gistfile1.m

+ (UIImage *)screenShot:(UIView *)aView inRect:(CGRect)aRect
{
    // Arbitrarily masks to 40%. Use whatever level you like
    UIGraphicsBeginImageContext(aRect.size);
    
    CGContextRef context = UIGraphicsGetCurrentContext();
    
    CGContextTranslateCTM(context, 0, -aRect.origin.y);
    
	[aView.layer renderInContext:context];
	UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    CGContextSetRGBFillColor (context, 0, 0, 0, 0.4f);
    CGContextFillRect (context, aRect);
    UIGraphicsEndImageContext();
    
    return image;
}