title: Show Thumbnails in Backend Model Columns
body: <p>I'm using <a href="https://octobercms.com" rel="nofollow noreferrer">OctoberCMS</a> with Laravel.</p>
  
  <p>I use File Upload / Media Finder to attach an image. I'm trying to add thumbnails to the Backend Model columns.</p>
  
  <p>I tried following these guides:<br>
  <a href="https://octobercms.com/forum/post/how-to-display-pictures-in-backend-lists" rel="nofollow noreferrer">https://octobercms.com/forum/post/how-to-display-pictures-in-backend-lists</a><br>
  <a href="https://octobercms.com/docs/database/attachments" rel="nofollow noreferrer">https://octobercms.com/docs/database/attachments</a></p>
  
  <hr>
  
  <p><strong>File Upload</strong></p>
  
  <p><a href="https://i.stack.imgur.com/nmClE.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/nmClE.jpg" alt="file upload"></a></p>
  
  <hr>
  
  <p><strong>Columns Thumbnail</strong></p>
  
  <p><a href="https://i.stack.imgur.com/MnoWQ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MnoWQ.jpg" alt="photo"></a></p>
  
  <hr>
  
  <h2>Model</h2>
  
  <p>I have in my Model <code>Catalog.php</code></p>
  
  <pre><code>public $attachOne = [
      'photo' =&gt; 'System\Models\File'
  ];
  </code></pre>
  
  <hr>
  
  <p>In <code>columns.yamal</code></p>
  
  <p>Field <code>photo</code> set to <em>partial</em> and added <em>path</em>.</p>
  
  <hr>
  
  <p>In the partial <code>_photo.htm</code> I have</p>
  
  <pre><code>&lt;?php echo $this-&gt;photo-&gt;getThumb(100, 100, ['mode' =&gt; 'crop']); ?&gt;
  </code></pre>
  
  <hr>
  
  <h2>Error</h2>
  
  <p>I get <code>Error: Call to a member function getThumb() on null</code>.</p>
  
  <p>If I use <code>&lt;img src="" /&gt;</code> in the partial it will display an empty image in the columns, but I don't know what php to put as the src.</p>