gistfile1.m

[SVProgressHUD show];

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void) {
    
  for(id object in objects) {
      // CPU heavy code
      dispatch_async(dispatch_get_main_queue(), ^ {
          [SVProgressHUD showProgress:x];
      });
  }

  dispatch_async(dispatch_get_main_queue(), ^ {
      [SVProgressHUD dismiss];
  });
});