bootstrap-scrollspy.js

!function($){"use strict";function ScrollSpy(element,options){var process=$.proxy(this.process,this),$element=$(element).is("body")?$(window):$(element),href;this.options=$.extend({},$.fn.scrollspy.defaults,options),this.$scrollElement=$element.on("scroll.scroll-spy.data-api",process),this.selector=(this.options.target||(href=$(element).attr("href"))&&href.replace(/.*(?=#[^\s]+$)/,"")||"")+" .nav li > a",this.$body=$("body"),this.refresh(),this.process()}ScrollSpy.prototype={constructor:ScrollSpy,refresh:function(){var self=this;this.offsets=$([]),this.targets=$([]),this.$body.find(this.selector).map(function(){var $el=$(this),href=$el.data("target")||$el.attr("href"),$href=/^#\w/.test(href)&&$(href);return $href&&$href.length&&[[$href.position().top+(!$.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])})},process:function(){var scrollTop=this.$scrollElement.scrollTop()+this.options.offset,scrollHeight,maxScroll=(this.$scrollElement[0].scrollHeight||this.$body[0].scrollHeight)-this.$scrollElement.height(),offsets=this.offsets,targets=this.targets,activeTarget=this.activeTarget,i;if(scrollTop>=maxScroll)return activeTarget!=(i=targets.last()[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])},activate:function(target){var active,selector;this.activeTarget=target,$(this.selector).parent(".active").removeClass("active"),selector=this.selector+'[data-target="'+target+'"],'+this.selector+'[href="'+target+'"]',(active=$(selector).parent("li").addClass("active")).parent(".dropdown-menu").length&&(active=active.closest("li.dropdown").addClass("active")),active.trigger("activate")}};var old=$.fn.scrollspy;$.fn.scrollspy=function(option){return this.each(function(){var $this=$(this),data=$this.data("scrollspy"),options="object"==typeof option&&option;data||$this.data("scrollspy",data=new ScrollSpy(this,options)),"string"==typeof option&&data[option]()})},$.fn.scrollspy.Constructor=ScrollSpy,$.fn.scrollspy.defaults={offset:10},$.fn.scrollspy.noConflict=function(){return $.fn.scrollspy=old,this},$(window).on("load",function(){$('[data-spy="scroll"]').each(function(){var $spy=$(this);$spy.scrollspy($spy.data())})})}(window.jQuery);