title: Objective-C NSTimer update label doesn't update
body: <p>I have two methods below. One method (<code>timerHit</code>) which gets the track duration of the current playing song, minuses 1 from it and prints it out in the log it then also updates a label with the value too. The other method (<code>countDown</code>) which repeats every second calls the <code>timerHit</code> method, however it doesn't seem to work correctly the <code>NSLog</code> statement works and repeats thus printing the value every second but the update label statement <code>[duration setDoubleValue:trackDuration];</code> doesn't work. Can anyone help me?</p>
  
  <pre><code>- (void)countDown {
      [NSTimer scheduledTimerWithTimeInterval:1.0f target:self selector:@selector(timerHit:) userInfo:nil repeats:YES];
  }
  
  - (void)timerHit:(NSTimer *)p_timer
  {
      iTunesApplication *iTunes = [SBApplication applicationWithBundleIdentifier:@"com.apple.iTunes"];
      double trackDuration = [[iTunes currentTrack] duration];
      if( trackDuration &lt;= 1 &amp;&amp; [p_timer isValid] )
          [p_timer invalidate];
      trackDuration--;
      NSLog(@"%d", trackDuration);
      [duration setDoubleValue:trackDuration];
  }
  </code></pre>
  
  <p>Thanks, Sami.</p>