title: Extjs 4.2: get value from the grid
body: <p>So let's say I have this grid</p>
  
  <p>id time</p>
  
  <p>1 10</p>
  
  <p>2 5</p>
  
  <p>3 10</p>
  
  <p>etc..</p>
  
  <p>How do I get the sum of the values under 'time'?</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>I tried to get the array of the value from the grid with this code</p>
  
  <pre><code>var sel2 = scope.getPlaylistDetailsGrid().data.items;
  </code></pre>
  
  <p>But it says: Uncaught TypeError: Cannot read property 'items' of undefined </p>