title: Why UICollectionView didSelect method does not work?
body: <p>I've created my <code>UICollectionView</code> programmatically and in this case my <code>didSelectItemAtIndexPath</code> method does not call at all.</p>
  
  <pre><code>let collectionView = UICollectionView(frame: CGRect(x: 0, y: 0, width: CGRectGetWidth(self.view.frame), height: 360), collectionViewLayout: layout)
  collectionView.delegate = self
  collectionView.dataSource = self
  collectionView.userInteractionEnabled = true
  </code></pre>
  
  <p>So, what is a problem? Why when I tap on the cells I do not get my response?</p>
  
  <pre><code>func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
      print("Selected Cell: \(indexPath.row)")
  }
  </code></pre>