向下滚动页面时,活动菜单项将更改。怎么做?
Answers:
快速示例:
// Cache selectors
var topMenu = $("#top-menu"),
    topMenuHeight = topMenu.outerHeight()+15,
    // All list items
    menuItems = topMenu.find("a"),
    // Anchors corresponding to menu items
    scrollItems = menuItems.map(function(){
      var item = $($(this).attr("href"));
      if (item.length) { return item; }
    });
// Bind to scroll
$(window).scroll(function(){
   // Get container scroll position
   var fromTop = $(this).scrollTop()+topMenuHeight;
   // Get id of current scroll item
   var cur = scrollItems.map(function(){
     if ($(this).offset().top < fromTop)
       return this;
   });
   // Get the id of the current element
   cur = cur[cur.length-1];
   var id = cur && cur.length ? cur[0].id : "";
   // Set/remove active class
   menuItems
     .parent().removeClass("active")
     .end().filter("[href='#"+id+"']").parent().addClass("active");
});
    只需检查我的代码和狙击和演示链接:
    // Basice Code keep it 
    $(document).ready(function () {
        $(document).on("scroll", onScroll);
        //smoothscroll
        $('a[href^="#"]').on('click', function (e) {
            e.preventDefault();
            $(document).off("scroll");
            $('a').each(function () {
                $(this).removeClass('active');
            })
            $(this).addClass('active');
            var target = this.hash,
                menu = target;
            $target = $(target);
            $('html, body').stop().animate({
                'scrollTop': $target.offset().top+2
            }, 500, 'swing', function () {
                window.location.hash = target;
                $(document).on("scroll", onScroll);
            });
        });
    });
// Use Your Class or ID For Selection 
    function onScroll(event){
        var scrollPos = $(document).scrollTop();
        $('#menu-center a').each(function () {
            var currLink = $(this);
            var refElement = $(currLink.attr("href"));
            if (refElement.position().top <= scrollPos && refElement.position().top + refElement.height() > scrollPos) {
                $('#menu-center ul li a').removeClass("active");
                currLink.addClass("active");
            }
            else{
                currLink.removeClass("active");
            }
        });
    }
    只是为了补充@Marcus Ekwall的答案。这样做只会获得锚链接。如果锚链接和常规链接混在一起,也不会有问题。
jQuery(document).ready(function(jQuery) {            
            var topMenu = jQuery("#top-menu"),
                offset = 40,
                topMenuHeight = topMenu.outerHeight()+offset,
                // All list items
                menuItems =  topMenu.find('a[href*="#"]'),
                // Anchors corresponding to menu items
                scrollItems = menuItems.map(function(){
                  var href = jQuery(this).attr("href"),
                  id = href.substring(href.indexOf('#')),
                  item = jQuery(id);
                  //console.log(item)
                  if (item.length) { return item; }
                });
            // so we can get a fancy scroll animation
            menuItems.click(function(e){
              var href = jQuery(this).attr("href"),
                id = href.substring(href.indexOf('#'));
                  offsetTop = href === "#" ? 0 : jQuery(id).offset().top-topMenuHeight+1;
              jQuery('html, body').stop().animate({ 
                  scrollTop: offsetTop
              }, 300);
              e.preventDefault();
            });
            // Bind to scroll
            jQuery(window).scroll(function(){
               // Get container scroll position
               var fromTop = jQuery(this).scrollTop()+topMenuHeight;
               // Get id of current scroll item
               var cur = scrollItems.map(function(){
                 if (jQuery(this).offset().top < fromTop)
                   return this;
               });
               // Get the id of the current element
               cur = cur[cur.length-1];
               var id = cur && cur.length ? cur[0].id : "";               
               menuItems.parent().removeClass("active");
               if(id){
                    menuItems.parent().end().filter("[href*='#"+id+"']").parent().addClass("active");
               }
            })
        })
基本上我取代了
menuItems = topMenu.find("a"),
通过
menuItems =  topMenu.find('a[href*="#"]'),
要在某处匹配所有具有锚点的链接,并更改所有必要的设置以使其与此一起工作
menuItems = topMenu.find("a"),为menuItems = topMenu.find("a").slice(0,4),,替换4为[您的页面链接-1]。