幻灯片图片消失

Question

我有一个 CSS + Javascripts 幻灯片，取自 W3Schools website example。

这是适用于我的网络应用程序的代码（几乎相同）：

$(document).ready(function() {
  var slideIndex = 1;

  function showSlides(n) {
    var slides = $(".mySlides");
    var i;

    if (n > slides.length) {
      slideIndex = 1;
    }

    if (n < 1) {
      slideIndex = slides.length;
    }

    for (i = 0; i < slides.length; i++) {
      slides[i].style.display = "none";
    }

    slides[slideIndex - 1].style.display = "block";
  }

  function plusSlides(n) {
    showSlides(slideIndex += n);
  }

  showSlides(slideIndex);

  $(".prev").click(function() {
    plusSlides(-1);
  });

  $(".next").click(function() {
    plusSlides(1);
  });

});

@-webkit-keyframes fade {
  from {
    opacity: .4
  }
  to {
    opacity: 1
  }
}
@keyframes fade {
  from {
    opacity: .4
  }
  to {
    opacity: 1
  }
}
.slideshow-container {
  position: relative;
  margin: auto;
}
.prev,
.next {
  cursor: pointer;
  position: absolute;
  top: 0;
  top: 50%;
  width: auto;
  margin-top: -22px;
  padding: 16px;
  color: white;
  font-weight: bold;
  font-size: 18px;
  transition: 1.6s ease;
  border-radius: 0 3px 3px 0;
}
.next {
  right: 0;
  border-radius: 3px 0 0 3px;
}
.prev:hover,
.next:hover {
  background-color: rgba(0, 0, 0, 0.8);
}
.text {
  color: #f2f2f2;
  font-size: 15px;
  padding: 8px 12px;
  position: absolute;
  bottom: 8px;
  width: 100%;
  text-align: center;
}
.numbertext {
  color: #f2f2f2;
  font-size: 12px;
  padding: 8px 12px;
  position: absolute;
  top: 0;
}
.fade {
  -webkit-animation-name: fade;
  -webkit-animation-duration: 1.5s;
  animation-name: fade;
  animation-duration: 1.5s;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="slideshow-container">
  <div class="mySlides fade">
    <div class="numbertext">1 / 3</div>
    <img class="img-responsive" src="pic1.jpg" alt='Entrada'>
    <div class="text">1</div>
  </div>

  <div class="mySlides fade">
    <div class="numbertext">2 / 3</div>
    <img class="img-responsive" src="pic2.jpg">
    <div class="text">2</div>
  </div>

  <div class="mySlides fade">
    <div class="numbertext">3 / 3</div>
    <img class="img-responsive" src="pic3.jpg">
    <div class="text">3</div>
  </div>

  <a class="prev">&#10094;</a>
  <a class="next">&#10095;</a>
</div>

页面加载正确，但图片在一秒钟左右后消失。

我该如何解决？

Answer 1

不久前我也遇到过同样的问题。我通过添加animation-fill-mode: forwards; 解决了它。

通常，动画会运行并停止，然后返回原始样式。

使用animation-fill-mode，您可以改变这种行为。 forwards 会在动画结束后保持动画的结果。

实现见 CSS sn-p 底部。

$(document).ready(function() {
  var slideIndex = 1;

  function showSlides(n) {
    var slides = $(".mySlides");
    var i;

    if (n > slides.length) {
      slideIndex = 1;
    }

    if (n < 1) {
      slideIndex = slides.length;
    }

    for (i = 0; i < slides.length; i++) {
      slides[i].style.display = "none";
    }

    slides[slideIndex - 1].style.display = "block";
  }

  function plusSlides(n) {
    showSlides(slideIndex += n);
  }

  showSlides(slideIndex);

  $(".prev").click(function() {
    plusSlides(-1);
  });

  $(".next").click(function() {
    plusSlides(1);
  });

});

@-webkit-keyframes fade {
  from {
    opacity: .4
  }
  to {
    opacity: 1
  }
}
@keyframes fade {
  from {
    opacity: .4
  }
  to {
    opacity: 1
  }
}
.slideshow-container {
  position: relative;
  margin: auto;
}
.prev,
.next {
  cursor: pointer;
  position: absolute;
  top: 0;
  top: 50%;
  width: auto;
  margin-top: -22px;
  padding: 16px;
  color: white;
  font-weight: bold;
  font-size: 18px;
  transition: 1.6s ease;
  border-radius: 0 3px 3px 0;
}
.next {
  right: 0;
  border-radius: 3px 0 0 3px;
}
.prev:hover,
.next:hover {
  background-color: rgba(0, 0, 0, 0.8);
}
.text {
  color: #f2f2f2;
  font-size: 15px;
  padding: 8px 12px;
  position: absolute;
  bottom: 8px;
  width: 100%;
  text-align: center;
}
.numbertext {
  color: #f2f2f2;
  font-size: 12px;
  padding: 8px 12px;
  position: absolute;
  top: 0;
}
.fade {
  -webkit-animation-name: fade;
  -webkit-animation-duration: 1.5s;
  -webkit-animation-fill-mode: forwards; 
  animation-name: fade;
  animation-duration: 1.5s;
  animation-fill-mode: forwards; 
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="slideshow-container">
  <div class="mySlides fade">
    <div class="numbertext">1 / 3</div>
    <img class="img-responsive" src="http://placehold.it/350x150" alt='Entrada'>
    <div class="text">1</div>
  </div>

  <div class="mySlides fade">
    <div class="numbertext">2 / 3</div>
    <img class="img-responsive" src="http://placehold.it/350x150">
    <div class="text">2</div>
  </div>

  <div class="mySlides fade">
    <div class="numbertext">3 / 3</div>
    <img class="img-responsive" src="http://placehold.it/350x150">
    <div class="text">3</div>
  </div>

  <a class="prev">&#10094;</a>
  <a class="next">&#10095;</a>
</div>