悬停菜单项

如何解决悬停菜单项

帮我实现一个悬停菜单。 底线是，当悬停在菜单项上时，红色圆圈会平滑地接近悬停项。当光标离开该点时，圆会平滑地上升到其坐标。 预先感谢。

nav{
  position: relative;
}
.circle{
  height: 10px;
  width: 10px;
  display: inline-blick;
  background-color: red;
  border-radius: 50px;
  position: absolute;
  top: 50%;
  left: 0;
  transform: translateY(-50%);
}
.menu{
  margin: 0;
  padding: 0 0 0 30px;
  height: audo;
  width: 100%;
  display: inline-blick;
  list-style: none;  
}
.menu li{
  cursor: pointer;
}

<nav>
  <div class="circle"></div>
  <ul class="menu">
  <li>Menu 1</li>
  <li>Menu 2</li>
  <li>Menu 3</li>
</ul>
</nav>

Example here

解决方法

此脚本的工作方式：

获取<li>中的所有id="menu"项，并将它们分别设置为mouseover和mouseout的“事件监听器”

将鼠标悬停在<li>元素上时，脚本将从顶部和高度开始移动其位置。这些坐标以内联样式传递到#circle元素。

当鼠标光标从mouseout元素中移至<li>时，将删除内联样式，并且红点将返回其原始位置。

您可以从CSS transition: 0.8s;

更改移动速度

var menu = document.getElementById('menu');
var li = menu.getElementsByTagName('li');
var dot = document.getElementById('circle');

for (var i = 0; i < li.length; i++) {
    li[i].addEventListener("mouseover",function () {
        setAnimation(this);
    });

    li[i].addEventListener("mouseout",function () {
        dot.setAttribute('style','');
    });
}

function setAnimation(el) {
    var pos = el.offsetTop;
    var h = el.offsetHeight;
    dot.setAttribute('style','top:' + (pos + h / 2) + 'px;');
}

nav {
    position: relative;
}

#circle {
    height: 10px;
    width: 10px;
    display: inline-blick;
    background-color: red;
    border-radius: 50px;
    position: absolute;
    top: 50%;
    left: 0;
    transform: translateY(-50%);

    -webkit-transition: 0.8s;
    -moz-transition: 0.8s;
    transition: 0.8s;
}

#menu {
    margin: 0;
    padding: 0 0 0 30px;
    height: audo;
    width: 100%;
    display: inline-blick;
    list-style: none;
}

#menu li {
    cursor: pointer;
}

<nav>
    <div id="circle"></div>
    <ul id="menu">
        <li>Menu 1</li>
        <li>Menu 2</li>
        <li>Menu 3</li>
        <li>Menu 4</li>
        <li>Menu 5</li>
    </ul>
</nav>

,

您可以通过几种方法来执行此操作。我在下面创建了一些方法。您也可以在给定的代码中添加动画。 我正在考虑div <div class="circle"></div> 并非必须放置在<ul> 标签

之前

function chbg(elem,color) {
elem.firstChild.style.backgroundColor=color;
}
var circle = '<div class="circle" style="background-color: red;"></div>';
var menu = document.getElementsByClassName('menu2')[0];
for (var i = 0; i < menu.children.length; i++) {
    menu.children[i].addEventListener("mouseout",function () {
      this.innerHTML =this.innerHTML.replaceAll(circle,'')
    });

    menu.children[i].addEventListener("mouseover",function () {
if(this.innerHTML.indexOf(circle)==-1)
       this.innerHTML =this.innerHTML+circle
    });
}

nav{
  position: relative;
}

.circle{
  float:left;
  height: 10px;
  width: 10px;
  display: inline-blick;
  border-radius: 50px;
  top: 50%;
  left: 0;
}
.menu,.menu2,.menu3{
  margin: 0;
  padding: 0 0 0 30px;
  height: audo;
  width: 100%;
  display: inline-blick;
  list-style: none;  
}

.menu3 li:before { 
opacity:0;
content: ''; 
background-color: red;
float:left;
  height: 10px;
  width: 10px;
  display: inline-blick;
  border-radius: 50px;
  top: 50%;
  left: 0;
  }
  .menu3 li:hover:before{
  opacity:1;
  }

<h1>method 1 using javascript</h1>
<nav>
  <ul class="menu">
  <li onmouseover="chbg(this,'red')" onmouseout="chbg(this,'white')"><div class="circle"></div>Menu 1</li>
  <li onmouseover="chbg(this,'white')"><div class="circle"></div>Menu 2</li>
  <li onmouseover="chbg(this,'white')"><div class="circle"></div>Menu 3</li>
</ul>
</nav>

<h1>method 2 using javascript</h1>
<nav>
  <ul class="menu2">
  <li>Menu 1</li>
  <li>Menu 2</li>
  <li>Menu 3</li>
</ul>
</nav>

<h1>method 3 using CSS</h1>
<nav>
  <ul class="menu3">
  <li>Menu 1</li>
  <li>Menu 2</li>
  <li>Menu 3</li>
</ul>
</nav>