when i scroll the page, i want to add class active menu item. i can get the current div id like this var currSection = $(this).attr(‘id’). im stuck with id and data-id matching. here is the codes. ty for helping guys.
$(document).scroll(function() {
    var cutoff = $(window).scrollTop();
    $('div').each(function(){
        if($(this).offset().top + $(this).height() > cutoff){
            $('div').removeClass('current');
            $(this).addClass('current');
            var currSection = $(this).attr('id'); 
            console.log(currSection);
            if ($('.circle li').data('id') == currSection) {
              
            };
            return false; 
        }
    });
});ul{
  position:fixed;
  z-index:9;
  top:0;
}
.active{
  color:red;
}
div{
  height:500px;
}
div:nth-child(odd){
  background:green;
}
div:nth-child(even){
  background:blue;
}<div id="home"></div>
<div id="who"></div>
<div id="team"></div>
<div id="why"></div>
<div id="contact"></div>
<ul class="circle">
    <li data-id="home" class="active">a</li>
    <li data-id="who">b</li>
    <li data-id="team">c</li>
    <li data-id="why">d</li>
    <li data-id="contact">f</li>
</ul>Advertisement
Answer
Change scroll event listener to this
$(document).scroll(function () {
    var cutoff = $(window).scrollTop();
    $('div').each(function () {
        if ($(this).offset().top + $(this).height() > cutoff) {
            $('div').removeClass('current');
            $(this).addClass('current');
            var currSection = $(this).attr('id');
            console.log(currSection);
            $('li').removeClass('active');
            $('li[data-id=' + currSection + ']').addClass('active');
            return false;
        }
    });
});