IOS CoreMotion

import UIKit

import CoreMotion

class ViewController: UIViewController,UIAccelerometerDelegate {

var ball:UIImageView!
var speedX:UIAccelerationValue=0
var speedY:UIAccelerationValue=0
var motionManager = CMMotionManager()

override func viewDidLoad() {
super.viewDidLoad()
//放一个小球在中央
ball=UIImageView(image:UIImage(named:"ball"))
ball.frame=CGRectMake(0,0,50,50)
ball.center=self.view.center
self.view.addSubview(ball)

motionManager.accelerometerUpdateInterval = 1/60

if(motionManager.accelerometerAvailable)
{
let queue = NSOperationQueue.currentQueue()
motionManager.startAccelerometerUpdatesToQueue(queue!, withHandler:
{ (accelerometerData : CMAccelerometerData?, error: NSError?) -> Void in

//动态设置小球位置
self.speedX += accelerometerData!.acceleration.x
self.speedY += accelerometerData!.acceleration.y
var posX=self.ball.center.x + CGFloat(self.speedX)
var posY=self.ball.center.y - CGFloat(self.speedY)
//碰到边框后的反弹处理
if posX<0 {
posX=0;
//碰到左边的边框后以0.4倍的速度反弹
self.speedX *= -0.4

}else if posX > self.view.bounds.size.width {
posX=self.view.bounds.size.width
//碰到右边的边框后以0.4倍的速度反弹
self.speedX *= -0.4
}
if posY<0 {
posY=0
//碰到上面的边框不反弹
self.speedY=0
} else if posY>self.view.bounds.size.height{
posY=self.view.bounds.size.height
//碰到下面的边框以1.5倍的速度反弹
self.speedY *= -1.5
}
self.ball.center=CGPointMake(posX,posY)
})
}
}
}