随机色的宏

/** 随机色的宏 */

#define random(r, g, b, a) [UIColor colorWithRed:(r)/255.0green:(g)/255.0blue:(b)/255.0alpha:(a)/255.0]

#define randomColor random(arc4random_uniform(256), arc4random_uniform(256), arc4random_uniform(256), arc4random_uniform(256))