javascript - 切换显示/隐藏 DIV 错误

Question

我有以下代码，它采用一些简单的 HTML 并使用一些 JS 来显示/隐藏它。

// So forEach can be used on 'querySelectorAll' and 'getElementsByClassName' collections
HTMLCollection.prototype.forEach = NodeList.prototype.forEach = Array.prototype.forEach;

function HideShow(e, itm_id) {
  var tbl = document.getElementById(itm_id);
  if (tbl.style.display == "") {
    e.innerHTML = "<i class='fa fa-plus' aria-hidden='true'></i>";
    tbl.style.display = "none";
  } else {
    e.innerHTML = "<i class='fa fa-minus' aria-hidden='true'></i>";
    tbl.style.display = "";
  }
}


// -----------------------------------------------------------
// NEW Code


// New toggle links
let toggles = document.getElementsByClassName('toggler');

// Attach click event
toggles.forEach(link => link.addEventListener('click', fnToggleElement))

// Event handler definition
function fnToggleElement() {
  let elements = document.querySelectorAll(`[id^="${this.dataset.selector}"]`)
  let className = 'd-none'
  elements.forEach(el => {
    let fas = el.parentElement.closest('.item,.sub-container,.menu-container').querySelectorAll('.fa')
    if (el.classList.contains(className)) {
      el.classList.remove(className)
      fas.forEach(fa => {
        fa.classList.remove('fa-plus')
        fa.classList.add('fa-minus')
      })
    } else {
      el.classList.add(className)
      fas.forEach(fa => {
        fa.classList.remove('fa-minus')
        fa.classList.add('fa-plus')
      })
    }
  })
}

body {
  background: #fff;
  margin-top: 20px;
}

h1.heading {
  font: 'Oswald';
  text-transform: uppercase;
}

td {
  background: #f1f1f1;
  border-bottom: 1px solid #ccc;
  border-right: 1px solid #ccc;
  padding: 20px;
  margin: 5px;
  border-top: 1px solid #fff;
  border-left: 1px solid #fff;
}

.wrappingmapping {
  margin: 20px 0 0 20px;
  border-radius: 85px;
  overflow: hidden;
  border: 10px solid #fff;
  box-shadow: 0 0 10px #999;
}

.menu-container {
  margin-bottom: 50px;
}

.sub-container {
  padding: 20px;
  background: repeating-linear-gradient( -45deg, #999, #999 10px, #888 10px, #888 20px);
  border-radius: 2px;
}

.heading {
  color: #000;
  background: #ccc;
  border-bottom: 1px solid #ccc;
  padding: 5px;
}

.indent {
  background: #fff;
  padding: 20px;
}

.icon {
  width: 64px;
  height: 64px;
}

.item {
  background: #fff;
  padding-left: 10px;
  background: #f1f1f1;
  border-top: 1px solid #fff;
  font-size: 30px;
}

.gallery {
  width: 100%;
  *width: 99.94877049180327%;
  margin: 0;
  padding: 0;
}

.gallery.grid li {
  margin: 2px 5px;
}

.gallery.grid li {
  margin: 2px 5px;
  display: block;
}

.gallery.grid li:hover {
  background: #ccc;
}

.gallery.grid li {
  display: inline-block;
  border-top: 1px solid #eee;
  border-right: 1px solid #ccc;
  border-bottom: 1px solid #ccc;
  border-left: 1px solid #eee;
  padding: 6px;
  position: relative;
  -moz-box-sizing: border-box;
  border-radius: 3px 3px 3px 3px;
  background: #fff;
}

.gallery a {
  display: block;
}

<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" />
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.6.3/css/font-awesome.min.css">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js"></script>
<div class="container-fluid">

  <div>
    <span class="toggler btn btn-primary btn-lg" data-selector="parent_">Toggle</span>
  </div>

  <hr />

  <!-- first section -->

  <div id="activities" class="menu-container">
    <h1 class="heading">
      <a href="javascript:;" onclick="HideShow(this,'parent_activities')">
        <i class="fa fa-minus" aria-hidden="true"></i>
      </a> Activities
    </h1>
    <div id="parent_activities" class="sub-container">
      <ul class="gallery grid">
        <li>
          <a href="#"><img title="jack-o-lantern - 🎃" src="https://cdn.jsdelivr.net/emojione/assets/svg/1f383.svg" class="icon" role="presentation"></a>
        </li>
      </ul>
    </div>
  </div>

  <!-- second section -->

  <div id="animals-nature" class="menu-container">
    <h1 class="heading">
      <a href="javascript:;" onclick="HideShow(this,'parent_animals-nature')">
        <i class="fa fa-minus" aria-hidden="true"></i>
      </a> Animals & Nature
    </h1>
    <div id="parent_animals-nature" class="sub-container">
      <ul class="gallery grid">
        <li>
          <a href="#"><img title="monkey face - 🐵" src="https://cdn.jsdelivr.net/emojione/assets/svg/1f435.svg" class="icon" role="presentation"></a>
        </li>
      </ul>
    </div>
  </div>

</div>

代码工作正常，因为蓝色的 Toggle 按钮显示和隐藏其下方的 DIV。

但是，我遇到的问题是，当 DIV 折叠时，我无法单击蓝色加号图标来单独展开 div。再次展开它们的唯一方法是使用切换按钮，而不是能够使用蓝色加号图标上的链接。

可能无法做我想做的事，但我觉得我可能离我不远了，但我正在努力弄清楚如何继续，因为我正在使用我以前的 SO 中提供的解决方案问题，而不是一个“真正的”程序员并不真正理解解决方案中的 JS 代码是如何工作的，我只知道它有一个小问题。

Answer 1

不起作用的主要原因是您更改了与例如内联的显示值

 tbl.style.display = "none";`

由于内联样式通常具有更高的特异性，它们会覆盖外部 CSS 规则(例如此处使用的 d-none)，除非开始在这些样式中使用 !important当然，不建议将其作为此类问题的一般解决方案。

通过做这样的事情，用你的按钮切换类

      if (tbl.className.indexOf("d-none") > -1 ) {
        e.innerHTML = "<i class='fa fa-plus' aria-hidden='true'></i>";
        tbl.classList.remove("d-none");
      } else {
        e.innerHTML = "<i class='fa fa-minus' aria-hidden='true'></i>";
        tbl.classList.add("d-none");
      }

堆栈片段

// So forEach can be used on 'querySelectorAll' and 'getElementsByClassName' collections
		HTMLCollection.prototype.forEach = NodeList.prototype.forEach = Array.prototype.forEach;

		function HideShow(e, itm_id) {
		  var tbl = document.getElementById(itm_id);
		  if (tbl.className.indexOf("d-none") > -1 ) {
			e.innerHTML = "<i class='fa fa-plus' aria-hidden='true'></i>";
			tbl.classList.remove("d-none");
		  } else {
			e.innerHTML = "<i class='fa fa-minus' aria-hidden='true'></i>";
			tbl.classList.add("d-none");
		  }
		}


		// -----------------------------------------------------------
		// NEW Code


		// New toggle links
		let toggles = document.getElementsByClassName('toggler');

		// Attach click event
		toggles.forEach(link => link.addEventListener('click', fnToggleElement))

		// Event handler definition
		function fnToggleElement() {
		  let elements = document.querySelectorAll(`[id^="${this.dataset.selector}"]`)
		  let className = 'd-none'
		  elements.forEach(el => {
			let fas = el.parentElement.closest('.item,.sub-container,.menu-container').querySelectorAll('.fa')
			if (el.classList.contains(className)) {
			  el.classList.remove(className)
			  fas.forEach(fa => {
				fa.classList.remove('fa-plus')
				fa.classList.add('fa-minus')
			  })
			} else {
			  el.classList.add(className)
			  fas.forEach(fa => {
				fa.classList.remove('fa-minus')
				fa.classList.add('fa-plus')
			  })
			}
		  })
		}

body{
  background: #fff;
  margin-top:20px;
}

h1.heading {
  font: 'Oswald';
  text-transform: uppercase;
}

td { background: #f1f1f1; border-bottom:1px solid #ccc; border-right:1px solid #ccc; padding:20px; margin:5px; border-top:1px solid #fff; border-left:1px solid #fff; }



.wrappingmapping {
	margin:20px 0 0 20px;
	border-radius:85px;
	overflow:hidden;
	border:10px solid #fff;
	box-shadow:0 0 10px #999;
}


.menu-container {
  margin-bottom: 50px;
}

.sub-container {
  padding: 20px;
background: repeating-linear-gradient(
  -45deg,
  #999,
  #999 10px,
  #888 10px,
  #888 20px
);
  border-radius: 2px;
}

.heading {
  color: #000;
  background: #ccc;
  border-bottom: 1px solid #ccc;
  padding: 5px;
}

.indent {
  background: #fff;
  padding: 20px;
}

.icon {
  width: 64px;
  height: 64px;
}

.item {
  background: #fff;
  padding-left: 10px;
  background: #f1f1f1;
  border-top: 1px solid #fff;
  font-size: 30px;
}

.gallery {
  width: 100%;
  *width: 99.94877049180327%;
  margin: 0;
  padding: 0;
}

.gallery.grid li {
  margin: 2px 5px;
}

.gallery.grid li {
  margin: 2px 5px;
  display: block;
}

.gallery.grid li:hover {
  background: #ccc;
}

.gallery.grid li {
  display: inline-block;
  border-top: 1px solid #eee;
  border-right: 1px solid #ccc;
  border-bottom: 1px solid #ccc;
  border-left: 1px solid #eee;
  padding: 6px;
  position: relative;
  -moz-box-sizing: border-box;
  border-radius: 3px 3px 3px 3px;
  background: #fff;
}

.gallery a {
  display: block;
}

<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet"/>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.6.3/css/font-awesome.min.css">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js"></script>
	<div class="container-fluid">

		<div>
			<span class="toggler btn btn-primary btn-lg" data-selector="parent_">Toggle</span>	
		</div>

		<hr />

		<!-- first section -->

		<div id="activities" class="menu-container">
			<h1 class="heading">
				<a href="javascript:;" onclick="HideShow(this,'parent_activities')">
					<i class="fa fa-minus" aria-hidden="true"></i>
				</a> Activities 
			</h1>
			<div id="parent_activities" class="sub-container">
				<ul class="gallery grid">	
					<li><a href="#"><img title="jack-o-lantern - 🎃" src="https://cdn.jsdelivr.net/emojione/assets/svg/1f383.svg" class="icon" role="presentation"></a></li>
				</ul>
			</div>
		</div>

		<!-- second section -->

		<div id="animals-nature" class="menu-container">
			<h1 class="heading">
				<a href="javascript:;" onclick="HideShow(this,'parent_animals-nature')">
					<i class="fa fa-minus" aria-hidden="true"></i>
				</a> Animals & Nature 
			</h1>
			<div id="parent_animals-nature" class="sub-container">
				<ul class="gallery grid">	
					<li><a href="#"><img title="monkey face - 🐵" src="https://cdn.jsdelivr.net/emojione/assets/svg/1f435.svg" class="icon" role="presentation"></a></li>
				</ul>
			</div>
		</div>

	</div>