title: Why won't my UIActivityIndicatorView stop animating?
body: <p>I am trying to manage the activity indicator from my App Delegate, that way any of my views can put the indicator up.  So, I am adding it as a subview to 'window' and start/stop as follows:</p>
  
  <pre><code>- (void)didStartActivity
  {
      if( activityIndicator == nil ) {
          activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
          activityIndicator.hidesWhenStopped = YES;
          activityIndicator.center = window.center;
          activityIndicator.transform = CGAffineTransformScale(CGAffineTransformIdentity, 6.0, 6.0);
      }
      NSLog(@"%s: starting the activityIndicator", __FUNCTION__);
      [window addSubview:activityIndicator];
      [activityIndicator startAnimating];
  }
  </code></pre>
  
  <p>I see the log messages, so I know the code is being invoked.  The indicator is at the center and 6x the default size.  However, the stopAnimating isn't stopping.  The only thing I can conclude is that it needs to run in the present view controller.</p>
  
  <pre><code>- (void)didStopActivity
  {
      NSLog(@"%s: stopping the activityIndicator", __FUNCTION__);
      [activityIndicator stopAnimating];
      [activityIndicator removeFromSuperview];
  }
  </code></pre>