Waypoint unrecognized on Ajax-loaded content

I'm loading a page into a div. I'm also attempting to establish a waypoint, so that when the user scrolls down the page, the menu will change colors.

The problem I am having is the new height of the div is not recognized by the browser once the ajax content is loaded.

Here's what I have:

$(".cta").live('click', function () {
    $('#faq').load('about-us/faqs/index.html'),
    function () {
        $("#faq").waypoint(function (event, direction) {
            if (direction === 'up') {
                $("#siteNav li a").removeClass("siteNavSelected");
                $("#siteNav li.nav3 a").addClass("siteNavSelected");
            }
        }, {
            offset: function () {
                return $.waypoi开发者_如何学Cnts('viewportHeight') - $("#faq").outerHeight();
            }

        });
    }
    return false;
});

Any ideas? Thanks.

Use $.waypoints('refresh');, from the documentation:

This will force a recalculation of each waypoint’s trigger point based on its offset option. This is called automatically whenever the window is resized or new waypoints are added. If your project is changing the DOM or page layout without doing one of these things, you may want to manually call it.

I'm not familiar with the intrinsics of the waypoint plugin, but you could also bind a scroll event and then capture the .scrollTop() value. Would look something like this:

$(document).bind('scroll', function(event) {        
    var scrollTop = $(window).scrollTop();
    if (scrollTop < 1000 && $('siteNav li').hasClass('styleA')) { return; }
    else { 
        $('siteNav li').removeClass('styleB');
        $('siteNav li').addClass('styleA');
    }
    if (scrollTop > 1000 && $('siteNav li').hasClass('styleB')) { return; }
    else {
        $('siteNav li').removeClass('styleA');
        $('siteNav li').addClass('styleB');
    }
});

You have to play with the values a little to get it acting at the right spot. Also you have to use a greater or less than value in the test as if a user is at the top of the page and uses the scroll-wheel on his mouse to fly down the page, you don't get every value in between.