-(UIColor *) radomColor{
CGFloat red = arc4random_uniform(255) / 255.0;
CGFloat green = arc4random_uniform(255) / 255.0;
CGFloat blue = arc4random_uniform(255) / 255.0;
return [UIColor colorWithRed:red green:green blue:blue alpha:1.0f];
}
原文：http://www.cnblogs.com/wlxm/p/4295915.html