title: UICollectionView & custom UICollectionReusableView not works
body: <p>I'm trying to use custom <code>UICollectionReusableView</code> (which has own class and XIB) in my <code>UICollectionView</code> header. But after fetching data in the place of header I have nothing.</p>
  
  <p>My steps:</p>
  
  <ol>
  <li><p>Registering class in <strong>viewDidLoad</strong>:  </p>
  
  <pre><code> [self.collectionView registerClass:[CollectionViewHeader class] 
    forSupplementaryViewOfKind: UICollectionElementKindSectionHeader 
    withReuseIdentifier:@"HeaderView"];
  </code></pre></li>
  <li><p>Trying to show:</p>
  
  <pre><code>- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
  {
  UICollectionReusableView *reusableView = nil;
  
  if (kind == UICollectionElementKindSectionHeader) {
      CollectionViewHeader *collectionHeader = [self.collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"HeaderView" forIndexPath:indexPath];
  
      NSInteger section = [indexPath section];
      id &lt;NSFetchedResultsSectionInfo&gt; sectionInfo = [fetchRecipes sections][section];
      collectionHeader.headerLabel.text = @"bla-bla-bla";
  
      reusableView = collectionHeader;
  }
  
  return reusableView;
  }
  </code></pre></li>
  </ol>
  
  <p>Can anybody tell me what's wrong? ) 
  Thanks for any advice</p>