我们在开发中经常遇到一种场景,就是给元素加提示信息,就是鼠标移入到盒子上面时,会出现提示信息这一功能,如果我们给盒子加了hover,当鼠标移入到盒子上时,让他往上移动5px,即transform: translateY(-5px), 同时还让提示信息展示出来,此时受到transform的影响,提示信息会被父盒子遮挡住。代码如下:
<template>
<div class="container">
<div
class="item"
v-for="item in 30"
@mouseenter="showTooltip"
@mouseleave="hideTooltip"
>
<div class="tooltip"></div>
<span>{{ item }}</span>
</div>
</div>
</template>
<style>
.container {
display: flex;
flex-wrap: wrap;
width: 1145px;
margin: 0 auto;
padding: 10px;
}
.item {
position: relative;
display: flex;
justify-content: center;
align-items: center;
width: 120px;
height: 120px;
background-color: #eceff7;
border-radius: 10px;
margin: 10px;
box-shadow: 0 3px 5px 2px rgba(0, 0, 0, 0.1);
cursor: pointer;
transition: all 0.5s ease;;
}
.item .tooltip {
display: none;
width: 100px;
height: 30px;
background-color: #000;
border-radius: 6px;
position: absolute;
bottom: -50px;
z-index: 10;
}
.item .tooltip::after {
position: absolute;
left: 0;
top: -25px;
width: 0;
height: 0;
left: 50%;
transform: translateX(-50%);
border-left: 12px solid transparent;
border-right: 12px solid transparent;
border-top: 15px solid transparent;
border-bottom: 15px solid #000;
content: "";
z-index: 20px;
}
.item:hover {
transform: translateY(-5px);
}
.item:hover .tooltip {
display: block;
}
</style>
我们可以看到,我们给tooltip设置了z-index值为10,但是黑色提示信息依然被挡住了,原因时当hover时,执行了transform, 会改变元素的层级,
此时我们只需要给 .item:hover 加上一句 z-index: 1, 保证hover的时候,层级比item更低,就能解决这个问题。
<template>
<div class="container">
<div
class="item"
v-for="item in 30"
@mouseenter="showTooltip"
@mouseleave="hideTooltip"
>
<div class="tooltip"></div>
<span>{{ item }}</span>
</div>
</div>
</template>
<style>
.container {
display: flex;
flex-wrap: wrap;
width: 1145px;
margin: 0 auto;
padding: 10px;
}
.item {
position: relative;
display: flex;
justify-content: center;
align-items: center;
width: 120px;
height: 120px;
background-color: #eceff7;
border-radius: 10px;
margin: 10px;
box-shadow: 0 3px 5px 2px rgba(0, 0, 0, 0.1);
cursor: pointer;
transition: all 0.5s ease;;
}
.item .tooltip {
display: none;
width: 100px;
height: 30px;
background-color: #000;
border-radius: 6px;
position: absolute;
bottom: -50px;
z-index: 10;
}
.item .tooltip::after {
position: absolute;
left: 0;
top: -25px;
width: 0;
height: 0;
left: 50%;
transform: translateX(-50%);
border-left: 12px solid transparent;
border-right: 12px solid transparent;
border-top: 15px solid transparent;
border-bottom: 15px solid #000;
content: "";
z-index: 20px;
}
.item:hover {
z-index: 1; /* 保证hover的时候z-index层级更低 */
transform: translateY(-5px);
}
.item:hover .tooltip {
display: block;
}
</style>
此时我们再看效果: