title: Display a timer for an iOS app that persists between view controllers
body: <p>I've been trying to get a timer to show at the bottom left corner of my app by using an <code>NSTimer</code>, and making the "elapsed time" show as <code>UILabel</code> on the bottom left corner but it hasn't been working for me.</p>
  
  <pre><code>-(void)viewDidLoad
  {
      NSTimer *aTimer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(aTime) userInfo:nil repeats:YES];
  }
  
  -(void)aTime
  {
      NSLog(@"....Update Function Called....");
  
      static int i = 1;
  
      Label.text = [NSString stringWithFormat:@"%d",i];
  
      i++;
  }
  </code></pre>
  
  <p>The timer actually works but I can't get it to be triggered by a button. I'm trying to get the timer to continue and not restart at 1 when it enters to the next storyboard/xib file. </p>