javascript - 保持下拉列表向下滑动直到鼠标移到子项上的问题

Question

能否请您看一下这个演示，让我知道如何强制 .droper向下滑动直到鼠标仍然在所有子项上<li>是吗？

从演示中可以看出 .droper鼠标一离开.menu-itemb就开始向上滑动(这对我来说很有意义!)但我需要保持它可用，直到用户在下拉菜单上浏览

$(document).ready(function(){
  $(".menu-itemb").mouseover(function(){
  
   $(".droper").stop().slideDown("slow");
  });
  $(".menu-itemb").mouseout(function(){
   $(".droper").slideUp("slow");
  });
 });

body {
  background: #1f1f1f;
}

.site-navigation {
	display: block;
	font-family: 'Titillium Web', sans-serif;
	font-size: 16px;
	font-weight: bold;
	margin: 40px;
}

.site-navigation ul {
  background: #3498DB;
	list-style: none;
	margin: 0;
	padding-left: 0;
}

.site-navigation li {
	color: #fff;
  background: #3498DB;
	display: block;
	float: left;
	margin: 0 2px 0 0;
	padding: 12px;
	position: relative;
	text-decoration: none;
	text-transform: uppercase;
}
  
.site-navigation li a {
  color: #fff;
  text-decoration: none;
  display: block;
}

.site-navigation li:hover {
	@include transition(background, 0.2s);
	background: #52a6df;
	cursor: pointer;
}

.site-navigation ul li ul {
	background: #52a6df;
	display:none;
	float: left;
  min-width: 150px;
	position: absolute;
  transition: visibility 0.65s ease-in;
  margin-top:12px;
	left: 0;
	z-index: 999;
}

.site-navigation ul li:hover > ul,
.site-navigation ul li ul:hover {
   visibility: visible;
}

.site-navigation ul li ul li {
	clear: both;
	padding: 5px 0 5px 18px;
  width: 100%;
}

.site-navigation ul li ul li:hover {
	background: #74b7e4;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js"></script>
<nav id="navigation" class="site-navigation" role="navigation">
  <ul class="menu">
    <li class="menu-item"><a href="#">News</a></li>
    <li class="menu-itemb"><a href="#">Snippets</a>
      <ul class="droper">
        <li class="menu-item sub-menu"><a href="#">CSS</a></li>
        <li class="menu-item sub-menu"><a href="#">HTML</a></li>
        <li class="menu-item sub-menu"><a href="#">jQuery</a></li>
        <li class="menu-item sub-menu"><a href="#">PHP</a></li>
        <li class="menu-item sub-menu"><a href="#">WordPress</a></li>
      </ul>
    </li>
    <li class="menu-item"><a href="#">Inspiration</a></li>
    <li class="menu-item"><a href="#">Tools</a></li>
    <li class="menu-item"><a href="#">Tutorials</a></li>
  </ul>
</nav>

Answer 1

您在 slideUp 之前缺少一个 .stop()。没有它，当你在元素之间移动鼠标时，动画将被触发并执行到结束......

$(document).ready(function(){
  $(".menu-itemb").mouseover(function(){
  
   $(".droper").stop().slideDown("slow");
  });
  $(".menu-itemb").mouseout(function(){
   $(".droper").stop().slideUp("slow");
  });
 });

body {
  background: #1f1f1f;
}

.site-navigation {
	display: block;
	font-family: 'Titillium Web', sans-serif;
	font-size: 16px;
	font-weight: bold;
	margin: 40px;
}

.site-navigation ul {
  background: #3498DB;
	list-style: none;
	margin: 0;
	padding-left: 0;
}

.site-navigation li {
	color: #fff;
  background: #3498DB;
	display: block;
	float: left;
	margin: 0 2px 0 0;
	padding: 12px;
	position: relative;
	text-decoration: none;
	text-transform: uppercase;
}
  
.site-navigation li a {
  color: #fff;
  text-decoration: none;
  display: block;
}

.site-navigation li:hover {
	@include transition(background, 0.2s);
	background: #52a6df;
	cursor: pointer;
}

.site-navigation ul li ul {
	background: #52a6df;
	display:none;
	float: left;
  min-width: 150px;
	position: absolute;
  transition: visibility 0.65s ease-in;
  margin-top:12px;
	left: 0;
	z-index: 999;
}

.site-navigation ul li:hover > ul,
.site-navigation ul li ul:hover {
   visibility: visible;
}

.site-navigation ul li ul li {
	clear: both;
	padding: 5px 0 5px 18px;
  width: 100%;
}

.site-navigation ul li ul li:hover {
	background: #74b7e4;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js"></script>
<nav id="navigation" class="site-navigation" role="navigation">
  <ul class="menu">
    <li class="menu-item"><a href="#">News</a></li>
    <li class="menu-itemb"><a href="#">Snippets</a>
      <ul class="droper">
        <li class="menu-item sub-menu"><a href="#">CSS</a></li>
        <li class="menu-item sub-menu"><a href="#">HTML</a></li>
        <li class="menu-item sub-menu"><a href="#">jQuery</a></li>
        <li class="menu-item sub-menu"><a href="#">PHP</a></li>
        <li class="menu-item sub-menu"><a href="#">WordPress</a></li>
      </ul>
    </li>
    <li class="menu-item"><a href="#">Inspiration</a></li>
    <li class="menu-item"><a href="#">Tools</a></li>
    <li class="menu-item"><a href="#">Tutorials</a></li>
  </ul>
</nav>