查看文件: scrollspy.min.js

大小: 2.16 KB

类型: application/javascript

!function($,window,document,undefined){$.fn.extend({scrollspy:function(options){var defaults={namespace:"scrollspy",activeClass:"active",animate:!1,duration:1e3,offset:0,container:window,replaceState:!1};options=$.extend({},defaults,options);var add=function(ex1,ex2){return parseInt(ex1,10)+parseInt(ex2,10)},findElements=function(links){for(var elements=[],i=0;i<links.length;i++){var link=links[i],hash=$(link).attr("href"),element=$(hash);if(element.length>0){var top=Math.floor(element.offset().top),bottom=top+Math.floor(element.outerHeight());elements.push({element:element,hash:hash,top:top,bottom:bottom})}}return elements},findLink=function(links,hash){for(var i=0;i<links.length;i++){var link=$(links[i]);if(link.attr("href")===hash)return link}},resetClasses=function(links){for(var i=0;i<links.length;i++)$(links[i]).parent().removeClass(options.activeClass)},scrollArea="";return this.each(function(){for(var element=this,container=$(options.container),links=$(element).find("a"),i=0;i<links.length;i++){var link=links[i];$(link).on("click",function(e){var target=$(this).attr("href"),$target=$(target);if($target.length>0){var top=add($target.offset().top,options.offset);options.animate?$("html, body").animate({scrollTop:top},options.duration):window.scrollTo(0,top),e.preventDefault()}})}resetClasses(links);var elements=findElements(links),trackChanged=function(){for(var link,position={top:add($(this).scrollTop(),Math.abs(options.offset)),left:$(this).scrollLeft()},i=0;i<elements.length;i++){var current=elements[i];if(position.top>=current.top&&position.top<current.bottom){var hash=current.hash;if(link=findLink(links,hash)){options.onChange&&scrollArea!==hash&&(options.onChange(current.element,$(element),position),scrollArea=hash),options.replaceState&&history.replaceState({},"","/"+hash),resetClasses(links),link.parent().addClass(options.activeClass);break}}}!link&&"exit"!==scrollArea&&options.onExit&&(options.onExit($(element),position),resetClasses(links),scrollArea="exit",options.replaceState&&history.replaceState({},"","/"))};container.bind("scroll."+options.namespace,function(){trackChanged()}),$(document).ready(function(e){trackChanged()})})}})}(jQuery,window,document);