title: iOS - UIScrollView doesn't update its content and some UIViews disappear after reload
body: <p>I have <code>UITableViewController</code> with <code>UIScrollView</code> inside <code>UIView</code> as its header. 
  <code>UIScrollView</code> is used to display slideshow of images:</p>
  
  <pre><code>UITableView
   -UITableViewHeaderView
     -UIView
        -UIScrollView
          -UIImageView
            ...
        -UIPageControl
  </code></pre>
  
  <p>Every image has a subview with its title and description:</p>
  
  <pre><code>UIImageView
    -UIView
      -UILabel
      -UILabel
  </code></pre>
  
  <p>When I need to update my <code>tableView</code> a delegate method is called which reloads data in a <code>tableView</code> and calls <code>addImages</code> method:</p>
  
  <pre><code>- (void)eventsUpdated
  {
      if ([self respondsToSelector:@selector(setRefreshControl:)])
          [self.refreshControl endRefreshing];
  
      [self.tableView reloadData];
      [self addImages];
  }
  </code></pre>
  
  <p>Here is how I add my images:</p>
  
  <pre><code>- (void)addImages
  [self.scrollView.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
  
      for (int i = 0; i &lt; images.count; i++) {
          CGRect frame;
          frame.origin.x = self.scrollView.frame.size.width * i;
          frame.origin.y = 0;
          frame.size = self.scrollView.frame.size;
  
          UIImageView *subview = [self createImageViewForEvent:[images objectAtIndex:i] inFrame:frame];
          subview.frame = frame;
          [self.scrollView addSubview:subview];
      }
  
      self.scrollView.contentSize = CGSizeMake(scrollView.frame.size.width*images.count, scrollView.frame.size.height);
      pageControll.currentPage = 0;
      pageControll.numberOfPages = images.count;
  
  }
  
  - (UIImageView *)createImageViewForEvent:(Event *)event inFrame:(CGRect)frame
  {
      UIImage *image;
  
      NSString *imageName = [event.imageName lastPathComponent];
      NSString *bundleFilePath = [[NSBundle mainBundle] pathForResource:[imageName stringByDeletingPathExtension] ofType:[imageName pathExtension]];
  
      image = [UIImage imageWithContentsOfFile:bundleFilePath];
  
  
      UIImageView *output = [[UIImageView alloc] initWithImage:image];
      output.frame = frame;
  
      UIView *descriptionView = [[UIView alloc] initWithFrame:CGRectMake(0, frame.size.height*0.7, frame.size.width, frame.size.height*0.3)];
  
      descriptionView.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.5];
      descriptionView.alpha = 1.0;
  
      UILabel *header = [[UILabel alloc] initWithFrame:CGRectMake(10, 5, frame.size.width-20, 12)];
      header.textColor = [UIColor colorWithRed:210/256.0 green:217/256.0 blue:231/256.0 alpha:1.0];
      header.font = [UIFont fontWithName:@"Helvetica" size:17];
      header.backgroundColor = [UIColor clearColor];
      header.lineBreakMode = UILineBreakModeTailTruncation;
      header.numberOfLines = 1;
  
      UILabel *description = [[UILabel alloc] initWithFrame:CGRectMake(10, 22, frame.size.width-20, 28)];
      description.textColor = [UIColor colorWithRed:255/256.0 green:255/256.0 blue:255/256.0 alpha:1.0];
      description.font = [UIFont fontWithName:@"Helvetica" size:12];
      description.backgroundColor = [UIColor clearColor];
      description.lineBreakMode = UILineBreakModeTailTruncation;
      description.numberOfLines = 2;
  
      header.text = event.title;
      [descriptionView addSubview:header];
  
      description.text = event.shortDesription;
      [descriptionView addSubview:description];
  
      [output addSubview:descriptionView];
  
      return output;
  }
  </code></pre>
  
  <p>After first launch everything works fine, but if I try to reload my <code>tableView</code> and call <code>addImages</code> again, all UILabels disappear, only <code>UIImageView</code> and <code>UIView</code> are visible.</p>
  
  <p><strong>UPD:</strong></p>
  
  <p>What I have noticed, is that my UILabels appear after some time, approximately after 30 seconds. I have never experienced something similar before</p>
  
  <p><strong>UPD 2:</strong></p>
  
  <p>After I reload my <code>tableView</code> and <code>scrollview</code>, <code>scrollView's</code> content is not updated right away, only after I start scrolling</p>