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+---
+title: Category columns
+layout: demo
+category: demos
+related: layouts
+---
+
+<section id="copy">
+  <p>This demo uses a custom layout mode that arranges elements into columns based on an attribute.</p>
+</section>
+
+<section id="options" class="clearfix">
+
+  <h3>Filters</h3>
+
+  <ul id="filters" class="option-set floated clearfix">
+    <li><a href="#show-all" class="selected">show all</a></li>
+    <li><a href="#metalloid">metalloid</a></li>
+    <li><a href="#metal">metal</a></li>
+    <li><a href="#alkali">alkali</a></li>
+    <li><a href="#alkaline-earth">alkaline-earth</a></li>
+    <li><a href="#inner-transition">inner-transition</a></li>
+    <li><a href="#lanthanoid">lanthanoid</a></li>
+    <li><a href="#actinoid">actinoid</a></li>
+    <li><a href="#transition">transition</a></li>
+    <li><a href="#post-transition">post-transition</a></li>
+    <li><a href="#nonmetal">nonmetal</a></li>
+    <li><a href="#other">other</a></li>
+    <li><a href="#halogen">halogen</a></li>
+    <li><a href="#noble-gas">noble-gas</a></li>
+  </ul>
+
+  <h3>Etc</h3>
+
+  <ul id="etc" class="floated clearfix">
+    <li id="insert"><a href="#insert">Insert new elements</a></li>
+    <li id="append"><a href='#append'>Append new elements</a></li>
+  </ul>
+</section> <!-- #options -->
+
+<div id="container" class="clearfix">
+  {% for elem_number in site.random_order | limit:60 %}
+    {% assign element = site.elements[elem_number] %}
+    {% include element-partial.html %}
+  {% endfor %}
+</div>
+
+{% include footer.html %}
+
+<script src="../{{ site.jquery_js }}"></script>
+<script src="../{{ site.isotope_js }}"></script>
+<script src="../js/fake-element.js"></script>
+<script>
+
+  // categoryRows custom layout mode
+  $.extend( $.Isotope.prototype, {
+  
+    _categoryRowsReset : function() {
+      // reset namespace properties
+      this.categoryRows = {
+        // the number of rows
+        rows : 0,
+        // the x & y position in each row
+        positions : {}
+      };
+    
+      return this;
+    },
+  
+    _categoryRowsLayout : function( $elems ) {
+      var instance = this;
+          options = this.options.categoryRows,
+          // namespaced properties
+          props = this.categoryRows;
+      $elems.each(function(){
+        var $this = $(this),
+            // get row based on function passed in options
+            rowName = options.getRow( $this );
+      
+        if ( !props.positions[ rowName ] ) {
+          // if row does not exists, create it
+          props.positions[ rowName ] = {
+            x : instance.posLeft,
+            y : instance.posTop + options.rowHeight * props.rows
+          };
+          // increment rows
+          props.rows ++;
+        }
+      
+        instance._pushPosition( $this, props.positions[ rowName ].x, props.positions[ rowName ].y );
+      
+        props.positions[ rowName ].x += $this.outerWidth(true);
+      
+      });
+    
+      return this;
+    },
+  
+    _categoryRowsGetContainerSize : function() {
+      var y = this.categoryRows.rows * this.options.categoryRows.rowHeight + this.posTop,
+          maxX = 0,
+          rowName, position;
+    
+      // get max X position from the positions object
+      for ( rowName in this.categoryRows.positions ) {
+        position = this.categoryRows.positions[ rowName ]
+        maxX = position.x > maxX ? position.x : maxX;
+      }
+      return { width: maxX, height: y };
+    },
+  
+    _categoryRowsResize : function() {
+      return this;
+    }
+  
+  });
+  
+  var $container = $('#container');
+
+  $('#filters').find('a').click(function(){
+    // get href attribute, minus the #, plus a . to make it a class
+    var filterName = '.' + $(this).attr('href').slice(1);
+    filterName = filterName === '.show-all' ? '*' : filterName;
+    $container.isotope({ filter: filterName })
+    return false;
+  });
+
+  {% include add-buttons.js %}
+
+  {% include option-buttons.js %}
+  
+
+  $(function(){
+
+    $container.isotope({
+      itemSelector : '.element',
+      layoutMode : 'categoryRows',
+      categoryRows : {
+        rowHeight : 120,
+        getRow : function( $elem ) {
+          return $elem.attr('data-category');
+        }
+      },
+      animationEngine : $.browser.opera ? 'jquery' : 'best-available'
+    });
+
+
+  });
+</script>
+  
+  
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