jQuery导航点具有平滑滚动

Question

I am having a little trouble with JQuery waypoints here. Im using it for my auto scroll navigation on my one page site:

signaturestories.eu

It works fine when i use my scroll wheel. I need it to change the color of my nav items whenever a certain element reaches top of the screen. The problem is when you press sign up --> about --> sign up, then is doesnt change the color that third time.

script.js:

    $('a[href^="#"]').bind('click.smoothscroll',function (e) {
        e.preventDefault();

        var target = this.hash,
        $target = $(target);

        $('html, body').stop().animate({
            'scrollTop': $target.offset().top-40
        }, 900, 'swing', function () {
            window.location.hash = target;
        });
    });


var currentMenuObject = '';

$('#wrapper').waypoint(function() {
    $(currentMenuObject).css('color', '#f2e0bd');
    currentMenuObject = '#top';
    $(currentMenuObject).css('color', 'black');
}, { offset: '55'});

$('#introarticle').waypoint(function() {
    $(currentMenuObject).css('color', '#f2e0bd');
    currentMenuObject = '#top';
    $(currentMenuObject).css('color', 'black');
}, { offset: '55'});

$('#signsection').waypoint(function() {
    $(currentMenuObject).css('color', '#f2e0bd');
    currentMenuObject = '#signup';
    $(currentMenuObject).css('color', 'black');
}, { offset: '55'});

$('#storyarticle').waypoint(function() {
    $(currentMenuObject).css('color', '#f2e0bd');
    currentMenuObject = '#about';
    $(currentMenuObject).css('color', 'black');
}, { offset: '55'});

Answer 1

You are calling this bit before adding jquery to page:

$(document).ready(function(){
    //jQuery code goes here and will be executed as soon as the page has finished loading
});    

This throws an $ is not a function error and stops executing code.