Category, UIColor类生成随机颜色

借鉴Kitten Yang blog

Xcode -> New File -> Objective-C File

class name:

UIColor

category name:

VSRandomColor

file name:

UIColor+VSRandomColor.h
UIColor+VSRandomColor.m

//UIColor+VSRandomColor.h
@interface UIColor (VSRandomColor)
+ (UIColor *)randomColor;
@end

//UIColor+VSRandomColor.m
@implementation UIColor (VSRandomColor)
+ (UIColor *)randomColor {
    //detail implementation
    //arc4random() % 78 will return a number between 0 and 77, for example.
    CGFloat hue = arc4random() % 100 / 100.0; //色调：0.0 ~ 1.0
    CGFloat saturation = (arc4random() % 50 / 100) + 0.5; //饱和度：0.5 ~ 1.0
    CGFloat brightness = (arc4random() % 50 / 100) + 0.5; //亮度：0.5 ~ 1.0
    
    return [UIColor colorWithHue:hue saturation:saturation brightness:brightness alpha:1];
}
@end

使用的时候：

UIColor *color = [UIColor randomColor];