>我这里有以下代码示例:
$(document).ready(function() {
$('.children a.txtlink').on("click", function(e) {
// toggle the icons when the text link is pressed
jQuery(this).parent().find('ul:first').toggle(); // toggle the next UL
if (jQuery(this).parent().find('i').hasClass("fa-chevron-down")) {
jQuery(this).parent().find('i').removeClass("fa-chevron-down").addClass("fa-chevron-up");
} else {
jQuery(this).parent().find('i').removeClass("fa-chevron-up").addClass("fa-chevron-down");
}
e.stopPropagation();
e.preventDefault();
});
$('.children i.arrows').on("click", function(e) {
// toggle the icons when the chevron is pressed
jQuery(this).parent().find('ul:first').toggle(); // toggle the next UL
if (jQuery(this).hasClass("fa-chevron-down")) {
jQuery(this).removeClass("fa-chevron-down").addClass("fa-chevron-up");
} else {
jQuery(this).removeClass("fa-chevron-up").addClass("fa-chevron-down");
}
e.stopPropagation();
e.preventDefault();
});
});
.navbar_menu {
background: #222222;
}
.menu {
border-top: 1px solid #2D2D2D;
}
.menu ul {
padding: 0;
margin: 0;
}
.menu li {
list-style: none;
position: relative;
}
.menu li i {
padding-right: 3px;
}
.menu a.txtlink {
color: #ccc;
display: block;
font-size: 16px;
padding: 10px;
padding-right: 0;
border-bottom: 1px solid #2D2D2D;
text-decoration: none;
}
.menu a.txtlink:hover {
background: #111111;
color: #ffffff;
text-decoration: none;
}
.menu li.home a.txtlink::before {
content: 'f015';
display: inline-block;
font: normal normal normal 14px/1 FontAwesome;
font-size: inherit;
text-rendering: auto;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
transform: none;
}
.menu ul li {
position: relative;
}
.menu ul li.children i.arrows {
/* needed to show an icon in the mobile menu */
position: absolute;
top: 0;
right: 0;
padding: 14px;
border-left: 1px solid #333333;
margin: 0;
cursor: pointer;
display: block;
color: #CCCCCC;
}
.menu .sub {
display: none;
}
.menu ul li ul li a.txtlink {
padding-left: 20px;
}
.menu ul li ul li ul li a.txtlink {
padding-left: 40px;
}
.menu i.arrows:hover {
background-color: #111111;
}
.menu ul li ul li {
background-color: #333333;
}
<script src="https://code.jquery.com/jquery-3.2.0.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" />
<nav class="navbar_menu">
<div class="menu">
<ul>
<li class="home"><a href="#" class="txtlink">Home</a></li>
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-folder"></i>Menu 1</a>
<ul class="sub">
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-search"></i>Menu 1.1</a>
<ul class="sub">
<li><a href="#" class="txtlink"><i class="fa fa-user"></i>Menu 1.1.1</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-tag"></i>Menu 1.1.2</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink">Menu 1.2</a></li>
<li><a href="#" class="txtlink">Menu 1.3</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-clock-o"></i>Menu 1.4</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-search"></i>Menu 1.5</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa "></i>Menu 2</a></li>
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-folder"></i>Menu 3</a>
<ul class="sub">
<li class="children">
<a href="#" class="txtlink"><i class="fa fa fa-search"></i>Menu 3.1</a>
<ul class="sub">
<li><a href="#" class="txtlink"><i class="fa fa-user"></i>Menu 3.1.1</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-bookmark-o"></i>Menu 3.1.2</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa"></i>Menu 3.2</a></li>
<li><a href="#" class="txtlink"><i class="fa"></i>Menu 3.3</a></li>
<li><a href="#" class="txtlink"><i class="fa fa fa-calendar"></i>Menu 3.4</a></li>
<li><a href="#" class="txtlink"><i class="fa fa fa-search"></i>Menu 3.5</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa fa-comments"></i>Menu 4</a></li>
</ul>
</div>
</nav>
问题是当我使用小箭头展开/缩小菜单并且箭头正确交换时,它工作正常。但是,当我单击文本元素时,菜单中的图标都将替换为箭头。
示例:使用箭头时,搜索图标保留在菜单中。当我单击文本链接时,它被替换为箭头。
我想我在这里使用了错误的 jquery 选择器,但由于我对 jquery 很陌生,所以我无法修复它。那么我的错误是什么?
当我点击箭头时
- 使用
.children()
而不是.find()
来确保只有直接子项包含在查询中。 - 您的点击事件可以组合转换为 1 个具有
$('.children > a.txtlink, .children > i.arrows')
的单个事件侦听器。同样,使用>
直接子选择器确保我们不查询嵌套子项。
它现在应该按预期工作:
$(document).ready(function() {
$('.children > a.txtlink, .children > i.arrows').on("click", function(e) {
// toggle the icons when the text link is pressed
jQuery(this).parent().children('ul:first').toggle(); // toggle the next UL
if (jQuery(this).parent().children('i.arrows').hasClass("fa-chevron-down")) {
jQuery(this).parent().children('i.arrows').removeClass("fa-chevron-down").addClass("fa-chevron-up");
} else {
jQuery(this).parent().children('i.arrows').removeClass("fa-chevron-up").addClass("fa-chevron-down");
}
e.stopPropagation();
e.preventDefault();
});
});
.navbar_menu {
background: #222222;
}
.menu {
border-top: 1px solid #2D2D2D;
}
.menu ul {
padding: 0;
margin: 0;
}
.menu li {
list-style: none;
position: relative;
}
.menu li i {
padding-right: 3px;
}
.menu a.txtlink {
color: #ccc;
display: block;
font-size: 16px;
padding: 10px;
padding-right: 0;
border-bottom: 1px solid #2D2D2D;
text-decoration: none;
}
.menu a.txtlink:hover {
background: #111111;
color: #ffffff;
text-decoration: none;
}
.menu li.home a.txtlink::before {
content: 'f015';
display: inline-block;
font: normal normal normal 14px/1 FontAwesome;
font-size: inherit;
text-rendering: auto;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
transform: none;
}
.menu ul li {
position: relative;
}
.menu ul li.children i.arrows {
/* needed to show an icon in the mobile menu */
position: absolute;
top: 0;
right: 0;
padding: 14px;
border-left: 1px solid #333333;
margin: 0;
cursor: pointer;
display: block;
color: #CCCCCC;
}
.menu .sub {
display: none;
}
.menu ul li ul li a.txtlink {
padding-left: 20px;
}
.menu ul li ul li ul li a.txtlink {
padding-left: 40px;
}
.menu i.arrows:hover {
background-color: #111111;
}
.menu ul li ul li {
background-color: #333333;
}
<script src="https://code.jquery.com/jquery-3.2.0.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" />
<nav class="navbar_menu">
<div class="menu">
<ul>
<li class="home"><a href="#" class="txtlink">Home</a></li>
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-folder"></i>Menu 1</a>
<ul class="sub">
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-search"></i>Menu 1.1</a>
<ul class="sub">
<li><a href="#" class="txtlink"><i class="fa fa-user"></i>Menu 1.1.1</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-tag"></i>Menu 1.1.2</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink">Menu 1.2</a></li>
<li><a href="#" class="txtlink">Menu 1.3</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-clock-o"></i>Menu 1.4</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-search"></i>Menu 1.5</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa "></i>Menu 2</a></li>
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-folder"></i>Menu 3</a>
<ul class="sub">
<li class="children">
<a href="#" class="txtlink"><i class="fa fa fa-search"></i>Menu 3.1</a>
<ul class="sub">
<li><a href="#" class="txtlink"><i class="fa fa-user"></i>Menu 3.1.1</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-bookmark-o"></i>Menu 3.1.2</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa"></i>Menu 3.2</a></li>
<li><a href="#" class="txtlink"><i class="fa"></i>Menu 3.3</a></li>
<li><a href="#" class="txtlink"><i class="fa fa fa-calendar"></i>Menu 3.4</a></li>
<li><a href="#" class="txtlink"><i class="fa fa fa-search"></i>Menu 3.5</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa fa-comments"></i>Menu 4</a></li>
</ul>
</div>
</nav>
首先,在尝试此操作并提供代码方面做得很好。 也就是说,有很多方法可以改善这一点,我没有时间进入,但已经做了一些更改来弥合这一差距:
- 使用变量使代码更高效、更易于阅读。 存储
$(this)
和$(this).parent()
是代码中的两个必备条件 -
问题的核心来自
$parent.find('i').hasClass('fa-chevron-down')
,即在该父级下定位所有<i>
元素,如果有该类,那将是真的。 我很快将其更改为仅查找i.fa-chevron-down
,但使用jQuery.children()
也可能是更好的选择 -
为了避免
$
冲突,避免$(document).ready
并使用jQuery(document).ready
是一个很好的经验法则;然后,如果您调用命名参数,则可以在内部使用该$
;例如.ready(function($){
jQuery(document).ready(function($) {
$('.children a.txtlink').on("click", function(e) {
// toggle the icons when the text link is pressed
var $this = $(this),
$parent = $this.parent(),
$ul = $parent.find('ul:first');
$ul.toggle(); // toggle the next UL
if ($parent.find('i.fa-chevron-down').length) {
$parent.find('i.fa-chevron-down').removeClass("fa-chevron-down").addClass("fa-chevron-up");
} else {
$parent.find('i.fa-chevron-up').removeClass("fa-chevron-up").addClass("fa-chevron-down");
}
e.stopPropagation();
e.preventDefault();
});
$('.children i.arrows').on("click", function(e) {
// toggle the icons when the chevron is pressed
var $this = $(this),
$parent = $this.parent(),
$ul = $parent.find('ul:first');
$ul.toggle(); // toggle the next UL
if ($this.hasClass("fa-chevron-down")) {
$this.removeClass("fa-chevron-down").addClass("fa-chevron-up");
} else {
$this.removeClass("fa-chevron-up").addClass("fa-chevron-down");
}
e.stopPropagation();
e.preventDefault();
});
});
.navbar_menu {
background: #222222;
}
.menu {
border-top: 1px solid #2D2D2D;
}
.menu ul {
padding: 0;
margin: 0;
}
.menu li {
list-style: none;
position: relative;
}
.menu li i {
padding-right: 3px;
}
.menu a.txtlink {
color: #ccc;
display: block;
font-size: 16px;
padding: 10px;
padding-right: 0;
border-bottom: 1px solid #2D2D2D;
text-decoration: none;
}
.menu a.txtlink:hover {
background: #111111;
color: #ffffff;
text-decoration: none;
}
.menu li.home a.txtlink::before {
content: 'f015';
display: inline-block;
font: normal normal normal 14px/1 FontAwesome;
font-size: inherit;
text-rendering: auto;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
transform: none;
}
.menu ul li {
position: relative;
}
.menu ul li.children i.arrows {
/* needed to show an icon in the mobile menu */
position: absolute;
top: 0;
right: 0;
padding: 14px;
border-left: 1px solid #333333;
margin: 0;
cursor: pointer;
display: block;
color: #CCCCCC;
}
.menu .sub {
display: none;
}
.menu ul li ul li a.txtlink {
padding-left: 20px;
}
.menu ul li ul li ul li a.txtlink {
padding-left: 40px;
}
.menu i.arrows:hover {
background-color: #111111;
}
.menu ul li ul li {
background-color: #333333;
}
<script src="https://code.jquery.com/jquery-3.2.0.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" />
<nav class="navbar_menu">
<div class="menu">
<ul>
<li class="home"><a href="#" class="txtlink">Home</a></li>
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-folder"></i>Menu 1</a>
<ul class="sub">
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-search"></i>Menu 1.1</a>
<ul class="sub">
<li><a href="#" class="txtlink"><i class="fa fa-user"></i>Menu 1.1.1</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-tag"></i>Menu 1.1.2</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink">Menu 1.2</a></li>
<li><a href="#" class="txtlink">Menu 1.3</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-clock-o"></i>Menu 1.4</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-search"></i>Menu 1.5</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa "></i>Menu 2</a></li>
<li class="children">
<a href="#" class="txtlink"><i class="fa fa-folder"></i>Menu 3</a>
<ul class="sub">
<li class="children">
<a href="#" class="txtlink"><i class="fa fa fa-search"></i>Menu 3.1</a>
<ul class="sub">
<li><a href="#" class="txtlink"><i class="fa fa-user"></i>Menu 3.1.1</a></li>
<li><a href="#" class="txtlink"><i class="fa fa-bookmark-o"></i>Menu 3.1.2</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa"></i>Menu 3.2</a></li>
<li><a href="#" class="txtlink"><i class="fa"></i>Menu 3.3</a></li>
<li><a href="#" class="txtlink"><i class="fa fa fa-calendar"></i>Menu 3.4</a></li>
<li><a href="#" class="txtlink"><i class="fa fa fa-search"></i>Menu 3.5</a></li>
</ul>
<i class="arrows fa fa-chevron-down"></i>
</li>
<li><a href="#" class="txtlink"><i class="fa fa-comments"></i>Menu 4</a></li>
</ul>
</div>
</nav>