title: Problems calling instance method
body: <p>Following code changes tab name and select then index 2. </p>
  
  <pre><code>[(UITabBarItem*)[self.rootController.tabBar.items objectAtIndex:0] setTitle:@"User"];
  
  self.rootController.selectedIndex = 2;
  </code></pre>
  
  <p>However, it works for example when app didFinishLaunching method but not working when called like follows.</p>
  
  <p>touch up inside button triggers renameTabs:</p>
  
  <pre><code>- (IBAction) renameTabs: (id)sender
  {
      CompanyAppDelegate *theInstance = [[CompanyAppDelegate alloc] init];
      [theInstance rename];
  
  }
  </code></pre>
  
  <p>and in the controller:</p>
  
  <pre><code>- (void) rename
      {
  
          [(UITabBarItem*)[self.rootController.tabBar.items objectAtIndex:0] setTitle:@"User"];
  
          self.rootController.selectedIndex = 2;
  
      }
  </code></pre>
  
  <p>rename function is triggered and also defined at .h. No errors but nothing changes! Is there anything wrong?? Thank you</p>