title: Close the keyboard on UITextField
body: <p>I'm a newbie developing for iOS devices. I inserted an UITextField on InterfaceBuilder, and I assigned with the code: <pre><code>
  @interface ComposeViewController : UIViewController {
   id &lt;ComposeViewControllerDelegate> delegate;
   IBOutlet UITextField *notificationTitle;
  }
  </code></pre>
  How I could allow to close the keyboard when the user press the "Return" key?</p>