Question

如何用css3绘制一个圆的loading转圈动画

Answer 1

具体css代码如下:
$width: 64px;
$height: 64px;
$dotWidth: 10px;
$dotHeight: 10px;
$radius: 5px;
$offset: 9.37px;

@function getLeft( $x ) {
@return ($width/4)*$x;
}

@function getTop( $y ) {
@return ($height/4)*$y;
}

@keyframes changeOpacity {
from { opacity: 1; }
to { opacity: .2; }
}

.q-loading {
position: fixed;
top: 0;
left: 0;
right: 0;
bottom: 0;
.q-loading-overlay {
position: fixed;
top: 0;
left: 0;
right: 0;
bottom: 0;
background-color: rgba(255, 255, 255, .5);
}
.q-loading-content {
position: absolute;
left: 50%;
top: 50%;
transform: translate(-50%, -50%);
width: $width;
height: $height;
z-index: 2;
}
.dot {
width: 10px;
height: 10px;
position: absolute;
background-color: #0033cc;
border-radius: 50% 50%;
opacity: 1;
animation: changeOpacity 1.04s ease infinite;
}
.dot1 {
left: 0;
top: 50%;
margin-top: -$radius;
animation-delay: 0.13s;
}
.dot2 {
left: $offset;
top: $offset;
animation-delay: 0.26s;
}
.dot3 {
left: 50%;
top: 0;
margin-left: -$radius;
animation-delay: 0.39s;
}
.dot4 {
top: $offset;
right: $offset;
animation-delay: 0.52s;
}
.dot5 {
right: 0;
top: 50%;
margin-top: -$radius;
animation-delay: 0.65s;
}
.dot6 {
right: $offset;
bottom: $offset;
animation-delay: 0.78s;
}
.dot7 {
bottom: 0;
left: 50%;
margin-left: -$radius;
animation-delay: 0.91s;
}
.dot8 {
bottom: $offset;
left: $offset;
animation-delay: 1.04s;
}
}

代码使用scss定义了大圆和小圆圈的半径，不管改成多大只需要更改变量，下面样式无需改变。