Javascript Slider doesn't work correctly with transition end

Question

I don't know why people's are not answering this question.I'm making a horizontal infinite loop slider. What approach i'm using is making a ul container which has 3 images, for example if there are 3 images then clone the first image and place it to the end of the slider, same with last image make clone and place it before the first image. So now total images are 5. Default slider translation always start from first image not from clone one. Here is an example. What i'm facing is, I want to reset the slider after slider comes to the last clone image with same continuous loop like a carousel slider. I try using addEventListener with the event name transitionend but that event doesn't perform correctly and showing unsatisfied behavior. Is there a way to fix this?

(function () {
    var resetTranslation = "translate3d(-300px,0px,0px)";
    var elm = document.querySelector('.Working');
    elm.style.transform = resetTranslation;
    var arr = document.querySelectorAll('.Working li');
    var clonefirst,
        clonelast,
        width = 300;
    index = 2;
    clonefirst = arr[0].cloneNode(true);
    clonelast = arr[arr.length - 1].cloneNode(true);

    elm.insertBefore(clonelast, arr[0]);
    arr[arr.length - 1].parentNode.insertBefore(clonefirst, arr[arr.length - 1].nextSibling);
    //Update
    arr = document.querySelectorAll('.Working li');
    elm.style.transition = 'transform 1.5s ease';

    setInterval(function () {

        elm.style.transform = 'translate3d(-' + index * width + 'px,0px,0px)';
        if (index == arr.length - 1) {
            elm.addEventListener('transitionend', function () {
                elm.style.transform = resetTranslation;
            });
            index = 1;
        }
        index++;

    }, 4000)

})();

*{
    box-sizing: border-box;
}
.wrapper{
    position: relative;
    overflow: hidden;
    height: 320px;
    width: 300px;


}

.Working{
    list-style: none;
    margin: 0;
    padding: 0;
    position: relative;
    width: 3125%;


}
.Working li{
    position: relative;
    float: left;
}


img{
    max-width: 100%;
    display: block;
}

.SubContainer:after{
    display: table;
    clear: both;
    content: "";
}

<div class="wrapper">
    <ul class="SubContainer Working">
        <li> <img class="" src="http://i.imgur.com/HqQb9V9.jpg" /></li>
        <li><img class="" src="http://i.imgur.com/PMBBc07.jpg" /></li>
        <li><img  class="" src="http://i.imgur.com/GRrGSxe.jpg" /></li>
    </ul>
</div>

Answer 1

I've messed around with your code to hack in a fix: https://jsfiddle.net/rap8o3q0/

The changed part:

var currentItem = 1;

setInterval(function () {
    var getWidth = window.innerWidth;

    if(len === currentItem){
        i = 1;
        currentItem = 1;
    } else {
        currentItem++;
        i++;
    }

    var val = 'translate3d(-' + (i-1) * getWidth + 'px,0px,0px)';
    UnorderedListElement.style.transform = val;

}, 3000);

Answer 2

Your transition end event is not immediately fire because last transition doesn't computed when last clone image appear. You can easily achieve this thing by using setTimeout function and pass number of milliseconds to wait, after that reset the translation. I don't know it's an efficient solution but i think its easily done by using this function. Now I'm fixing your code with this.

(function () {
    var elm = document.querySelector('.Working');
    var arr = document.querySelectorAll('.Working li');
    var clonefirst,
        clonelast,
        width = 300;
    index = 2;
    clonefirst = arr[0].cloneNode(true);
    clonelast = arr[arr.length - 1].cloneNode(true);

    elm.insertBefore(clonelast, arr[0]);
    arr[arr.length - 1].parentNode.insertBefore(clonefirst, arr[arr.length - 1].nextSibling);
    //Update
    arr = document.querySelectorAll('.Working li');

     setInterval(function () {
        $(elm).css({
            'transform': 'translate3d(-' + (index * width) + 'px,0px,0px)',
            'transition': 'transform 1.5s ease'
        });
        if (index == arr.length - 1) {
            setTimeout(function () {
                $(elm).css({'transform': 'translate3d(-300px,0px,0px)', 'transition': 'none'});
                index = 1;
            }, 1400);

        }
        index++;

    }, 2000)

})();

* {
    box-sizing: border-box;
}

.wrapper {
    position: relative;
    overflow: hidden;
    height: 320px;
    width: 300px;
    margin-top: 8px;

}

.Working {
    list-style: none;
    margin: 0;
    padding: 0;
    position: relative;
    transform: translateX(-300px);
    width: 3125%;

}

.Working li {
    position: relative;
    float: left;
}

img {
    max-width: 100%;
    display: block;
}

.SubContainer:after {
    display: table;
    clear: both;
    content: "";
}

#checkboxer:checked + .wrapper {
    overflow: visible;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<label for="checkboxer">Remove Overflow Hidden</label>
<input type="checkbox" id="checkboxer" name="checkboxer"/>

<div class="wrapper">
    <ul class="SubContainer Working">
        <li> <img class="" src="http://i.imgur.com/HqQb9V9.jpg" /></li>
        <li><img class="" src="http://i.imgur.com/PMBBc07.jpg" /></li>
        <li><img  class="" src="http://i.imgur.com/GRrGSxe.jpg" /></li>
    </ul>
</div>