如何编辑Accordion可扩展的JavaScript

Question

我只是JavaScript领域的初学者，所以我需要一些专家来指导我如何编辑JavaScript代码，使其一次只展开一行。

（想让它在点击另一行时自动关闭上一行，现在它可以一次扩展所有行）

这是代码https://jsfiddle.net/4L4e88w6/11/

//uses classList, setAttribute, and querySelectorAll
//if you want this to work in IE8/9 youll need to polyfill these
(function() {
  var d = document,
    accordionToggles = d.querySelectorAll('.js-accordionTrigger'),
    setAria,
    setAccordionAria,
    switchAccordion,
    touchSupported = ('ontouchstart' in window),
    pointerSupported = ('pointerdown' in window);

  skipClickDelay = function(e) {
    e.preventDefault();
    e.target.click();
  }

  setAriaAttr = function(el, ariaType, newProperty) {
    el.setAttribute(ariaType, newProperty);
  };
  setAccordionAria = function(el1, el2, expanded) {
    switch (expanded) {
      case "true":
        setAriaAttr(el1, 'aria-expanded', 'true');
        setAriaAttr(el2, 'aria-hidden', 'false');
        break;
      case "false":
        setAriaAttr(el1, 'aria-expanded', 'false');
        setAriaAttr(el2, 'aria-hidden', 'true');
        break;
      default:
        break;
    }
  };
  //function
  switchAccordion = function(e) {
    console.log("triggered");
    e.preventDefault();
    var thisAnswer = e.target.parentNode.nextElementSibling;
    var thisQuestion = e.target;
    if (thisAnswer.classList.contains('is-collapsed')) {
      setAccordionAria(thisQuestion, thisAnswer, 'true');
    } else {
      setAccordionAria(thisQuestion, thisAnswer, 'false');
    }
    thisQuestion.classList.toggle('is-collapsed');
    thisQuestion.classList.toggle('is-expanded');
    thisAnswer.classList.toggle('is-collapsed');
    thisAnswer.classList.toggle('is-expanded');

    thisAnswer.classList.toggle('animateIn');
  };
  for (var i = 0, len = accordionToggles.length; i < len; i++) {
    if (touchSupported) {
      accordionToggles[i].addEventListener('touchstart', skipClickDelay, false);
    }
    if (pointerSupported) {
      accordionToggles[i].addEventListener('pointerdown', skipClickDelay, false);
    }
    accordionToggles[i].addEventListener('click', switchAccordion, false);
  }
})();

* {
  box-sizing: border-box;
}

.heading-primary {
  padding: 3em 0em 0.5em 0em;
  text-align: left;
}

.accordion dl,
.accordion-list {
  border: 1px solid #ddd;
}

.accordion dl:after,
.accordion-list:after {
  content: "";
  display: block;
  height: 0.5em;
  width: 100%;
  background-color: #5c5c5c;
}

.accordion dd,
.accordion__panel {
  background-color: #E3F2FD;
  font-size: 1em;
  line-height: 1.5em;
}

.accordion p {
  padding: 1em 2em 1em 2em;
}

.accordion {
  position: relative;
  background-color: #eee;
}

.accordionTitle,
.accordion__Heading {
  text-align: left;
  font-weight: 500;
  padding: 1em;
  display: block;
  text-decoration: none;
  color: #424242;
  /*  -webkit-transition: background-color 0.2s ease-in-out;
 transition: background-color 0.2s ease-in-out; */
  border-bottom: 1px solid #2a54a2;
}

.accordionTitle:before,
.accordion__Heading:before {
  content: "?";
  font-size: 1.5em;
  font-weight: bold;
  line-height: 0.5em;
  float: right;
  -webkit-transition: -webkit-transform 0.3s ease-in-out;
  transition: -webkit-transform 0.3s ease-in-out;
  transition: transform 0.3s ease-in-out;
  transition: transform 0.3s ease-in-out, -webkit-transform 0.3s ease-in-out;
}

.accordionTitle:hover,
.accordion__Heading:hover {
  background-color: #01579B;
  color: white;
}

.accordionTitleActive,
.accordionTitle.is-expanded {
  background-color: #01579B;
  color: white;
}

.accordionTitleActive:before,
.accordionTitle.is-expanded:before {
  content: "+";
  -webkit-transform: rotate(-225deg);
  -ms-transform: rotate(-225deg);
  transform: rotate(-225deg);
  font-size: 2.5em;
  font-weight: 100;
}

.accordionItem {
  height: auto;
  overflow: hidden;
  max-height: 50em;
  -webkit-transition: max-height 1s;
  transition: max-height 1s;
}

@media screen and (min-width: 48em) {
  .accordionItem {
    /*max-height: 15em;*/
    -webkit-transition: max-height 0.25s;
    transition: max-height 0.25s;
  }
}

.accordionItem.is-collapsed {
  max-height: 0;
}

.no-js .accordionItem.is-collapsed {
  max-height: auto;
}

.animateIn {
  -webkit-animation: accordionIn 0.45s normal ease-in-out both 1;
  animation: accordionIn 0.45s normal ease-in-out both 1;
}

.animateOut {
  -webkit-animation: accordionOut 0.45s alternate ease-in-out both 1;
  animation: accordionOut 0.45s alternate ease-in-out both 1;
}

@-webkit-keyframes accordionIn {
  0% {
    opacity: 0;
    -webkit-transform: translateY(38px);
    transform: translateY(38px);
  }
  100% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
}

@keyframes accordionIn {
  0% {
    opacity: 0;
    -webkit-transform: translateY(38px);
    transform: translateY(38px);
    -webkit-transform-origin: 50% 0;
    transform-origin: 50% 0;
    /*
    -webkit-transform: scale(0.9) rotateX(-60deg);
            transform: scale(0.9) rotateX(-60deg);
    -webkit-transform-origin: 50% 0;
            transform-origin: 50% 0; */
  }
  100% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
}

@-webkit-keyframes accordionOut {
  0% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
  100% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
    transform: scale(0.9) rotateX(-60deg);
  }
}

@keyframes accordionOut {
  0% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
  100% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
    transform: scale(0.9) rotateX(-60deg);
  }
}

<div class="container">
  <h3 class="heading-primary">Q&A</h3>
  <div class="accordion">
    <dl>
      <dt>
                <a href="#accordion1" aria-expanded="false" aria-controls="accordion1" class="accordion-title accordionTitle js-accordionTrigger">First Accordion heading</a>
              </dt>
      <dd class="accordion-content accordionItem is-collapsed" id="accordion1" aria-hidden="true">
        <p>Lorem ipsum dolor sit amet, consectetur <a href="http://www.google.com">Test</a>adipiscing elit. Morbi eu interdum diam. Donec interdum porttitor risus non bibendum. Maecejusto dui, sodales quis luctus a, iaculis eget mauris. </p>
        <p>Aliquam dapibus, ante quis fringilla feugiat, mauris risus condimentum massa, at elementum r. Quisque blandit adipiscing erat vitae dapibus. Nulla aliquam magna nec elementum tincidunt.</p>
        <p>Aliquam dapibus, ante quis fringilla </p>
      </dd>
      <dt>
                <a href="#accordion1" aria-expanded="false" aria-controls="accordion1" class="accordion-title accordionTitle js-accordionTrigger">Second Accordion heading</a>
              </dt>
      <dd class="accordion-content accordionItem is-collapsed" id="accordion1" aria-hidden="true">
        <p>Lorem ipsum dolor sit amet, consectetur <a href="http://www.google.com">Test</a>adipiscing elit. Morbi eu interdum diam. Donec interdum porttitor risus non bibendum. Maecenas sollicitudin eros in quam imperdiet placerat. Cras justo purus, rhoncus
          nec lobortis ut, iaculis vel ipsum. Donec dignissim arcu nec elit faucibus condimentum. Donec facilisis consectetur enim sit amet varius. Pellentesque justo dui, sodales quis luctus a, iaculis eget mauris. </p>
        <p>Aliquam dapibus, ante quis fringilla feugiat, mauris risus condimentum massa, at elementum libero quam ac ligula. Pellentesque at rhoncus dolor. Duis porttitor nibh ut lobortis aliquam. Nullam eu dolor venenatis mauris placerat tristique eget
          id dolor. Quisque blandit adipiscing erat vitae dapibus. Nulla aliquam magna nec elementum tincidunt.</p>
      </dd>
      <dt>
                <a href="#accordion1" aria-expanded="false" aria-controls="accordion1" class="accordion-title accordionTitle js-accordionTrigger">Third Accordion heading</a>
              </dt>
      <dd class="accordion-content accordionItem is-collapsed" id="accordion1" aria-hidden="true">
        <p>Lorem ipsum dolor sit amet, consectetur <a href="http://www.google.com">Test</a>adipiscing elit. Morbi eu interdum diam. Donec interdum porttitor risus non bibendum. Maecenas sollicitudin eros in quam imperdiet placerat. Cras justo purus, rhoncus
          nec lobortis ut, iaculis vel ipsum. Donec dignissim arcu nec elit faucibus condimentum. Donec facilisis consectetur enim sit amet varius. Pellentesque justo dui, sodales quis luctus a, iaculis eget mauris. </p>
        <p>Aliquam dapibus, ante quis fringilla feugiat, mauris risus condimentum massa, at elementum libero quam ac ligula. Pellentesque at rhoncus dolor. Duis porttitor nibh ut lobortis aliquam. Nullam eu dolor venenatis mauris placerat tristique eget
          id dolor. Quisque blandit adipiscing erat vitae dapibus. Nulla aliquam magna nec elementum tincidunt.</p>
      </dd>


    </dl>
  </div>
</div>

Answer 1

我同意@DanielBeck您的代码可以进一步简化，典型的方法是折叠所有项目，然后展开当前点击的项目。

然而，这是另一种方法： 您可以保留对展开元素的引用并在展开新元素之前将其折叠。像这样：

//uses classList, setAttribute, and querySelectorAll
//if you want this to work in IE8/9 youll need to polyfill these
(function() {
  var d = document,
    accordionToggles = d.querySelectorAll('.js-accordionTrigger'),
    setAria,
    setAccordionAria,
    switchAccordion,
    touchSupported = ('ontouchstart' in window),
    pointerSupported = ('pointerdown' in window);

  skipClickDelay = function(e) {
    e.preventDefault();
    e.target.click();
  }

  setAriaAttr = function(el, ariaType, newProperty) {
    el.setAttribute(ariaType, newProperty);
  };
  setAccordionAria = function(el1, el2, expanded) {
    switch (expanded) {
      case "true":
        setAriaAttr(el1, 'aria-expanded', 'true');
        setAriaAttr(el2, 'aria-hidden', 'false');
        break;
      case "false":
        setAriaAttr(el1, 'aria-expanded', 'false');
        setAriaAttr(el2, 'aria-hidden', 'true');
        break;
      default:
        break;
    }
  };
  //function
var expanded;
switchAccordion = function(e) {
    console.log("triggered");
    e.preventDefault();
    var thisAnswer = e.target.parentNode.nextElementSibling;
    var thisQuestion = e.target;
    if(expanded) {
        setAccordionAria(expanded, thisAnswer, 'false');
        expanded.classList.toggle('is-collapsed');
        expanded.classList.toggle('is-expanded');
        var expandedAns = expanded.parentNode.nextElementSibling;
        expandedAns.classList.toggle('is-collapsed');
        expandedAns.classList.toggle('is-expanded');

        expandedAns.classList.toggle('animateIn');
        if(expanded == thisQuestion){
            expanded = undefined;
            return;
        }
    }

    if(thisAnswer.classList.contains('is-collapsed')) {
        setAccordionAria(thisQuestion, thisAnswer, 'true');
        expanded = thisQuestion;
    } else {
        setAccordionAria(thisQuestion, thisAnswer, 'false');
    }
    thisQuestion.classList.toggle('is-collapsed');
    thisQuestion.classList.toggle('is-expanded');
    thisAnswer.classList.toggle('is-collapsed');
    thisAnswer.classList.toggle('is-expanded');

    thisAnswer.classList.toggle('animateIn');
};
  for (var i = 0, len = accordionToggles.length; i < len; i++) {
    if (touchSupported) {
      accordionToggles[i].addEventListener('touchstart', skipClickDelay, false);
    }
    if (pointerSupported) {
      accordionToggles[i].addEventListener('pointerdown', skipClickDelay, false);
    }
    accordionToggles[i].addEventListener('click', switchAccordion, false);
  }
})();

* {
  box-sizing: border-box;
}

.heading-primary {
  padding: 3em 0em 0.5em 0em;
  text-align: left;
}

.accordion dl,
.accordion-list {
  border: 1px solid #ddd;
}

.accordion dl:after,
.accordion-list:after {
  content: "";
  display: block;
  height: 0.5em;
  width: 100%;
  background-color: #5c5c5c;
}

.accordion dd,
.accordion__panel {
  background-color: #E3F2FD;
  font-size: 1em;
  line-height: 1.5em;
}

.accordion p {
  padding: 1em 2em 1em 2em;
}

.accordion {
  position: relative;
  background-color: #eee;
}

.accordionTitle,
.accordion__Heading {
  text-align: left;
  font-weight: 500;
  padding: 1em;
  display: block;
  text-decoration: none;
  color: #424242;
  /*  -webkit-transition: background-color 0.2s ease-in-out;
 transition: background-color 0.2s ease-in-out; */
  border-bottom: 1px solid #2a54a2;
}

.accordionTitle:before,
.accordion__Heading:before {
  content: "?";
  font-size: 1.5em;
  font-weight: bold;
  line-height: 0.5em;
  float: right;
  -webkit-transition: -webkit-transform 0.3s ease-in-out;
  transition: -webkit-transform 0.3s ease-in-out;
  transition: transform 0.3s ease-in-out;
  transition: transform 0.3s ease-in-out, -webkit-transform 0.3s ease-in-out;
}

.accordionTitle:hover,
.accordion__Heading:hover {
  background-color: #01579B;
  color: white;
}

.accordionTitleActive,
.accordionTitle.is-expanded {
  background-color: #01579B;
  color: white;
}

.accordionTitleActive:before,
.accordionTitle.is-expanded:before {
  content: "+";
  -webkit-transform: rotate(-225deg);
  -ms-transform: rotate(-225deg);
  transform: rotate(-225deg);
  font-size: 2.5em;
  font-weight: 100;
}

.accordionItem {
  height: auto;
  overflow: hidden;
  max-height: 50em;
  -webkit-transition: max-height 1s;
  transition: max-height 1s;
}

@media screen and (min-width: 48em) {
  .accordionItem {
    /*max-height: 15em;*/
    -webkit-transition: max-height 0.25s;
    transition: max-height 0.25s;
  }
}

.accordionItem.is-collapsed {
  max-height: 0;
}

.no-js .accordionItem.is-collapsed {
  max-height: auto;
}

.animateIn {
  -webkit-animation: accordionIn 0.45s normal ease-in-out both 1;
  animation: accordionIn 0.45s normal ease-in-out both 1;
}

.animateOut {
  -webkit-animation: accordionOut 0.45s alternate ease-in-out both 1;
  animation: accordionOut 0.45s alternate ease-in-out both 1;
}

@-webkit-keyframes accordionIn {
  0% {
    opacity: 0;
    -webkit-transform: translateY(38px);
    transform: translateY(38px);
  }
  100% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
}

@keyframes accordionIn {
  0% {
    opacity: 0;
    -webkit-transform: translateY(38px);
    transform: translateY(38px);
    -webkit-transform-origin: 50% 0;
    transform-origin: 50% 0;
    /*
    -webkit-transform: scale(0.9) rotateX(-60deg);
            transform: scale(0.9) rotateX(-60deg);
    -webkit-transform-origin: 50% 0;
            transform-origin: 50% 0; */
  }
  100% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
}

@-webkit-keyframes accordionOut {
  0% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
  100% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
    transform: scale(0.9) rotateX(-60deg);
  }
}

@keyframes accordionOut {
  0% {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
  100% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
    transform: scale(0.9) rotateX(-60deg);
  }
}

<div class="container">
  <h3 class="heading-primary">Q&A</h3>
  <div class="accordion">
    <dl>
      <dt>
                <a href="#accordion1" aria-expanded="false" aria-controls="accordion1" class="accordion-title accordionTitle js-accordionTrigger">First Accordion heading</a>
              </dt>
      <dd class="accordion-content accordionItem is-collapsed" id="accordion1" aria-hidden="true">
        <p>Lorem ipsum dolor sit amet, consectetur <a href="http://www.google.com">Test</a>adipiscing elit. Morbi eu interdum diam. Donec interdum porttitor risus non bibendum. Maecejusto dui, sodales quis luctus a, iaculis eget mauris. </p>
        <p>Aliquam dapibus, ante quis fringilla feugiat, mauris risus condimentum massa, at elementum r. Quisque blandit adipiscing erat vitae dapibus. Nulla aliquam magna nec elementum tincidunt.</p>
        <p>Aliquam dapibus, ante quis fringilla </p>
      </dd>
      <dt>
                <a href="#accordion1" aria-expanded="false" aria-controls="accordion1" class="accordion-title accordionTitle js-accordionTrigger">Second Accordion heading</a>
              </dt>
      <dd class="accordion-content accordionItem is-collapsed" id="accordion1" aria-hidden="true">
        <p>Lorem ipsum dolor sit amet, consectetur <a href="http://www.google.com">Test</a>adipiscing elit. Morbi eu interdum diam. Donec interdum porttitor risus non bibendum. Maecenas sollicitudin eros in quam imperdiet placerat. Cras justo purus, rhoncus
          nec lobortis ut, iaculis vel ipsum. Donec dignissim arcu nec elit faucibus condimentum. Donec facilisis consectetur enim sit amet varius. Pellentesque justo dui, sodales quis luctus a, iaculis eget mauris. </p>
        <p>Aliquam dapibus, ante quis fringilla feugiat, mauris risus condimentum massa, at elementum libero quam ac ligula. Pellentesque at rhoncus dolor. Duis porttitor nibh ut lobortis aliquam. Nullam eu dolor venenatis mauris placerat tristique eget
          id dolor. Quisque blandit adipiscing erat vitae dapibus. Nulla aliquam magna nec elementum tincidunt.</p>
      </dd>
      <dt>
                <a href="#accordion1" aria-expanded="false" aria-controls="accordion1" class="accordion-title accordionTitle js-accordionTrigger">Third Accordion heading</a>
              </dt>
      <dd class="accordion-content accordionItem is-collapsed" id="accordion1" aria-hidden="true">
        <p>Lorem ipsum dolor sit amet, consectetur <a href="http://www.google.com">Test</a>adipiscing elit. Morbi eu interdum diam. Donec interdum porttitor risus non bibendum. Maecenas sollicitudin eros in quam imperdiet placerat. Cras justo purus, rhoncus
          nec lobortis ut, iaculis vel ipsum. Donec dignissim arcu nec elit faucibus condimentum. Donec facilisis consectetur enim sit amet varius. Pellentesque justo dui, sodales quis luctus a, iaculis eget mauris. </p>
        <p>Aliquam dapibus, ante quis fringilla feugiat, mauris risus condimentum massa, at elementum libero quam ac ligula. Pellentesque at rhoncus dolor. Duis porttitor nibh ut lobortis aliquam. Nullam eu dolor venenatis mauris placerat tristique eget
          id dolor. Quisque blandit adipiscing erat vitae dapibus. Nulla aliquam magna nec elementum tincidunt.</p>
      </dd>


    </dl>
  </div>
</div>