title: Android countdown timer gradually losing time
body: <p>I'm trying to create a countdown timer optimised for tablets, and it runs fine except for the slight detail that it gradually loses time, over time: over 5 mins it loses probably 1-2 seconds, when testing on my Xoom.</p>
  
  <p>Here is my onTick code:</p>
  
  <pre><code>        public void onTick(long millisUntilFinished) {
          // TODO Auto-generated method stub
          currentTime = System.currentTimeMillis();
          currentCount = startTime - currentTime;
          //currentCount = millisUntilFinished;
          displayCorrectTime();
      }
  </code></pre>
  
  <p>Initially I started with just using the 'millisUntilFinished', when I noticed the time was slipping. I then read around and tried to get it to sync up better by using the difference between the start time and 'now' to inform the timer. Unfortunately, both methods seem to lose time (I don't really understand how this second method can lose time, but nevertheless).</p>
  
  <p>Any suggestions?</p>