title: Save value of dropdown categories lists in Visual Composer (WPBakery)
body: <p>I'm stuck on a problem and don't know how to solve it.</p>
  
  <p>This is my code </p>
  
  <pre><code>$categories_array = array( __( 'All Categories', 'js_composer' ) =&gt; 'mp-all-categories' );
  $category_list = get_terms( 'download_category', array( 'hide_empty' =&gt; false ) );
  
      if ( is_array( $category_list ) &amp;&amp; ! empty( $category_list ) ) {
          foreach ( $category_list as $category_details ) {   
              $begin = __(' (ID: ', 'js_composer');
              $end = __(')', 'js_composer');
              $categories_array[ $category_details-&gt;name . $begin. $category_details-&gt;term_id . $end ] = $category_details-&gt;term_id;  
          }
      }
  
  
   vc_map( array(
     ...
     "params" =&gt; array(    
      array(
          'type' =&gt; 'dropdown',
          'heading' =&gt; __( 'Select Category', 'js_composer' ),
          'param_name' =&gt; 'mp_category',
          'value' =&gt; $categories_array,           
          'description' =&gt; __( 'Select a category', 'js_composer' ),
      ),  
  </code></pre>
  
  <p>And this is the code I'm having problems with</p>
  
  <pre><code>if( $categories_array != 'mp-all-categories' ) {
          $args['tax_query'][] = array(
              'taxonomy'           =&gt; 'download_category',
              'field'              =&gt; 'term_id',
              'terms'              =&gt; $categories_array
              //'terms'            =&gt; '23',
  
          );
  </code></pre>
  
  <p>The <code>$categories_array</code> doesn't seem to work.</p>
  
  <p>When I select a category from the list, no posts show up while I know there are posts inside the category. Anyone an idea what I'm doing wrong?</p>