單頁應用有個無法避免的問題就是首屏加載慢，雖然可以通過<font color=red>gzip、路由懶加載、CDN、提高服務器帶寬</font>等手段，首屏加載速度仍然比傳統多頁應用慢一些。
為了提高用戶體驗，首屏添加loading動畫很有必要，并且實現特別簡單。
vue-cli3生成的項目中，打開index.html會發現如下代碼
<body>
<noscript>
<strong>We're sorry but doesn't work properly without JavaScript enabled. Please enable it to continue.</strong>
</noscript>
<div id="app"></div>
<!-- built files will be auto injected -->
</body>
我們只需要在這個div中插入loading代碼即可,vue初始化完成后會自動替換
<div id="app">此處插入loading代碼</div>
以下是我實現的一種動畫效果，可自行替換
image
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge"/>
<meta http-equiv="X-UA-Compatible" content="chrome=1"/>
<link rel="icon" href="<%= BASE_URL %>favicon.ico">
<link rel="stylesheet" type="text/css" >
<title>demo</title>
<style>
.spinner {
margin: 100px auto;
width: 50px;
height: 60px;
text-align: center;
font-size: 10px;
}
.spinner > div {
background-color: #FE3C71;
height: 100%;
width: 6px;
display: inline-block;
-webkit-animation: stretchDelay 1.2s infinite ease-in-out;
animation: stretchDelay 1.2s infinite ease-in-out;
}
.spinner .rect2 {
-webkit-animation-delay: -1.1s;
animation-delay: -1.1s;
}
.spinner .rect3 {
-webkit-animation-delay: -1.0s;
animation-delay: -1.0s;
}
.spinner .rect4 {
-webkit-animation-delay: -0.9s;
animation-delay: -0.9s;
}
.spinner .rect5 {
-webkit-animation-delay: -0.8s;
animation-delay: -0.8s;
}
@-webkit-keyframes stretchDelay {
0%, 40%, 100% {
-webkit-transform: scaleY(0.4)
}
20% {
-webkit-transform: scaleY(1.0)
}
}
@keyframes stretchDelay {
0%, 40%, 100% {
transform: scaleY(0.4);
-webkit-transform: scaleY(0.4);
}
20% {
transform: scaleY(1.0);
-webkit-transform: scaleY(1.0);
}
}
</style>
</head>
<body>
<noscript>
<strong>We're sorry but demo doesn't work properly without JavaScript enabled. Please enable it to continue.</strong>
</noscript>
<div id="app">
<div class="spinner">
<div class="rect1"></div>
<div class="rect2"></div>
<div class="rect3"></div>
<div class="rect4"></div>
<div class="rect5"></div>
</div>
</div>
<!-- built files will be auto injected -->
</body>
</html>
