title: How can I disable/enable UISearchBar keyboard's Search button?
body: <p>I am using <code>UISearchBar</code> in my code. I have imported its delegate in header file and implemented some delegate methods in implementation file also.</p>
  
  <p>When we tap on the <code>UISearchBar</code>, a keyboard will appear to enter text. The return key of the keyboard is "<em>Search</em>" button. It will disabled by default. When we enter a character, It will get enabled. (Am I right?) </p>
  
  <p>Here the problem comes.. I want to enable the <code>UISearchBar</code> keyboard's return key when the user types atleast two letters. </p>
  
  <p>Is it possible? If yes, how can we do it?</p>
  
  <p>Thanks</p>