrollElement.scrollTop()), href ]]) || null }) .sort(function (a, b) { return a[0] - b[0] }) .each(function () { self.offsets.push(this[0]) self.targets.push(this[1]) }) } ScrollSpy.prototype.process = function () { var scrollTop = this.$scrollElement.scrollTop() + this.options.offset var scrollHeight = this.$scrollElement[0].scrollHeight || this.$body[0].scrollHeight var maxScroll = scrollHeight - this.$scrollElement.height() var offsets = this.offsets var targets = this.targets var activeTarget = this.activeTarget var i if (scrollTop >= maxScroll) { return activeTarget != (i = targets.last()[0]) && this.activate(i) } if (activeTarget && scrollTop <= offsets[0]) { return activeTarget != (i = targets[0]) && this.activate(i) } for (i = offsets.length; i--;) { activeTarget != targets[i] && scrollTop >= offsets[i] && (!offsets[i + 1] || scrollTop <= offsets[i + 1]) && this.activate( targets[i] ) } } ScrollSpy.prototype.activate = function (target) { this.activeTarget = target $(this.selector) .parentsUntil(this.options.target, '.active') .removeClass('active') var selector = this.selector + '[data-target="' + target + '"],' + this.selector + '[href="' + target + '"]' var active = $(selector) .parents('li') .addClass('active') if (active.parent('.dropdown-menu').length) { active = active .closest('li.dropdown') .addClass('active') } active.trigger('activate.bs.scrollspy') } // SCROLLSPY PLUGIN DEFINITION // =========================== var old = $.fn.scrollspy $.fn.scrollspy = function (option) { return this.each(function () { var $this = $(this) var data = $this.data('bs.scrollspy') var options = typeof option == 'object' && option if (!data) $this.data('bs.scrollspy', (data = new ScrollSpy(this, options))) if (typeof option == 'string') data[option]() }) } $.fn.scrollspy.Constructor = ScrollSpy // SCROLLSPY NO CONFLICT // ===================== $.fn.scrollspy.noConflict = function () { $.fn.scrollspy = old return this } // SCROLLSPY DATA-API // ================== $(window).on('load', function () { $('[data-spy="scroll"]').each(function () { var $spy = $(this) $spy.scrollspy($spy.data()) }) }) }(jQuery);