title: Conditionally show items of Nav widget
body: <p>I want to add a condition to menu items so when a user logs in, he will see menu depending on his <code>user_type</code>. Here is my code.</p>
  
  <pre><code>Nav::widget([
      'encodeLabels' =&gt; false,
      'options' =&gt; ['class' =&gt; 'sidebar-menu'],
      'items' =&gt; [
      // I want to insert condition here
      [
          'label' =&gt; '&lt;span class="fa fa-fw fa-globe"&gt;&lt;/span&gt; Menu1',
          'url' =&gt; ['/menu1'],
      ],
      [
          'label' =&gt; '&lt;span class="fa fa-fw fa-list-alt"&gt;&lt;/span&gt; Menu2',
          'url' =&gt; ['/menu2'],
      ],
  ]);
  </code></pre>
  
  <p>Some users can access the <code>menu1</code> and others can access only the <code>menu2</code>.</p>