iphone 随机颜色生成

使用类别来为UIColor添加方法：

 #import <UIKit/UIKit.h>

@interface UIColor(Random)

+(UIColor *)randomColor;

@end

 

实现文件：

@implementation UIColor(Random)

+(UIColor *)randomColor

{

    static BOOL seeded = NO;

    if (!seeded) {

        seeded = YES;

        srandom(time(NULL));

    }

    CGFloat red =  (CGFloat)random()/(CGFloat)RAND_MAX;

    CGFloat blue = (CGFloat)random()/(CGFloat)RAND_MAX;

    CGFloat green = (CGFloat)random()/(CGFloat)RAND_MAX;

    return [UIColor colorWithRed:red green:green blue:blue alpha:1.0f];

}

@end