这是一款炫酷的jQuery和css3弹性3d图片翻转分组展示特效。内容分组过滤对于一些网站来说是非常重要的,如商务网站和图片站。如何使组图片切换时不必刷新网页呢?最好的方法是使用CSS3 3D Transforms来在用户选择某组类别时翻转图片。这款插件在IE9以下的IE浏览器中看不到效果。

HTML

html结构使用一个nav作为wrapper,在里面使用无序列表作为分组图片。在插件中只用三个分组,但是你会发现使用了4个列表项,第一个列表项是一个占位,它将被用来在移动设备上制作选择按钮(通过jQuery)。在大屏幕上这个占位将被移除(display:none)。

<nav>
    <ul>
        <li class="placeholder"> 
            <a href="#0">Option 1</a> <!-- default option on mobile -->
        </li> 
 
        <li>
            <a href="#0">Option 1</a>
        </li>
 
        <li>
            <a href="#0">Option 2</a>
        </li>
 
        <li>
            <a href="#0">Option 3</a>
        </li>
    </ul>
</nav>
                

在每个分组中,又使用一个无序列表来作为图片画廊。这个无序列表的ul元素将被用于旋转,它里面的li元素将和它一起呗旋转。

<ul>
    <li>
        <ul> <!-- this is the element that will rotate -->
            <li>
                <img src="img/thumb-1.jpg" alt="thumbnail">
            </li>
            <li>
                <img src="img/thumb-2.jpg" alt="thumbnail">
            </li>
            <li>
                <img src="img/thumb-3.jpg" alt="thumbnail">
            </li>
        </ul>
    </li>
    <li>
        <ul> <!-- this is the element that will rotate -->
            <li>
                <img src="img/thumb-1.jpg" alt="thumbnail">
            </li>
            <li>
                <img src="img/thumb-2.jpg" alt="thumbnail">
            </li>
            <li>
                <img src="img/thumb-3.jpg" alt="thumbnail">
            </li>
        </ul>
    </li>
    <!-- ... -->
</ul>
                

CSS

包含图片的无序列表的第一个列表项是可见的,我们给它class.is-visible

li.is-visible { /* the front item, visible by default */
  position: relative;
  z-index: 5;
}
                

在同一个无序列表中,将使用绝对定位,这意味着其他列表项的高度将依赖与第一个列表项的高度。

另外两个class是 .is-hidden .is-selected .is-hidden 将隐藏所有的列表项。 .is-selected 将使被选择的分组被显示。注意:这里使用CSS3 transformation(180deg rotation)来旋转ul元素。

li.is-hidden { /* the hidden items, right behind the front one */
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  width: 100%;
  z-index: 1;
  transform: rotateY(180deg); 
}
 
li.is-selected { /* the next item that will be visible */
  z-index: 3 !important;
}
                

当用户点击分组按钮时,我们使用jQuery为ul添加.is-switched来使它旋转。

ul.is-switched li.is-visible {
  transform: rotateY(180deg);
  animation: cd-rotate 0.5s;
}
 
ul.is-switched li.is-hidden {
  transform: rotateY(0);
  animation: cd-rotate-inverse 0.5s;
  opacity: 0;
}
 
ul.is-switched li.is-selected {
  opacity: 1;
}
                

我们使用 CSS3 Animations 来制作弹性效果,这不会影响到CSS3 transitions的旋转效果。

@keyframes cd-rotate {
  0% {
    transform: perspective(800px) rotateY(0);
  }
 
  70% { /* this creates the bounce effect */
    transform: perspective(800px) rotateY(200deg);
  }
 
  100% {
    transform: perspective(800px) rotateY(180deg);
  }
}
 
@keyframes cd-rotate-inverse {
  0% {
    transform: perspective(800px) rotateY(-180deg);
  }
 
  70% {
    transform: perspective(800px) rotateY(20deg);
  }
 
  100% {
    transform: perspective(800px) rotateY(0);
  }
}
                

你也许会有些奇怪:为什么不直接将旋转应用到ul元素上?因为那样做需要使用到transform-style: preserve-3d。看起来这样做更简单,但是别忘记了,IE11以下的浏览器不支持transform-style: preserve-3d

JAVASCRIPT

jQuery(document).ready(function($){
  //wrap each one of your filter in a .cd-gallery-container
  bouncy_filter($('.cd-gallery-container'));

  function bouncy_filter($container) {
    $container.each(function(){
      var $this = $(this);
      var filter_list_container = $this.children('.cd-filter'),
        filter_values = filter_list_container.find('li:not(.placeholder) a'),
        filter_list_placeholder = filter_list_container.find('.placeholder a'),
        filter_list_placeholder_text = filter_list_placeholder.text(), 
        filter_list_placeholder_default_value = 'Select',
        gallery_item_wrapper = $this.children('.cd-gallery').find('.cd-item-wrapper');

      //store gallery items
      var gallery_elements = {};
      filter_values.each(function(){
        var filter_type = $(this).data('type');
        gallery_elements[filter_type] = gallery_item_wrapper.find('li[data-type="'+filter_type+'"]');
      });

      //detect click event
      filter_list_container.on('click', function(event){
        event.preventDefault();
        //detect which filter item was selected
        var selected_filter = $(event.target).data('type');
          
        //check if user has clicked the placeholder item (for mobile version)
        if( $(event.target).is(filter_list_placeholder) || $(event.target).is(filter_list_container) ) {

          (filter_list_placeholder_default_value == filter_list_placeholder.text()) ? filter_list_placeholder.text(filter_list_placeholder_text) : filter_list_placeholder.text(filter_list_placeholder_default_value) ;
          filter_list_container.toggleClass('is-open');

        //check if user has clicked a filter already selected 
        } else if( filter_list_placeholder.data('type') == selected_filter ) {
          
          filter_list_placeholder.text($(event.target).text()) ;
          filter_list_container.removeClass('is-open'); 

        } else {
          //close the dropdown (mobile version) and change placeholder text/data-type value
          filter_list_container.removeClass('is-open');
          filter_list_placeholder.text($(event.target).text()).data('type', selected_filter);
          filter_list_placeholder_text = $(event.target).text();
          
          //add class selected to the selected filter item
          filter_values.removeClass('selected');
          $(event.target).addClass('selected');

          //give higher z-index to the gallery items selected by the filter
          show_selected_items(gallery_elements[selected_filter]);

          //rotate each item-wrapper of the gallery
          //at the end of the animation hide the not-selected items in the gallery amd rotate back the item-wrappers
          
          // fallback added for IE9
          var is_explorer_9 = navigator.userAgent.indexOf('MSIE 9') > -1;
          
          if( is_explorer_9 ) {
            hide_not_selected_items(gallery_elements, selected_filter);
            gallery_item_wrapper.removeClass('is-switched');
          } else {
            gallery_item_wrapper.addClass('is-switched').eq(0).one('webkitAnimationEnd oanimationend msAnimationEnd animationend', function() {   
              hide_not_selected_items(gallery_elements, selected_filter);
              gallery_item_wrapper.removeClass('is-switched');
            });
          }
        }
      });
    });
  }
});

function show_selected_items(selected_elements) {
  selected_elements.addClass('is-selected');
}

function hide_not_selected_items(gallery_containers, filter) {
  $.each(gallery_containers, function(key, value){
      if ( key != filter ) {  
      $(this).removeClass('is-visible is-selected').addClass('is-hidden');

    } else {
      $(this).addClass('is-visible').removeClass('is-hidden is-selected');
    }
  });
}