title: Null Pointer Exception on Custom ListView Item
body: <p>Ok so:
  I have a ListView with custom adapter. In ListView Item I have a SeekBar.
  ListView adapter is in different class, and I want to when I click on listview to play some sound and show it on SeekBar(Like a progress bar).</p>
  
  <p>The Problem:
  I get null pointer exception because the SeekBar is in different Layout. The Listview item Layout.</p>
  
  <p>Question:
  How can I or what I need to do to <em>link</em> SeekBar with Main Activity? </p>
  
  <p>I didn't add any code because it's pretty simple adapter I need an idea to do this. </p>