title: Animate the process of tab switching
body: <p>Anyone have a walk around on animating the process when switching tabs? </p>
  
  <p>I am currently doing this with 2 issues.</p>
  
  <p>1: It messes up my UIControl colors. 
  2: It switches the tab first, thereafter perform the animation.</p>
  
  <p>I want to implement something like the effect when pushing a view to navigation stack.</p>
  
  <pre><code>[UIView beginAnimations:nil context:NULL];
  [UIView setAnimationDuration:1.0];
  [UIView setAnimationTransition:UIViewAnimationTransitionCurlUp forView:bookingVC.view cache:YES];
  [UIView commitAnimations];
  [self.tabBarController setSelectedIndex:0];
  </code></pre>
  
  <p>Right now I am doing this, which doesn't have any animation effect.</p>
  
  <pre><code>NSArray *tabBarVC = [self.tabBarController viewControllers];
  UINavigationController *firstTabNC = [tabBarVC objectAtIndex:0];
  BookingViewController *bookingVC = (BookingViewController *)[[firstTabNC viewControllers] objectAtIndex:0];
  [bookingVC setNSStringProperty:newString]; //this string will be displayed on a UITextField whenever viewDidAppear; 
  
  // So, I need some animation here when I switch tabs to make it more obvious that the UITextField is updated.
  [self.tabBarController setSelectedIndex:0];
  </code></pre>
  
  <p>I am totally clueless on creating my own animation, please do guide me along. I am opened to ideas to better the presentation.
  Thanks.</p>