title: UISeachBar detect when user press Search button
body: <p>I try to get notification when the <code>Search</code> button is clicked in the keyboard in the <code>UISearchBar</code> with this :</p>
  
  <pre><code>    - (BOOL)textFieldShouldReturn:(UITextField *)textField{
  
          return YES;
      }
  </code></pre>
  
  <p>But this method won't call when I press the Search button.</p>