title: removefromsuperview and addsubview not changing display
body: <p>I'm pretty new to iOS development, and I'm trying to develop a simple app in which a button changes the subviews. I have a base <code>RootViewController</code>, which displays <code>MiddleView</code> correctly on <code>init</code>. <code>MiddleView</code> has a single button, labeled "First," which is connected (in Interface Builder) to <code>RootViewController</code>'s <code>-openFirstView</code>.</p>
  
  <p>Here's how <code>MiddleView</code> is displayed within <code>RootViewController</code>'s <code>-viewDidLoad</code></p>
  
  <pre><code>MiddleViewController *middleTemp = [[MiddleViewController alloc] initWithNibName:@"MiddleView" bundle:nil];
      self.middle = middleTemp;
      self.middle.rootViewController = self;
      [self.view addSubview:middle.view];
      [middleTemp release];
  </code></pre>
  
  <p>So I have the following <code>ViewControllers</code>s: <code>MiddleViewController</code> and <code>FirstController</code> which control <code>MiddleView</code> and <code>FirstView</code> respectively, and a <code>RootViewController</code> which switches between the two.</p>
  
  <p>I've linked this by placing a <code>RootViewController</code> reference in <code>MiddleViewController</code>, and adding </p>
  
  <pre><code>self.middle.rootViewController = self; 
  </code></pre>
  
  <p>to <code>RootViewController</code>'s <code>-viewDidLoad</code>.</p>
  
  <pre><code>-(IBAction)openFirstView:(id)sender{
      [middle.view removeFromSuperview];
      [self.view addSubview:firstController.view];
  }
  </code></pre>
  
  <p>Note: I've tried initializing firstController within <code>-openFirstView</code>, and when it initially didn't run, I moved the initialization to <code>-viewDidLoad</code> and have proven that it is initializing from the nib correctly by displaying FirstView directly in <code>-viewDidLoad</code></p>
  
  <p>Where <code>firstController</code> is loaded to a reference earlier in code. However, when I run the code and click the button, nothing in the view changes. </p>
  
  <p>I've done some more diagnosing. I've found specifically that <code>-ViewDidLoad</code> in <code>rootViewController</code> is being called twice, once on the original load and once on the first click of the button, and I'm not sure exactly why.</p>