响应式图像缩略图答案

【问题标题】：Responsive Image Thumbnails响应式图像缩略图
【发布时间】：2018-05-02 22:15:20
【问题描述】：

我有一个带有缩略图的图像/视频轮播。我正在尝试使缩略图具有响应性，但我只能将宽度作为百分比而不是高度。每当我调整窗口大小时，它们都会失去我想要的矩形形状。

我尝试使用vh，但没有成功。我希望缩略图模仿我为 this site 所做的事情。

$(document).ready(function(){
  // get all images loaded
  var images = $(".chair-class");
  // thumbnails containers
  var thumbnailContainer = $("#thumbnails");
  var iframe1 = $('#sketchfab-iframe-1')[0];
  var iframe2 = $('#sketchfab-iframe-2')[0];
  var player1 = $f(iframe1);
  var player2 = $f(iframe2);
  // generate thumbnail images
  generateThumbnails(images, thumbnailContainer);
  // listeners for controls arrows
  $(".prev-next-button").on("click", function() {
    player1.api('pause');
    player2.api('pause');
    // get the images
    var currentImageIndex = images.index($(".chair-class[data-active=true]"));
    var isPrevious = $(this).hasClass("previous");
    var nextIndex;
    if (isPrevious) {
      if (currentImageIndex === 0) {
        nextIndex = images.length - 1;
      }

      if (currentImageIndex > 0) {
        nextIndex = currentImageIndex - 1;
      }
    } else {
      if (currentImageIndex === images.length - 1) {
        nextIndex = 0;
      }

      if (currentImageIndex < images.length - 1) {
        nextIndex = currentImageIndex + 1;
      }
    }

    // remove any active class from images
    images.removeClass("active").attr('data-active', "false");
    // get the next active image and add active class to that next current image
    var $nextImage = $(images[nextIndex]);
    var iframeId = $nextImage.data('iframe');
    if (iframeId) {
      $(images[nextIndex]).attr('data-active', "true");
      $('.sketchfab-iframe').removeClass('active');
      $('#' + iframeId).addClass('active');
    } else {
      $(images[nextIndex]).addClass("active").attr('data-active', "true");
      $('.sketchfab-iframe').removeClass('active');
    }
  });

  $(".thumb").on("click", function(event){
    event.preventDefault();
    var images = $(".chair-class");
    var indexSelected = $(this).data("img-index");
    var currentShown = images.index($(".chair-class[data-active=true]"));
    if (currentShown === indexSelected) return false;
    player1.api('pause');
    player2.api('pause');
    images.removeClass("active").attr('data-active', "false");
    var iframeId = $(this).data('iframe');
    if (iframeId) {
      $(images[indexSelected]).attr('data-active', "true");
      $('.sketchfab-iframe').removeClass('active');
      $('#' + iframeId).addClass('active');
    } else {
      images.removeClass("active");
      $(images[indexSelected]).addClass('active').attr('data-active', "true");;
      $('.sketchfab-iframe').removeClass('active');
    }
  });

  function generateThumbnails(images, container) {
    var ul = $("<ul>");
    images.each(function(index, element){
      var currentThumb = $("<img>");
      var li = $("<li>");
      var src = $(this).attr("src");
      currentThumb.attr("src", src);
      currentThumb.attr("class", "thumb");
      currentThumb.data("img-index", index);
      var iframe = $(this).data('iframe');
      if (iframe) {
        currentThumb.data("iframe", iframe);
      }
      li.append(currentThumb);
      ul.append(li);
    });
    container.append(ul);
  }
});

 * {
  margin: 0;
  padding: 0;
}

body{
  margin: 0;
  padding:0;
  font-size: 100%;
}

/* #green-room {
  background: #333 !important;
} */

.slideshow-container {
  max-width: 1000px;
  position: relative;
  margin: auto;
}

#chair, .chair-class {
  position: absolute;
  width: 100%;
  height: auto;
  max-width: 600px;
  max-height: 400px;
  margin: 0 auto;
  display: block;
  top: 0;
  left: 0;
  opacity: 0;
  transition: opacity .5s;
}

.chair-class.active {
  position: relative;
  opacity: 1;
}

#prev {
  position: absolute;
  color: black;
  left: 0;
  top: 0;
  bottom: 0;
}

#next {
  position: absolute;
  color: black;
  right: 0;
  top: 0;
  bottom: 0;
}

#prev p, 
#next p
{
  font-size: 3em;
}


#imgDetail {
  position: relative;
  width: 90%;
  margin: 0 auto;
  overflow: hidden;
}

#imgDetail a {
  text-decoration: none;
  display: flex;
  padding: 3% ;
  justify-content: center;
  align-items: center;
}

#imgDetail a:hover {
  background-color: #333;
  color: white;
  opacity: 0.5;
}

#imgDetail ul {
  margin: 0 auto;
  display: block;
}

#thumbnails {
  max-width: 1000px;
  width: 100%;
  display: inline-block;
  text-align: center;
}

.thumb { 
  width: 21%; 
/*   height: auto;  */
  height: 140px;
  
  margin-top: 15px;
  cursor: pointer;
}

#imgDetail li { 
  display: inline; 
}

#thumbnails ul{
  margin: 0 auto;
  display: block;
}

#thumbnails li{
  display: inline;
  padding-right: 2%;
}

#thumbnails li:last-child{
  padding-right: 0;
}

.sketchfab-iframe {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
}

.sketchfab-iframe {
  opacity: 0;
  margin: 0 auto;
  transition: opacity .5s;
  display: none;
}

.sketchfab-iframe.active {
  opacity: 1;
  position: relative;
  display: block;
}

<script src="https://f.vimeocdn.com/js/froogaloop2.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<!-- Images not Owned by Me -->

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Daniel Pollack</title>
    <link rel="stylesheet" type="text/css" href="css/styles.css"/>
    <script src="https://unpkg.com/scrollreveal/dist/scrollreveal.min.js">     </script>
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js">       </script>
    <script src="http://a.vimeocdn.com/js/froogaloop2.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/fitvids/1.2.0/jquery.fitvids.js">
  </script>
  </head>

  <body id="green-room">

    <div class="slideshow-container">
        <div id="imgDetail">
            <img data-iframe="sketchfab-iframe-1" src="https://i.vimeocdn.com/video/682901345_640.webp" class="chair-class" data-active="true" />
            <img data-iframe="sketchfab-iframe-2" src="https://i.vimeocdn.com/video/682890362_640.webp" class="chair-class" data-active="false" />
            <img src="http://www.davidwightman.net/_images_landscape/Behemot/Behemot_detail_3.jpg" class="chair-class" data-active="false" />

            <div class="aspect-ratio">
                <iframe id="sketchfab-iframe-1" class="sketchfab-iframe active" src="https://player.vimeo.com/video/255482396" width="80%" height="400" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
            </div>

            <div class="aspect-ratio">
                <iframe id="sketchfab-iframe-2" class="sketchfab-iframe" src="https://player.vimeo.com/video/255473875" width="80%" height="400" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
            </div>

            <!--CONTROLS-->
            <a href="javascript:void(0)" id="prev" class="prev-next-button previous">
                <p>&#10092;</p>
            </a>
            <a href="javascript:void(0)" id="next" class="prev-next-button next">
                <p>&#10093;</p>
            </a>
        </div>

        <!--Thumbnails-->
        <div id="thumbnails">
        </div>


</html>

【问题讨论】：

标签： javascript jquery html css

【解决方案1】：

过去，如果我想为在任何地方都可以使用的图像保持纵横比，我会将图像放置为 div 的背景，并在 div 内添加一个透明 png，即设置为比率。例如，如果我总是需要一个方形图像，我可以在其中放置一个 10 像素 X 10 像素的透明 PNG，并将其设置为 100% 宽。高度也将与宽度相同，并拉伸拥有它的 div（假设它的高度是自动的）。

对于 CSS，我会将 background-size 设置为 cover 或 auto，无论您需要什么。

【讨论】：

另外，我不喜欢仅仅推荐其他工具，但 Slick 过去曾为幻灯片创造了奇迹：kenwheeler.github.io/slick

【解决方案2】：

我会使用background-image而不是img标签，然后为背景设置一个固定比例的容器，如下所示：

div {
  width: 300px;
  height: 100px;
  resize: both;
  overflow: auto;
}

span {
  display: inline-block;
  width: 30%;
  height: 0;
  padding-top: calc(0.66 * 30%);
  background-image: url(https://dummyimage.com/300x200/000/fff);
  background-size: cover;

<div>
  <span></span>
  <span></span>
  <span></span>
</div>

填充是相对于容器的宽度设置的，甚至是padding-top 和padding-bottom，这使得创建固定宽高比的元素非常棒。

这样你的拇指将保持你想要的形状，即使在较低的屏幕宽度上。

【讨论】：

【解决方案3】：

我认为您最好的选择也是使用“背景大小”，并根据媒体查询更改“.thumb”高度。然后替换li.append(currentThumb); 和li.attr("class", "thumb").css('background-image', 'url(' + src + ')');

function generateThumbnails(images, container) {
        var ul = $("<ul>");
        images.each(function(index, element) {
            var currentThumb = $("<img>");
            var li = $("<li>");
            var src = $(this).attr("src");
            currentThumb.attr("src", src);
            currentThumb.attr("class", "thumb");
            currentThumb.data("img-index", index);

            var iframe = $(this).data('iframe');
            if (iframe) {
                currentThumb.data("iframe", iframe);
            }

            ul.append(li);
            li.attr("class", "thumb").css('background-image', 'url(' + src + ')');

        });
        container.append(ul);
    }

把css改成这个

.thumb { 
  width: 21%; 
  height: 140px;
  margin-top: 15px;
  cursor: pointer;
  background-size:cover;
}

#thumbnails li{
  display:inline-block;
  padding-right: 2%;
  margin:10px;
}

【讨论】：