title: Hide items in a listview
body: <p>I have tried to hide items in a custom list adapter. I can hide the visibility of the text but I cannot hide the whole list item. It still shows the dividers etc. I have tried:     </p>
  
  <pre><code>tv.setVisibility(View.INVISIBLE);
  tv.setVisibility(View.GONE);
  convertView.setVisibility(View.INVISIBLE);
  convertView.setVisibility(View.GONE);
  </code></pre>
  
  <p>When I use the convertView i get a null pointer exception. </p>