- (void)highlightButton:(UIButton*)button withDuration:(CGFloat)duration {
  UIImage* image = [button imageForState:UIControlStateNormal];

  UIGraphicsBeginImageContext(image.size);
  CGContextRef context = UIGraphicsGetCurrentContext();
  UIGraphicsPushContext(context);

  [image drawAtPoint:CGPointZero];
  [[UIColor colorWithWhite:1.0 alpha:1.0] set];
  UIRectFillUsingBlendMode(CGRectMake(0, 0, image.size.width, image.size.height), kCGBlendModeSourceIn);

  UIGraphicsPopContext();

  UIImage* mask = UIGraphicsGetImageFromCurrentImageContext();

  UIGraphicsEndImageContext();

  //Add the mask on top of the source button
  UIImageView* imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0,
                                                                         button.frame.size.width, button.frame.size.height)];
  imageView.image = mask;
  imageView.alpha = 0.0;
  [button addSubview:imageView];

  CABasicAnimation* anim = [CABasicAnimation animationWithKeyPath:@"opacity"];
  anim.fromValue = [NSNumber numberWithFloat:0.0];
  anim.toValue = [NSNumber numberWithFloat:0.5];
  anim.repeatCount = 2;
  anim.autoreverses = YES;
  anim.duration = duration/(anim.repeatCount*2);
  [imageView.layer addAnimation:anim forKey:@"opacity"];

  [imageView performSelector:@selector(removeFromSuperview) withObject:nil afterDelay:(anim.repeatCount*anim.duration*2)+.2];
  [imageView release];
}