title: UITableView - implementing index
body: <p>I want to implement an index that is being displayed at the right side of a table. I've found out how to display it.
  How can I scroll to a certain position in my table, after a certain index item was pressed?</p>
  
  <p>In the index I am not displaying all the alphabet, but in the following manner:</p>
  
  <pre><code>#define ALPHA_ARRAY= @"A●D●G●J●M●P●S●V●Z"
  </code></pre>
  
  <p>So when the user presses between A and D I want to go to items starting from A and so on. .</p>
  
  <p>How can I implement it?</p>
  
  <p>I want to make something similar to the index available in the contacts application on iPhone.</p>