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];