为什么我的UISlider在IPad Pro上的位置不同？

Question

我有这个滑块，它在我的所有设备中都正确定位，除了我的iPad Pro。我使用下面的代码为我的iPhone和iPad设置滑块，但在Pro上定位已关闭。我该如何解决？

        if UIDevice.currentDevice().userInterfaceIdiom == .Phone {
        let scaleFactor = UIScreen.mainScreen().bounds.width / 320
        let scaleFactor2 = UIScreen.mainScreen().bounds.height / 480

        middleSlider = UISlider(frame: CGRectMake(120 * scaleFactor, 25, 150, 50))
        middleSlider.tintColor = UIColor.whiteColor()
        middleSlider.minimumTrackTintColor = UIColor.whiteColor()
        middleSlider.maximumTrackTintColor = UIColor.whiteColor()
        middleSlider.setThumbImage(UIImage(named: "thumb3"), forState: UIControlState.Normal)
        middleSlider.maximumValue = 2.0
        middleSlider.minimumValue =  0.0
        middleSlider.value = 1.0
        middleSlider.continuous = true
        middleSlider.userInteractionEnabled = false
        self.view?.addSubview(middleSlider)
        }



        if UIDevice.currentDevice().userInterfaceIdiom == .Pad {

        let scaleFactor = UIScreen.mainScreen().bounds.width / 320
        let scaleFactor2 = UIScreen.mainScreen().bounds.height / 480

        middleSlider = UISlider(frame: CGRectMake(110 * scaleFactor, 50, 300, 150))
        middleSlider.tintColor = UIColor.whiteColor()
        middleSlider.setThumbImage(UIImage(named: "thumb3"), forState: UIControlState.Normal)
        middleSlider.minimumTrackTintColor = UIColor.whiteColor()
        middleSlider.maximumTrackTintColor = UIColor.whiteColor()
        middleSlider.maximumValue = 2.0
        middleSlider.minimumValue =  0.0
        middleSlider.value = 1.0
        middleSlider.continuous = true
        middleSlider.userInteractionEnabled = false
        self.view?.addSubview(middleSlider)

        }