IOS 霓虹灯效果

 

#import "ViewController.h"

#define kColorValue arc4random_uniform(256) / 255.0

#define kScreenWidth [UIScreen mainScreen].bounds.size.width

#define kScreenHeight [UIScreen mainScreen].bounds.size.height

 

@interface ViewController ()

 

@end

 

@implementation ViewController

 

- (void)viewDidLoad {

    [super viewDidLoad];

    for (int i  = 0; i < 11; i++) {

        

        UIView *view = [[UIView alloc] initWithFrame:CGRectMake(15*i, 15*i, kScreenWidth - 30 * i, kScreenHeight - 30 * i)];

        

        // 色值的范围(0~255)

        view.backgroundColor = [UIColor colorWithRed:kColorValue green:kColorValue blue:kColorValue alpha:1];

        

        view.tag = 200 + i;

        

        [self.view addSubview:view];

        

        

        

    // Do any additional setup after loading the view, typically from a nib.

}

    [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(changeColor) userInfo:nil repeats:YES]; // 每过一秒去调用changeColor方法,进行一次颜色转换

    

    //[self changeColor];

    

}

 

- (void)changeColor {

    

    UIColor *color = [self.view viewWithTag:200 + 10].backgroundColor;

    

    for (int i = 10; i >= 0; i--) {

        

        [self.view viewWithTag:200 + i].backgroundColor = [self.view viewWithTag:200 + i - 1].backgroundColor; // 先创建的tag值小,结果显示为由外向里转换颜色

        

    }

    

    [self.view viewWithTag:200].backgroundColor = color;

    

}