OC - 28.模拟时钟

时间:2023-03-09 15:23:21
OC - 28.模拟时钟

效果图


OC - 28.模拟时钟

实现思路


  • 该示例通过隐式动画实现
  • 表盘通过显示在imageView中的一张图片来实现
  • 在表盘上绘制(时分秒)三条直线,分别位于不同的图层,且时针位于最下层,秒针位于最上层

    • 设置直线为圆角
    • 直线的一段位于表盘的圆心
    • 通过NSTimer定时器,使不同的图层定时执行对应的动画

实现步骤


  • 通过storyboard创建表盘,并拥有它

    @property (weak, nonatomic) IBOutlet UIImageView *clockView;
  • 使用三个成员变量来保存时分秒三根表针位于的不同图层

    @property (nonatomic, weak) CALayer *secondLayer;
    @property (nonatomic, weak) CALayer *minuteLayer;
    @property (nonatomic, weak) CALayer *hourLayer;
  • 初始化所用到的常量

    //将旋转角度转换为弧度制
    #define angleToRadion(angle) ((angle) / 180.0 * M_PI) //秒针每秒钟转过的角度
    #define perSecondAngle 6
    //分针每分钟转过的角度
    #define perMinuteAngle 6
    //时针每小时转过的角度
    #define perHourAngle 30
    //时针每分钟转过的角度
    #define perMuniteHourAngle 0.5
  • 设置时分秒三根表针

    • 设置时针

      - (void)setUpHourLayer
      {
      //创建图层
      CALayer *layer = [CALayer layer];
      layer.backgroundColor = [UIColor blackColor].CGColor;
      layer.cornerRadius = 8; 设置图层的锚点
      layer.anchorPoint = CGPointMake(0.5, 1);
      //设置图层的位置和尺寸
      layer.position = CGPointMake(kClockWith * 0.5, kClockWith * 0.5);
      layer.bounds = CGRectMake(0, 0, 5, kClockWith * 0.5 - 44); //将图层添加到父图层中
      [self.clockView.layer addSublayer:layer];
      self.hourLayer = layer;
      }
    • 设置分针

      - (void)setUpMinuteLayer
      {
      CALayer *layer = [CALayer layer];
      layer.backgroundColor = [UIColor blackColor].CGColor;
      layer.cornerRadius = 4; //设置锚点
      layer.anchorPoint = CGPointMake(0.5, 1); //设置位置和尺寸
      layer.position = CGPointMake(kClockWith * 0.5, kClockWith * 0.5);
      layer.bounds = CGRectMake(0, 0, 3, kClockWith * 0.5 - 34); //将图层添加到父图层中
      [self.clockView.layer addSublayer:layer];
      self.minuteLayer = layer;
      }
    • 设置秒针

      - (void)setUpSecondLayer
      {
      CALayer *layer = [CALayer layer];
      layer.backgroundColor = [UIColor redColor].CGColor; //设置锚点
      layer.anchorPoint = CGPointMake(0.5, 1); //设置位置和尺寸
      layer.position = CGPointMake(kClockWith * 0.5, kClockWith * 0.5);
      layer.bounds = CGRectMake(0, 0, 1, kClockWith * 0.5 - 24); //将图层添加到父图层中
      [self.clockView.layer addSublayer:layer];
      self.secondLayer = layer;
      }
  • 设置定时器,定时执行动画

    [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(timeChange) userInfo:nil repeats:YES];
  • 设置定时器触发时调用的方式,添加动画代码

    - (void)timeChange
    {
    //获取日历对象
    NSCalendar *calendar = [NSCalendar currentCalendar]; //获取日期组件
    NSDateComponents *components = [calendar components:NSCalendarUnitSecond | NSCalendarUnitMinute | NSCalendarUnitHour fromDate:[NSDate date]]; //获取当前的时分秒值
    NSInteger second = components.second;
    NSInteger munite = components.minute;
    NSInteger hour = components.hour; //计算当前时分秒表针转过的角度(弧度制)
    CGFloat secondAngle = angleToRadion(second * perSecondAngle);
    CGFloat muniteAngle = angleToRadion(munite * perMinuteAngle);
    CGFloat hourAngle = angleToRadion(hour *perHourAngle + munite * perMuniteHourAngle); //修改时分秒表针位于的图层的transform属性,执行隐式动画
    self.secondLayer.transform = CATransform3DMakeRotation(secondAngle, 0, 0, 1);
    self.minuteLayer.transform = CATransform3DMakeRotation(muniteAngle, 0, 0, 1);
    self.hourLayer.transform = CATransform3DMakeRotation(hourAngle, 0, 0, 1);
    }