title: UICollectionViewCell change background color
body: <p>I have <code>UICollectionview</code> with sections and two cell class. </p>
  
  <pre><code>- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
  {
  
  myCell *cell;
  
      firstDayInMonth = [self dayWeekStart:[self getDateFromItem:dateFromStart section:indexPath.section row:1]];
  
      if (indexPath.row &lt; firstDayInMonth) {
          cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"cellCalendarEmpty" forIndexPath:indexPath];
      } else {
          cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"cellCalendar" forIndexPath:indexPath];
      }
  }
  </code></pre>
  
  <p>I have start item, section and period. Beginning from the start section and item i need to change background color cell depending on period. i need to change only <code>cellCalendar</code>. I use <code>cellCalendarEmpty</code> to move first <code>cellCalendar</code>.</p>