如何在Swift 3中平滑地改变屏幕亮度?

时间:2017-08-22 11:01:54

标签: ios iphone swift

我是iOS应用开发的新手,我试图改变屏幕亮度,但它突然发生了。有没有办法平滑地设置屏幕亮度?

2 个答案:

答案 0 :(得分:3)

我猜你可以像这样设置一个重新发生的计时器:

var timer = Timer.scheduledTimer(timeInterval: 0.05, target: self, selector: #selector(self.update), userInfo: nil, repeats: true)

并添加更新方法:

func update() {
    UIScreen.main.brightness = UIScreen.main.brightness - CGFloat(0.1)
    if UIScreen.main.brightness == CGFloat(0.5) { // or any brightness you want.
        timer.invalidate()
    }
}

只需调整计时器间隔并降低亮度,直到找到所需内容为止。

答案 1 :(得分:3)

而不是计时器,Swift扩展名:

  extension UIScreen {

    private static let step: CGFloat = 0.1

    static func animateBrightness(to value: CGFloat) {
        guard fabs(UIScreen.main.brightness - value) > step else { return }

        let delta = UIScreen.main.brightness > value ? -step : step

        DispatchQueue.main.asyncAfter(deadline: .now() + 0.01) {
            UIScreen.main.brightness += delta
            animateBrightness(to: value)
        }
    }
}