CSS动画延迟未触发答案

【问题标题】：CSS animation delay not triggeringCSS动画延迟未触发
【发布时间】：2017-01-11 06:10:50
【问题描述】：

只是想知道为什么这个简单的动画延迟似乎不起作用。我只想在元素淡入之前延迟 7 秒。很简单，我确定，但现在已经看了很长时间了。

.box1 {
  width: 100px;
  margin: 0 auto;
  position: relative;
  border: 1px solid blue;
}
.box2 {
   background: red;
  color: black;
  text-align: center;
  animation-delay: 7s;
  -webkit-animation-delay: 7s;
  animation: fadein 2s linear;
  -webkit-animation: fadein 2s linear;
 
}
@keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
@-webkit-keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

<div class= "box1">

  <div class="box2">

    <p>some text</p>

  </div>

</div>

【问题讨论】：

标签： css animation css-animations

【解决方案1】：

把动画延迟放在动画后面，因为延迟需要附加到有问题的动画上（顺序很重要）：

.box1 {
  width: 100px;
  margin: 0 auto;
  position: relative;
  border: 1px solid blue;
}
.box2 {
   background: red;
  color: black;
  text-align: center;
  -webkit-animation: fadein 2s linear;
   animation: fadein 2s linear; 
  -webkit-animation-delay: 7s;
   animation-delay: 7s;
 
}
@keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
@-webkit-keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

<div class="box1">

  <div class="box2">

    <p>some text</p>

  </div>

</div>

或者使用简写方式，删除animation-delay: 7s; 和-webkit-animation-delay: 7s; 并将延迟时间添加到animation 属性，如下所示：

-webkit-animation:fadein 2s linear 7s;
 animation:fadein 2s linear 7s;

.box1 {
  width: 100px;
  margin: 0 auto;
  position: relative;
  border: 1px solid blue;
}
.box2 {
  background: red;
  color: black;
  text-align: center;
  -webkit-animation: fadein 2s linear 7s;
  animation: fadein 2s linear 7s;
}
@keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
@-webkit-keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

<div class="box1">

  <div class="box2">

    <p>some text</p>

  </div>

</div>

【讨论】：

非常感谢这位朋友

【解决方案2】：

尝试使用长格式 animation 属性：

animation-delay
animation-name
animation-duration
animation-timing-function

.box1 {
  width: 100px;
  margin: 0 auto;
  position: relative;
  border: 1px solid blue;
}
.box2 {
   background: red;
  color: black;
  text-align: center;
  opacity: 0;
  -webkit-animation-delay: 7s;
  -webkit-animation-name: fadein;
  -webkit-animation-duration: 2s; 
  -webkit-animation-timing-function: linear;
  animation-delay: 7s;
  animation-name: fadein; 
  animation-duration: 2s;
  animation-timing-function: linear;
 
}
@-webkit-keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
@keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

<div class= "box1">

  <div class="box2">

    <p>some text</p>

  </div>

</div>

【讨论】：

【解决方案3】：

下面的代码有效，我将盒子的初始不透明度设置为 0，因此它“淡入”，而且动画延迟属性似乎只有在动画本身之后声明它才有效。我还添加了动画填充模式：转发；保持动画后显示的框。

.box1 {
  width: 100px;
  margin: 0 auto;
  position: relative;
  border: 1px solid blue;
}
.box2 {
   background: red;
  color: black;
  text-align: center;
  animation: fadein 2s linear;
  -webkit-animation: fadein 2s linear;
  animation-delay: 7s;
  -webkit-animation-delay: 7s;
  animation-fill-mode: forwards;
  -webkit-animation-fill-mode: forwards;
  opacity: 0;
 
}
@keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
@-webkit-keyframes fadein {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

<div class= "box1">

  <div class="box2">

    <p>some text</p>

  </div>

</div>

【讨论】：