iOS实现漂亮的时钟代码
1.最终效果图
2.实现思路
- 在ios中默认是绕着中心点旋转的，因为锚点默认在图层的中点，要想绕着下边中心点转，需要改变图层锚点的位置。
- 根据锚点，设置position坐标，为时钟的中点。
- 思考秒针旋转的角度，怎么知道当前秒针旋转到哪，当前秒针旋转的角度 = 当前秒数 * 每秒转多少°。
1> 计算一秒转多少° 360 * 60 = 6
2> 获取当前秒数，通过日历对象，获取日期组成成分 NSCalendar -> NSDateComponents -> 获取当前秒数 - 每隔一秒，获取最新秒数，更新时钟。
- 分钟一样的做法
- 时钟也一样
- 每一分钟，时钟也需要旋转，60分钟 -> 1小时 - > 30° ==》 每分钟 30 / 60.0 一分钟时针转0.5°
- 把时针和秒针头尾变尖，设置圆角半径
2.完整代码
#import "ViewController.h" //获得当前的年月日 时分秒 #define CURRENTSEC [[NSCalendar currentCalendar] component:NSCalendarUnitSecond fromDate:[NSDate date]] #define CURRENTMIN [[NSCalendar currentCalendar] component:NSCalendarUnitMinute fromDate:[NSDate date]] #define CURRENTHOUR [[NSCalendar currentCalendar] component:NSCalendarUnitHour fromDate:[NSDate date]] #define CURRENTDAY [[NSCalendar currentCalendar] component:NSCalendarUnitDay fromDate:[NSDate date]] #define CURRENTMONTH [[NSCalendar currentCalendar] component:NSCalendarUnitMonth fromDate:[NSDate date]] #define CURRENTYEAR [[NSCalendar currentCalendar] component:NSCalendarUnitYear fromDate:[NSDate date]] //角度转换成弧度 #define ANGEL(x) x/180.0 * M_PI #define kPerSecondA ANGEL(6) #define kPerMinuteA ANGEL(6) #define kPerHourA ANGEL(30) #define kPerHourMinuteA ANGEL(0.5) @interface ViewController () @property (nonatomic,strong) UIImageView *imageClock; @property (nonatomic,strong) CALayer *layerSec; @property (nonatomic,strong) CALayer *layerMin; @property (nonatomic,strong) CALayer *layerHour; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; [self.view addSubview:self.imageClock]; [self.imageClock.layer addSublayer:self.layerSec]; [self.imageClock.layer addSublayer:self.layerMin]; [self.imageClock.layer addSublayer:self.layerHour]; [self timeChange]; [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(timeChange) userInfo:nil repeats:YES]; // Do any additional setup after loading the view, typically from a nib. } - (void)timeChange { self.layerSec.transform = CATransform3DMakeRotation(CURRENTSEC * kPerSecondA, 0, 0, 1); self.layerMin.transform = CATransform3DMakeRotation(CURRENTMIN * kPerMinuteA, 0, 0, 1); self.layerHour.transform = CATransform3DMakeRotation(CURRENTHOUR * kPerHourA, 0, 0, 1); self.layerHour.transform = CATransform3DMakeRotation(CURRENTMIN * kPerHourMinuteA + CURRENTHOUR*kPerHourA, 0, 0, 1); } - (UIImageView *)imageClock { if (_imageClock == nil) { _imageClock = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"钟表"]]; _imageClock.frame = CGRectMake(100, 100, 200, 200); } return _imageClock; } - (CALayer *)layerSec { if (_layerSec == nil) { _layerSec = [CALayer layer]; _layerSec.bounds = CGRectMake(0, 0, 2, 80); _layerSec.backgroundColor = [UIColor redColor].CGColor; _layerSec.cornerRadius = 5; _layerSec.anchorPoint = CGPointMake(0.5, 1); _layerSec.position = CGPointMake(self.imageClock.bounds.size.width/2, self.imageClock.bounds.size.height/2); } return _layerSec; } - (CALayer *)layerMin { if (_layerMin == nil) { _layerMin = [CALayer layer]; _layerMin.bounds = CGRectMake(0, 0, 4, 60); _layerMin.backgroundColor = [UIColor blackColor].CGColor; _layerMin.cornerRadius = 5; _layerMin.anchorPoint = CGPointMake(0.5, 1); _layerMin.position = CGPointMake(self.imageClock.bounds.size.width/2, self.imageClock.bounds.size.height/2); } return _layerMin; } - (CALayer *)layerHour { if (_layerHour == nil) { _layerHour = [CALayer layer]; _layerHour.bounds = CGRectMake(0, 0, 6, 40); _layerHour.backgroundColor = [UIColor blackColor].CGColor; _layerHour.cornerRadius = 5; _layerHour.anchorPoint = CGPointMake(0.5, 1); _layerHour.position = CGPointMake(self.imageClock.bounds.size.width/2, self.imageClock.bounds.size.height/2); } return _layerHour; }