我怀疑问题出在下面JS代码中的第const active = document.querySelector(".accordion.active");行.它似乎没有检索到那个元素.你能帮我调试一下吗？或者我应该用别的东西而不是querySelector？还发现，当点击Accordion元素时，this.classList.add("active");没有向Accordion元素添加"活动类".
document.addEventListener("DOMContentLoaded", function(event) {
var acc = document.getElementsByClassName("accordion");
var i;
for (i = 0; i < acc.length; i++) {
acc[i].addEventListener("click", function() {
const active = document.querySelector(".accordion.active");
console.log(active);
if (active) {
active.classList.remove('active'); // remove active class from accordions
}
this.classList.add("active"); // add it to this one
this.classList.toggle("active");
var panel = this.nextElementSibling;
if (panel.style.display === "block") {
panel.style.display = "none";
} else {
panel.style.display = "block";
}
});
}
});.accordion {
background-color: #eee;
color: #444;
cursor: pointer;
padding: 1.5rem;
width: 100%;
border: none;
text-align: left;
outline: none;
font-size: 15px;
transition: 0.4s;
}
.active,
.accordion:hover {
background-color: #ccc;
}
.panel {
padding: 0 18px;
display: none;
background-color: white;
overflow: hidden;
background: red;
}
.active+.panel {
display: block;
}<div class="row">
<button class="accordion"><div class="question"><?php echo $label; ?></div></button>
<div class="panel">
<p class="answer">
<?php echo $answer; ?>
</p>
</br>
</div>
</div>
<div class="row">
<button class="accordion"><div class="question"><?php echo $label; ?></div></button>
<div class="panel">
<p class="answer">
<?php echo $answer; ?>
</p>
</br>
</div>
</div>