108 lines
2.0 KiB
Markdown
108 lines
2.0 KiB
Markdown
---
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id: 587d78a8367417b2b2512ae3
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title: 使用无限的动画计数制作永不停止的动画
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challengeType: 0
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videoUrl: 'https://scrimba.com/c/cVJDVfq'
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forumTopicId: 301041
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dashedName: animate-elements-continually-using-an-infinite-animation-count
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---
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# --description--
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之前的关卡里介绍了一些动画属性以及 `@keyframes` 规则的用法。 还有一个常用的动画属性是 `animation-iteration-count`，这个属性允许你控制动画循环的次数。 下面是一个例子：
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```css
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animation-iteration-count: 3;
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```
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在这里动画会在运行 3 次后停止，如果想让动画一直运行，可以把值设置成 `infinite`。
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# --instructions--
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把 `animation-iteration-count` 属性改成 `infinite`，使右边的球一直跳跃。
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# --hints--
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`animation-iteration-count` 属性的值应为 `infinite`。
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```js
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assert($('#ball').css('animation-iteration-count') == 'infinite');
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```
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# --seed--
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## --seed-contents--
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```html
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<style>
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#ball {
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width: 100px;
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height: 100px;
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margin: 50px auto;
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position: relative;
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border-radius: 50%;
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background: linear-gradient(
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35deg,
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#ccffff,
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#ffcccc
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);
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animation-name: bounce;
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animation-duration: 1s;
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animation-iteration-count: 3;
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}
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@keyframes bounce{
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0% {
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top: 0px;
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}
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50% {
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top: 249px;
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width: 130px;
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height: 70px;
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}
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100% {
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top: 0px;
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}
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}
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</style>
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<div id="ball"></div>
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```
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# --solutions--
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```html
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<style>
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#ball {
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width: 100px;
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height: 100px;
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margin: 50px auto;
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position: relative;
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border-radius: 50%;
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background: linear-gradient(
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35deg,
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#ccffff,
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#ffcccc
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);
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animation-name: bounce;
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animation-duration: 1s;
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animation-iteration-count: infinite;
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}
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@keyframes bounce{
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0% {
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top: 0px;
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}
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50% {
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top: 249px;
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width: 130px;
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height: 70px;
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}
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100% {
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top: 0px;
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}
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}
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</style>
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<div id="ball"></div>
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```
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