Кнопка следующего слайда

Question

У меня проблемы с размещением кнопки на следующем слайде, мышь и клавиши на любой клавиатуре работают, но я хотел поставить кнопку или 2, одну на go назад и другую, чтобы двигаться дальше, я подумал о таймер, но вероятность успеха была 0%, я стараюсь, но это очень сложно, если кто-нибудь может мне в этом помочь, мне очень поможет

/*********************
 *	Helpers Code
 ********************/
/**
 *  @function   DOMReady
 *
 *  @param callback
 *  @param element
 *  @param listener
 *  @returns {*}
 *  @constructor
 */
const DOMReady = ((
  callback  = () => {},
  element   = document,
  listener  = 'addEventListener'
) => {
  return (element[listener]) ? element[listener]('DOMContentLoaded', callback) : window.attachEvent('onload', callback);
});

/**
 *  @function   ProjectAPI
 *
 *  @type {{hasClass, addClass, removeClass}}
 */
const ProjectAPI = (() => {
  let hasClass,
      addClass,
      removeClass;

  hasClass = ((el, className) => {
    if (el === null) {
      return;
    }

    if (el.classList) {
      return el.classList.contains(className);
    }
    else {
      return !!el.className.match(new RegExp('(\\s|^)' + className + '(\\s|$)'));
    }
  });

  addClass = ((el, className) => {
    if (el === null) {
      return;
    }

    if (el.classList) {
      el.classList.add(className);
    }
    else if (!hasClass(el, className)) {
      el.className += ' ' + className
    }
  });

  removeClass = ((el, className) => {
    if (el === null) {
      return;
    }

    if (el.classList) {
      el.classList.remove(className);
    }
    else if (hasClass(el, className)) {
      let reg = new RegExp('(\\s|^)' + className + '(\\s|$)');

      el.className = el.className.replace(reg, ' ');
    }
  });

  return {
    hasClass:     hasClass,
    addClass:     addClass,
    removeClass:  removeClass
  };
})();


/*********************
 *	Application Code
 ********************/
/**
 *  @function   readyFunction
 *
 *  @type {Function}
 */
const readyFunction = (() => {

  const KEY_UP    = 38;
  const KEY_DOWN  = 40;

  let scrollingClass          = 'js-scrolling',
      scrollingActiveClass    = scrollingClass + '--active',
      scrollingInactiveClass  = scrollingClass + '--inactive',

      scrollingTime           = 1350,
      scrollingIsActive       = false,

      currentPage             = 1,
      countOfPages            = document.querySelectorAll('.' + scrollingClass + '__page').length,

      prefixPage              = '.' + scrollingClass + '__page-',

      _switchPages,
      _scrollingUp,
      _scrollingDown,

      _mouseWheelEvent,
      _keyDownEvent,

      init;

  /**
   *  @function _switchPages
   *
   *  @private
   */
  _switchPages = () => {

    let _getPageDomEl;

	  /**
     *  @function _getPageDomEl
     *
     *  @param page
     *  @returns {Element}
     *  @private
	   */
    _getPageDomEl      = (page = currentPage) => {
      return document.querySelector(prefixPage + page);
    };

    scrollingIsActive  = true;


    ProjectAPI.removeClass(
      _getPageDomEl(),
      scrollingInactiveClass
    );
    ProjectAPI.addClass(
      _getPageDomEl(),
      scrollingActiveClass
    );

    ProjectAPI.addClass(
      _getPageDomEl(currentPage - 1),
      scrollingInactiveClass
    );

    ProjectAPI.removeClass(
      _getPageDomEl(currentPage + 1),
      scrollingActiveClass
    );


    setTimeout(
      () => {
        return scrollingIsActive = false;
      },
      scrollingTime
    );
  };
	/**
   *  @function _scrollingUp
   *
   *  @private
   */
  _scrollingUp = () => {
    if (currentPage === 1) {
      return;
    }

    currentPage--;

    _switchPages();
  };
	/**
   *  @function _scrollingDown
   *
   *  @private
   */
  _scrollingDown = () => {
    if (currentPage === countOfPages) {
      return;
    }

    currentPage++;

    _switchPages();
  };
	/**
   *  @function _mouseWheelEvent
   *
   *  @param e
   *  @private
   */
  _mouseWheelEvent = (e) => {
    if (scrollingIsActive) {
      return;
    }

    if (e.wheelDelta > 0 || e.detail < 0) {
      _scrollingUp();
    }
    else if (e.wheelDelta < 0 || e.detail > 0) {
      _scrollingDown();
    }
  };
	/**
   *  @function _keyDownEvent
   *
   *  @param e
   *  @private
   */
  _keyDownEvent = (e) => {
    if (scrollingIsActive) {
      return;
    }

    let keyCode = e.keyCode || e.which;

    if (keyCode === KEY_UP) {
      _scrollingUp();
    }
    else if (keyCode === KEY_DOWN) {
      _scrollingDown();
    }
  };

  /**
   *  @function init
   *
   *  @note     auto-launch
   */
  init = (() => {
    document.addEventListener(
      'mousewheel',
      _mouseWheelEvent,
      false
    );
    document.addEventListener(
      'DOMMouseScroll',
      _mouseWheelEvent,
      false
    );

    document.addEventListener(
      'keydown',
      _keyDownEvent,
      false
    );
  })();

});


/**
 *  Launcher
 */
DOMReady(readyFunction);

/***********************
 *  Variables
 **********************/
/***********************
 *  Project Main Styles
 **********************/
*,
*:before,
*:after {
  box-sizing: border-box;
  margin: 0;
  padding: 0; }

body {
  font-family: "Open Sans", sans-serif;
  background-color: #282828; }

.slider-pages {
  overflow: hidden;
  position: relative;
    zoom: 59%;
width: 94%;
    left: 3%;
  height: 100vh; }

.slider-page {
  position: absolute;
  top: 0;
  width: 50%;
  height: 100vh;
  transition: transform 1350ms; }

.slider-page--skew {
  overflow: hidden;
  position: absolute;
  top: 0;
  width: 140%;
  height: 100%;
  background: #282828;
  transform: skewX(-18deg); }

.slider-page--left {
  left: 0;
  transform: translateX(-32.5vh) translateY(100%) translateZ(0); }
  .slider-page--left .slider-page--skew {
    left: -40%; }
  .slider-page--left .slider-page__content {
    padding: auto 30% auto 30%;
    transform-origin: 100% 0; }

.slider-page--right {
  left: 50%;
  transform: translateX(32.5vh) translateY(-100%) translateZ(0); }
  .slider-page--right .slider-page--skew {
    right: -40%; }
  .slider-page--right .slider-page__content {
    padding: auto 30% auto 30%;
    transform-origin: 0 100%; }

.slider-page__content {
  position: absolute;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-flow: column wrap;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  padding: 0 30% 0 30%;
  color: #e2e2e2;
  background-size: cover;
  transform: skewX(18deg);
  transition: transform 1350ms; }

.slider-page__title {
  margin-bottom: 1em;
  font-size: 1em;
  text-align: center;
  text-transform: uppercase; }

.slider-page__title--big {
  font-size: 1.2em; }

.slider-page__description {
  font-size: 1em;
  text-align: center; }

.slider-page__link {
  color: #80a1c1; }
  .slider-page__link:hover, .slider-page__link:focus {
    color: #6386a9;
    text-decoration: none; }

/***********************
 *  Project JS Styles
 **********************/
.js-scrolling__page {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%; }

.js-scrolling--active .slider-page {
  transform: translateX(0) translateY(0) translateZ(0); }

.js-scrolling--inactive .slider-page__content {
  transform: skewX(18deg) scale(0.9); }

.js-scrolling__page-1 .slider-page--left .slider-page__content {
  background-image: url("https://cdn.discordapp.com/attachments/584536200052867077/687769359183380537/ram-of-re-zero-starting-life-in-another-world-wallpaper-3440x1440-2148_15.png"); }
.js-scrolling__page-1 .slider-page--right .slider-page__content {
  background-color: #282828; }

.js-scrolling__page-2 .slider-page--left .slider-page__content {
  background-color: #e2e2e2; }
.js-scrolling__page-2 .slider-page--left .slider-page__title,
.js-scrolling__page-2 .slider-page--left .slider-page__description {
  color: #282828; }
.js-scrolling__page-2 .slider-page--right .slider-page__content {
  background-image: url("https://cdn.discordapp.com/attachments/584536200052867077/687766774950789160/9ibz1cnnwdp31.png"); }

.js-scrolling__page-3 .slider-page--left .slider-page__content {
  background-image: url("https://cdn.discordapp.com/attachments/584536200052867077/687773688782913563/9ibz1cnnwdp31.png"); }
.js-scrolling__page-3 .slider-page--right .slider-page__content {
  background-color: #282828; }

<section class="slider-pages">

  <article class="js-scrolling__page js-scrolling__page-1 js-scrolling--active">
    <div class="slider-page slider-page--left">
      <div class="slider-page--skew">
        <div class="slider-page__content">
        </div>
        <!-- /.slider-page__content -->
      </div>
      <!-- /.slider-page--skew -->
    </div>
    <!-- /.slider-page slider-page--left -->

    <div class="slider-page slider-page--right">
      <div class="slider-page--skew">
        <div class="slider-page__content">
          <h1 class="slider-page__title slider-page__title--big">
            Re:Zero kara Hajimeru Isekai Seikatsu
          </h1>
          <!-- /.slider-page__title slider-page__title--big -->
          <h2 class="slider-page__title">
            
          </h2>
          <!-- /.slider-page__title -->
          <p class="slider-page__description">
          End
          </p>
          <!-- /.slider-page__description -->
        </div>
        <!-- /.slider-page__content -->
      </div>
      <!-- /.slider-page--skew -->
    </div>
    <!-- /.slider-page slider-page--right -->
  </article>
  <!-- /.js-scrolling__page js-scrolling__page-1 js-scrolling--active -->


  <article class="js-scrolling__page js-scrolling__page-2">
    <div class="slider-page slider-page--left">
      <div class="slider-page--skew">
        <div class="slider-page__content">
          <h1 class="slider-page__title">
            EVANGELION 3.0 + 1.0
          </h1>
          <!-- /.slider-page__title -->
          <p class="slider-page__description">
            ENd
          </p>
          <!-- /.slider-page__description -->
        </div>
        <!-- /.slider-page__content -->
      </div>
      <!-- /.slider-page--skew -->
    </div>
    <!-- /.slider-page slider-page--left -->

    <div class="slider-page slider-page--right">
      <div class="slider-page--skew">
        <div class="slider-page__content">
        </div>
        <!-- /.slider-page__content -->
      </div>
      <!-- /.slider-page--skew -->
    </div>
    <!-- /.slider-page slider-page--right -->
  </article>
  <!-- /.js-scrolling__page js-scrolling__page-2 -->


  

Answer 1

Вы можете использовать функции, которые вы уже определили, а именно _scrollingUp и _scrollingDown, и назначить их для событий кнопок onclick. При этом эти функции будут вызываться при каждом нажатии правой кнопки.

Упрощенный пример будет:

document.getElementById("prev").onclick = _scrollingUp;
document.getElementById("next").onclick = _scrollingDown;

<button id="prev">Previous</button>
<button id="next">Next</button>