title: Using the MIDI tick position to control movement of a graphic marker in a sequence
body: <p>I'm trying to assemble a graphical representation of a MIDI sequence, and I'd like a vertical line to move across the panel horizontally as the sequence plays, reflecting the actual position in the sequence.  I know that I should use something like <code>getTickPosition()</code> to provide the location of the vertical line.  </p>
  
  <p>But how do I fire off these events so that the vertical line knows to redraw itself?  Do I create a special listener that the ticks somehow trigger?</p>