title: ios - view is not rendered until button is clicked
body: <p>I am developing a small ios app and I am struggling with a strange problem.
  I have a view, in the view I have a button and a few images.
  The images are loaded in an asynchronous manner. 
  The view is hidden and is not initially part of the ViewController.</p>
  
  <p>When a user clicks a button, I instantiate the view and add it as a subview.
  When the subview is added, only some of the images are rendered (usually the first two, out of 25). When I click any button on the view though, all of a sudden all the other images appear.</p>
  
  <p>What could cause this issue? Why do the images render only when I click a button? (the button has no code in its event handler). </p>
  
  <p>Applying a timeout fixes this issue. I don't understand why though:</p>
  
  <pre><code>-(void) viewDidAppear:(BOOL)animated
  {
      [super viewDidAppear:animated];
      [NSThread sleepForTimeInterval:0.1];
  }
  </code></pre>
  
  <p>I've tried supplying a code sample, but I can't seem to minimize it to a trivial example.</p>