Swift利用纯代码实现时钟效果实例代码

//创建一个时针VIEW
 let hourView:UIView! = UIView.init()
 hourView.center = self.view.center
 hourView.layer.bounds = CGRect(x: 0, y: 0, width: 2, height: hourLength)
 hourView.backgroundColor = PolarTheme.bottomColor
 hourView.layer.anchorPoint = CGPoint(x: 1, y: 1)
 hourView.layer.cornerRadius = 1
 self.hourView = hourView
 self.view.addSubview(self.hourView)

 //创建一个分针VIEW
 let minuteView:UIView! = UIView.init()
 minuteView.center = self.view.center
 minuteView.layer.bounds = CGRect(x: 0, y: 0, width: Int(1.5), height: Int(minuteLength))
 minuteView.backgroundColor = PolarTheme.bottomColor
 minuteView.layer.anchorPoint = CGPoint(x: 1, y: 1)

 self.minuteView = minuteView
 self.view.addSubview(self.minuteView)


 //创建一个秒针VIEW
 let secondView:UIView! = UIView.init()
 secondView.center = self.view.center
 secondView.layer.bounds = CGRect(x: 0, y: 0, width: 1, height: secondLength)
 secondView.backgroundColor = PolarTheme.topColor
 secondView.layer.anchorPoint = CGPoint(x: 1, y: 1)
 self.secondView = secondView
 self.view.addSubview(self.secondView)

var timer:Timer!

timer = Timer.scheduledTimer(timeInterval: 0.2,target:self,selector:#selector(PolarViewController.move),userInfo:nil,repeats:true)

func move(){
 var angleSecond:CGFloat = CGFloat(Double.pi * 2/60.0)
 var angleMinute:CGFloat = CGFloat(Double.pi * 2/60.0)
 var angleHour:CGFloat = CGFloat(Double.pi * 2/12.0)

 //当前时间
 let date = Date()
 let calendar = NSCalendar.current

 let secondInt = CGFloat(calendar.component(.second, from: date))
 let minuteInt = CGFloat(calendar.component(.minute, from: date))
 let hourInt = CGFloat(calendar.component(.hour, from: date))

 //计算旋转角度
 angleSecond = angleSecond * secondInt
 angleMinute = angleMinute * minuteInt + angleSecond/60.0
 angleHour = angleHour * hourInt + angleMinute/60.0

 //保持中心点
 self.secondView.center = self.view.center
 self.minuteView.center = self.view.center
 self.hourView.center = self.view.center
 //旋转各自的角度
 self.secondView.transform = CGAffineTransform(rotationAngle: angleSecond)
 self.minuteView.transform = CGAffineTransform(rotationAngle: angleMinute)
 self.hourView.transform = CGAffineTransform(rotationAngle: angleHour)
}

override func willRotate(to toInterfaceOrientation: UIInterfaceOrientation, duration: TimeInterval) {
 move()
}