我有一个使用懒惰的线条画家的SVG动画，我想使用它作为一个预加载器。我如何在行动画完成后回顾页面内容（有一个过渡或简单的淡入）？
所以概念是这样的：在登陆时LOAD SVG动画时COMPLETE过渡到页面内容。
<!-- Include lazylinepainter -->
<script src="https://cdn.jsdelivr.net/npm/ [email protected]/lib/lazy-line-painter-1.9.4.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/d3js/5.15.0/d3.min.js"></script>
<script type="text/javascript">
(function(){
document.onreadystatechange = () => {
if (document.readyState === 'complete') {
let el = document.querySelector('#markin2');
let myAnimation = new LazyLinePainter(el, {"ease":"easeLinear","strokeWidth":2.2,"strokeOpacity":1,"strokeColor":"#fff"});
myAnimation.paint();
}
}
})();
</script>
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<circle fill="none" stroke-miterlimit="10" cx="157.828" cy="157.404" r="150.813" data-llp-id="markin2-0" data-llp-duration="2920" data-llp-delay="0" fill-opacity="1" data-llp-stroke-join="" data-llp-stroke-cap=""/>
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</svg>
CSS
body, html {
background: #000;
position: absolute;
width: 100%;
height: 100%;
top:0;
left:0;
margin: 0;
display: flex;
align-items: center;
justify-content: center;
}
#markin2 {
width: 40vw;
height: 40vh;
position: relative;
overflow: visible;
}
.markin2 {
animation: stroke_fill 4s linear forwards, changeColor 2s, forwards;
stroke-dasharray: 1538.2169189453125px;
stroke-dashoffset: 0;
}
@keyframes stroke_fill {
0% {
fill: white;
}
50% {
fill: white;
stroke-dashoffset: 0;
}
100% {
fill: black;
stroke-dashoffset: 0;
}
}
@keyframes changeColor {
from{ fill: rgba(0,0,0,0);}
to{ fill: rgba(0,0,0,1)}
}
下面是SVG动画的例子。
Lazy Line Painter库内置了一些自定义事件，你可以监听这些事件。例如 complete 事件，每当你的动画完成后，就隐藏SVG。每当该事件被调用时，就会隐藏SVG。
在下面的例子中，我添加了这个事件监听器，但也将你的动画包装在一个 Promise 中。这样你就可以等它完成后再做一些事情。还有另一个Promise，它监听的是 load 事件，所以这是一个实际的页面加载器。因此，这是一个实际的页面加载器，SVG不会在页面加载前消失。
在你的HTML中，首先加载SVG，然后加载下面的JS。在 then 回调函数要么删除你的SVG，要么给主体设置一个隐藏类。总之你觉得合适就好。
body,
html {
background: #000;
position: absolute;
width: 100%;
height: 100%;
top: 0;
left: 0;
margin: 0;
display: flex;
align-items: center;
justify-content: center;
}
#markin2 {
width: 20vw;
height: 20vh;
position: relative;
overflow: visible;
}
.markin2 {
animation: stroke_fill 4s linear forwards, changeColor 2s, forwards;
stroke-dasharray: 1538.2169189453125px;
stroke-dashoffset: 0;
}
@keyframes stroke_fill {
0% {
fill: white;
}
50% {
fill: white;
stroke-dashoffset: 0;
}
100% {
fill: black;
stroke-dashoffset: 0;
}
}
@keyframes changeColor {
from {
fill: rgba(0, 0, 0, 0);
}
to {
fill: rgba(0, 0, 0, 1);
}
}
.hsvg {
display: flex;
align-items: center;
justify-content: center;
position: fixed;
width: 100%;
height: 100%;
background: #000000;
z-index: 999;
transition: 2000ms ease-in-out;
transition-property: opacity, visibility;
}
body.is-loaded .hsvg {
opacity: 0;
visibility: hidden;
}
.main-content {
color: #fff;
}<script src="https://cdn.jsdelivr.net/npm/[email protected]/lib/lazy-line-painter-1.9.6.min.js"></script>
<!-- Include lazylinepainter -->
<div class="hsvg">
<svg version="1.1" id="markin2" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" width="314.094px" height="314.765px" viewBox="0 0 314.094 314.765" enable-background="new 0 0 314.094 314.765" xml:space="preserve"
data-llp-composed="true" class="lazy-line-painter">
<circle fill="none" stroke-miterlimit="10" cx="157.828" cy="157.404" r="150.813" data-llp-id="markin2-0" data-llp-duration="2920" data-llp-delay="0" fill-opacity="1" data-llp-stroke-join="" data-llp-stroke-cap=""/>
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</svg>
</div>
<script>
const pageLoad = new Promise(resolve => {
window.addEventListener('load', resolve);
});
const animationLoad = new Promise(resolve => {
let el = document.querySelector('#markin2');
let myAnimation = new LazyLinePainter(el, {
"ease": "easeLinear",
"strokeWidth": 2.2,
"strokeOpacity": 1,
"strokeColor": "#fff"
});
myAnimation.paint();
myAnimation.on('complete', resolve);
});
Promise.all([pageLoad, animationLoad]).then(function() {
document.body.classList.add('is-loaded');
console.log('Load event fired and animation done');
});
</script>
<div class="main-content">
<h1>IS THIS THING ON?</h1>
</div>