Show/hide elements when other elements change class - jQuery

Question

I have a content wrapper which has several sections in it, each section with a different id. The sections can be accessed with a menu navigation which triggers a transform operation who uses translate3d to go between the sections, on horizontal, using an class named active to show which section should be displayed. I placed two anchors with absolute position towards the content wrapper, something like arrows in a slideshow one on the left and one on the right.

Here is how the code looks

    <div id="wrapper">
        <a class="left-arrow" href="#"></a>
        <a class="right-arrow" href="#"></a>

        <header>
            <nav id="main">
                <a class="active" href="#!/one">one</a>
                <a href="#!/two">two</a>
                <a href="#!/three">three</a>
                <a href="#!/four">four</a>
            </nav>
        </header>
        <div class="content_wrapper" style="display: block; transform: translate3d(0px, 0px, 0px);">
            <section id="one" class="active">content one</section>
            <section id="two">content two</section>
            <section id="three">content three</section>
            <section id="four">content four</section>
        </div>
    </div>

the CSS

    .left-arrow{ background: url('../img/left-arrow.png') left top no-repeat; height: 64px; width: 16px; display: block; position: absolute; top: 180px; left: 0; z-index: 10;}
    .right-arrow{ background: url('../img/right-arrow.png') right top no-repeat; height: 64px; width: 16px; display: block; position: absolute; top: 180px; right: 0; z-index: 10;}

My problem is that I don't know how to hide the left arrow when the first section has the class active , and the right arrow when the last section has the class active . I tried with on and change but obviously I failed, I'm a rookie to jQuery element and event manipulation. Which selector should I use and which event? Can someone please give me some directions?

here is the jQuery part

    (function (e) {

        var r = !1;
        e(window).on("hashchange", function (i) {
            var s = e("section#" + document.location.hash.replace("#!/", ""));
            if (!r && !s.hasClass("active")) {
                r = !0;
                e('nav#main a[href="' + document.location.hash + '"]').addClass("active").siblings().removeClass("active");
                e("section.active").animate({
                    scrollTop: 0
                }, 300);
                e("section.active").children("footer").children("div.box").hide();
                s.addClass("active").siblings().removeClass("active");
                if (Modernizr.csstransitions && Modernizr.csstransforms3d) e("div.content_wrapper").transition({
                    transform: "translate3d(-" + 1e3 * s.index() + "px, 0, 0)"
                }, {
                    duration: 800,
                    easing: "cubic-bezier(0.770, 0.000, 0.175, 1.000)"
                }, function () {
                    r = !1
                });
                else {
                    e("div.content_wrapper").animate({
                        left: "-" + 1e3 * s.index() + "px"
                    }, {
                        duration: 800,
                        queue: !0
                    });
                    r = !1
                }
            }
        });

    })

Answer 1

Would add a class to all the sections so you can add or remove and not have to focus on specific ID being first/last

<section id="one" class="content active">content one</section>

function setArrowState(){
    var $content=$('.content');
    $('.left-arrow')[ $content.first().is('.active') ? 'hide' :'show' ]();
     $('.right-arrow')[ $content.last().is('.active') ? 'hide' :'show' ]();
}

$(function(){
    /* set arrows on page load*/
    setArrowState();
});

EDIT: In haschange code shown, call setArrowState() on line after .addClass("active").siblings().removeClass("active");

Answer 2

You just need to have a variable know which is the element selected, so you can remove the class, and then set on the click event to add the class.

var menu1 = document.querySelector('#main1');
var menu2 = document.querySelector('#main2');
    // etc

var selected = menu1;

var activeClass = function()
    {
    $(selected).removeClass('active');

    $(this).addClass('active');

    selected = this;
    };


menu1.onclick = activeClass;
menu2.onclick = activeClass;