Currently i am building a storytelling website, where the client can iterate through several videos. However, there is also a page with chapters on the website. So when the client clicks on the next or previous button, the chapters should be lighten up on the chapter he currently is on.
At the moment i build a click counter, so the counter is counting up, when he clicked on next and counting down, when clicked on previous. I have 11 chapters, so 11 video’s. I am checking the chapters by index. They are going from 0 to 11. When the client hits the next button, he’s going to the next video and the click counter goes up with one.
At the moment i have trouble to connect this click counter to the current index of the chapter. So if the click counter goes to two for instance, the background of only chapter 2 (index 2) should be lighten up.
At the moment i have this:
<a href="#" class="vorige prev-rew button-sound">
<svg>icon</svg>
</a>
<a href="#" class="next prev-rew button-sound">
<svg> icon</svg>
</a>
<div class="marketing-chapter job-chapter">
<a href="#">
<div class="anchor-point chapter-1">
<p>1</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-2">
<p>2</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-3">
<p>3</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-4">
<p>4</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-5">
<p>5</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-6">
<p>6</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-7">
<p>7</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-8">
<p>8</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-9">
<p>9</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-10">
<p>10</p>
</div>
</a>
<a href="#">
<div class="anchor-point chapter-11">
<p>11</p>
</div>
</a>
</div>
// Anchorpoint loop
var set = $(".anchor-point");
var length = set.length;
var ViewportCount = 1;
$('.prev-rew').on("click", function() {
if ($(this).hasClass('next')) {
console.log('klikkert next');
ViewportCount = ViewportCount + 1;
} else if ($(this).hasClass('vorige')) {
console.log('klikkert vorige');
ViewportCount = ViewportCount - 1;
}
set.each(function(index) {
index = ViewportCount;
console.log(index);
console.log(ViewportCount);
if(index == ViewportCount){
// Change the background-color of the number, connected to the index. So
current chapter will light up
}
});
});
>Solution :
To do what you require you can use the eq() method to directly select the element in the collection without a loop:
var set = $(".anchor-point");
var ViewportCount = 0;
$('.prev-rew').on("click", function() {
if ($(this).hasClass('next')) {
ViewportCount = ViewportCount + 1;
} else if ($(this).hasClass('vorige')) {
ViewportCount = ViewportCount - 1;
}
set.removeClass('active').eq(ViewportCount % set.length).addClass('active');
});.active { background-color: #C00; }<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<a href="#" class="vorige prev-rew button-sound">Previous</a>
<a href="#" class="next prev-rew button-sound">Next</a>
<div class="marketing-chapter job-chapter">
<a href="#">
<div class="anchor-point chapter-1 active"><p>1</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-2"><p>2</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-3"><p>3</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-4"><p>4</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-5"><p>5</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-6"><p>6</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-7"><p>7</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-8"><p>8</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-9"><p>9</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-10"><p>10</p></div>
</a>
<a href="#">
<div class="anchor-point chapter-11"><p>11</p></div>
</a>
</div>However, you can avoid the need for the counter variable and instead move the active class based on its current position in the DOM. The <a> elements wrapping the div can also be removed as it’s invalid HTML, it makes the JS more straightforward and it’s also not necessary in this case
$('.prev-rew').on("click", function() {
let $current = $('.active');
let $target = $current[$(this).data('action')]();
if ($target.length) {
$current.removeClass('active');
$target.addClass('active');
}
});.active {
background-color: #C00;
}<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<a href="#" class="vorige prev-rew button-sound" data-action="prev">Previous</a>
<a href="#" class="next prev-rew button-sound" data-action="next">Next</a>
<div class="marketing-chapter job-chapter">
<div class="anchor-point chapter-1 active"><p>1</p></div>
<div class="anchor-point chapter-2"><p>2</p></div>
<div class="anchor-point chapter-3"><p>3</p></div>
<div class="anchor-point chapter-4"><p>4</p></div>
<div class="anchor-point chapter-5"><p>5</p></div>
<div class="anchor-point chapter-6"><p>6</p></div>
<div class="anchor-point chapter-7"><p>7</p></div>
<div class="anchor-point chapter-8"><p>8</p></div>
<div class="anchor-point chapter-9"><p>9</p></div>
<div class="anchor-point chapter-10"><p>10</p></div>
<div class="anchor-point chapter-11"><p>11</p></div>
</div>