纯 CSS 实现十个还不错的 Loading 效果
作者:Jimmy
https://juejin.cn/post/7080542771387301896
在推特上面看到 T. Afif[1] 介绍的十个 Loading
效果。如上图。
Yeah,很赞哦,挺实用的,遂记录下来。
为保证运行正常,咱先规定下:
* {
box-sizing: border-box;
}
1. 平滑加载
<div class="progress-1"></div>
.progress-1 {
width:120px;
height:20px;
background:
linear-gradient(#000 0 0) 0/0% no-repeat
#ddd;
animation:p1 2s infinite linear;
}
@keyframes p1 {
100% {background-size:100%}
}
linear-gradient(#000 0 0)
你可以理解为linear-gradient(#000 0 100%)
,如果还不熟悉,复制linear-gradient(#000 0 50%, #f00 50% 0)
,替换原先的部分跑一下。觉得linear-gradient(#000 0 0)
别扭的话,直接写#000
即可。0/0%
是background-position: 0;/background-size: 0;
的简写。
2. 按步加载
<div class="progress-2"></div>
.progress-2 {
width:120px;
height:20px;
border-radius: 20px;
background:
linear-gradient(orange 0 0) 0/0% no-repeat
lightblue;
animation:p2 2s infinite steps(10);
}
@keyframes p2 {
100% {background-size:110%}
}
steps(10)
是step(10, end)
的简写,指明刚开始没有,所以有第2点的处理100% {background-size:110%}
添加多一个step
的百分比,上面的step
是10
,所以是100% + (1/10)*100% = 110%
3. 条纹加载
<div class="progress-3"></div>
.progress-3 {
width:120px;
height:20px;
border-radius: 20px;
background:
repeating-linear-gradient(135deg,#f03355 0 10px,#ffa516 0 20px) 0/0% no-repeat,
repeating-linear-gradient(135deg,#ddd 0 10px,#eee 0 20px) 0/100%;
animation:p3 2s infinite;
}
@keyframes p3 {
100% {background-size:100%}
}
repeating-linear-gradient(135deg,#ddd 0 10px,#eee 0 20px) 0/100%;
画出灰色的斑马线条纹,repeating-linear-gradient(135deg,#f03355 0 10px,#ffa516 0 20px) 0/0% no-repeat
则是进度条加载的条纹。
4. 虚线加载
<div class="progress-4"></div>
.progress-4 {
width:120px;
height:20px;
-webkit-mask:linear-gradient(90deg,#000 70%,#0000 0) 0/20%;
background:
linear-gradient(#000 0 0) 0/0% no-repeat
#ddd;
animation:p4 2s infinite steps(6);
}
@keyframes p4 {
100% {background-size:120%}
}
-webkit-mask
默认有值 repeat
,不然遮罩不会有五个。
5. 电池加载
<div class="progress-5"></div>
.progress-5 {
width:80px;
height:40px;
border:2px solid #000;
padding:3px;
background:
repeating-linear-gradient(90deg,#000 0 10px,#0000 0 16px)
0/0% no-repeat content-box content-box;
position: relative;
animation:p5 2s infinite steps(6);
}
.progress-5::before {
content:"";
position: absolute;
top: 50%;
left:100%;
transform: translateY(-50%);
width:10px;
height: 10px;
border: 2px solid #000;
}
@keyframes p5 {
100% {background-size:120%}
}
原作者对 .progress-5::before
伪元素实现如下:
.progress-5::before {
content:"";
position: absolute;
top:-2px;
bottom:-2px;
left:100%;
width:10px;
background:
linear-gradient(
#0000 calc(50% - 7px),#000 0 calc(50% - 5px),
#0000 0 calc(50% + 5px),#000 0 calc(50% + 7px),#0000 0) left /100% 100%,
linear-gradient(#000 calc(50% - 5px),#0000 0 calc(50% + 5px),#000 0) left /2px 100%,
linear-gradient(#0000 calc(50% - 5px),#000 0 calc(50% + 5px),#0000 0) right/2px 100%;
background-repeat:no-repeat;
}
#0000 是透明,同等 transparent
6. 内嵌加载
这名字起得有些不贴切,不过不重要,读者看图自然理解。
<div class="progress-6"></div>
.progress-6 {
width:120px;
height:22px;
border-radius: 20px;
color: #514b82;
border:2px solid;
position: relative;
}
.progress-6::before {
content:"";
position: absolute;
margin:2px;
inset:0 100% 0 0;
border-radius: inherit;
background: #514b82;
animation:p6 2s infinite;
}
@keyframes p6 {
100% {inset:0}
}
inset:0 100% 0 0;
右边内缩 100%
,所以在 keyframes
部分需要将 inset
设置为 0
。
7. 珠链加载
<div class="progress-7"></div>
.progress-7 {
width:120px;
height:24px;
-webkit-mask:
radial-gradient(circle closest-side,#000 94%,#0000) 0 0/25% 100%,
linear-gradient(#000 0 0) center/calc(100% - 12px) calc(100% - 12px) no-repeat;
background:
linear-gradient(#25b09b 0 0) 0/0% no-repeat
#ddd;
animation:p7 2s infinite linear;
}
@keyframes p7 {
100% {background-size:100%}
}
遮罩 -webkit-mask
中 radial-gradient
是将宽度四等份,每份以最小 closest-side
的边为直径画圆。
8. 斑马线加载
<div class="progress-8"></div>
.progress-8 {
width:60px;
height:60px;
border-radius: 50%;
-webkit-mask:linear-gradient(0deg,#000 55%,#0000 0) bottom/100% 18.18%;
background:
linear-gradient(#f03355 0 0) bottom/100% 0% no-repeat
#ddd;
animation:p8 2s infinite steps(7);
}
@keyframes p8 {
100% {background-size:100% 115%}
}
对 linear-gradient
描绘的角度做调整,再加上蒙版。
9. 水柱加载
<div class="progress-9"></div>
.progress-9 {
--r1: 154%;
--r2: 68.5%;
width:60px;
height:60px;
border-radius: 50%;
background:
radial-gradient(var(--r1) var(--r2) at top ,#0000 79.5%,#269af2 80%) center left,
radial-gradient(var(--r1) var(--r2) at bottom,#269af2 79.5%,#0000 80%) center center,
radial-gradient(var(--r1) var(--r2) at top ,#0000 79.5%,#269af2 80%) center right,
#ccc;
background-size: 50.5% 220%;
background-position: -100% 0%,0% 0%,100% 0%;
background-repeat:no-repeat;
animation:p9 2s infinite linear;
}
@keyframes p9 {
33% {background-position: 0% 33% ,100% 33% ,200% 33% }
66% {background-position: -100% 66%,0% 66% ,100% 66% }
100% {background-position: 0% 100%,100% 100%,200% 100%}
}
radial-gradient
画出水平面的波动,就三个圆。var(--r1)
直接调用定义好的属性值。技能 get
...
10. 信号加载
<div class="progress-10"></div>
.progress-10 {
width:120px;
height:60px;
border-radius:200px 200px 0 0;
-webkit-mask:repeating-radial-gradient(farthest-side at bottom ,#0000 0,#000 1px 12%,#0000 calc(12% + 1px) 20%);
background:
radial-gradient(farthest-side at bottom,#514b82 0 95%,#0000 0) bottom/0% 0% no-repeat
#ddd;
animation:p10 2s infinite steps(6);
}
@keyframes p10 {
100% {background-size:120% 120%}
}
用 repeating-radial-gradient
方法画出环状的蒙版遮罩。radial-gradient
从底部向上圆形渐变填充。
Uha,看了这么多骚操作,你学废了吗?
参考和后话
原文:10 CSS-only loaders ready to use![2]
参考资料
T. Afif: https://twitter.com/ChallengesCss
[2]10 CSS-only loaders ready to use!: https://twitter.com/ChallengesCss/status/1500437014616940546?cxt=HHwWhIC5gfzgz9IpAAAA