title: Countdown Timer
body: <p>I'm trying to create a countdown timer that takes countdown, an IBOutlet connected to a textfield, from 60 seconds down to 0.  I'm not sure </p>
  
  <p>A. How to limit the repeats to 60 and </p>
  
  <p>B. How to decrement the countdown in advanceTimer:</p>
  
  <pre><code>- (IBAction)startCountdown:(id)sender
  {
      NSTimer *countdownTimer = [NSTimer scheduledTimerWithTimeInterval:1 target:self     selector:@selector(advanceTimer:) userInfo:nil repeats:YES];
      NSRunLoop *runLoop = [NSRunLoop currentRunLoop];
      [runLoop addTimer:countdownTimer forMode:NSDefaultRunLoopMode];
  }
  
  - (void)advanceTimer:(NSTimer *)timer
  {
      [countdown setIntegerValue:59];
  }
  </code></pre>