swift – tvOS中意外的运动效应振荡

import UIKit  

@UIApplicationMain  
class AppDelegate: UIResponder, UIApplicationDelegate {  
    var window: UIWindow?  

    func application(application: UIApplication,  
                     didFinishLaunchingWithOptions launchOptions: 
                                               [NSObject: AnyObject]?) -> Bool {  
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)  
        self.window!.rootViewController = ExampleController()  
        self.window!.makeKeyAndVisible()  
        return true  
    }  
}  
class ExampleController: UIViewController {  
    override func viewDidLoad() {  
        super.viewDidLoad()  

        let redView = UIView(frame: CGRect(x: 200, y: 200, 
                                           width: 800, height: 500))  
        redView.backgroundColor = UIColor.redColor().colorWithAlphaComponent(0.5)  
        self.view.addSubview(redView)  

        let effect = UIInterpolatingMotionEffect(keyPath: "center.x", 
                                                 type: .TiltAlongHorizontalAxis)  
        effect.minimumRelativeValue = -100  
        effect.maximumRelativeValue = 100  

        let effectGroup = UIMotionEffectGroup()  
        effectGroup.motionEffects = [effect]  

        redView.motionEffects = [effectGroup]  
    }
}

在Simulator和新Apple TV上导致以下行为

有没有办法避免振荡？

public class MyMotionEffect : UIInterpolatingMotionEffect {
    public override func keyPathsAndRelativeValuesForViewerOffset(viewerOffset: UIOffset) -> [String : AnyObject]? {
        print("\(viewerOffset.horizontal)")

        return super.keyPathsAndRelativeValuesForViewerOffset(viewerOffset);
    }
}

过了一会儿,我可以重现振荡.生成的(水平)偏移量具有以下图表：

您可以看到倾斜中已经存在振荡.设备似乎一次产生两个倾斜.

一种解决方案是添加启发式方法(将偏移值与前两个进行比较并忽略是否存在符号更改,或忽略具有突然更改的偏移.不幸的是,这两种解决方案都不完美).最好的解决方案可能是直接使用Core Motion并完全避免本机转换.或者使用较小的距离,因为振动将不可见.