如何让FlashLight闪烁？

Question

我有以下代码来打开和关闭手电筒：

func toggleTorch(on: Bool) {
    guard let device = AVCaptureDevice.default(for: AVMediaType.video)
        else {return}

    if device.hasTorch {
        do {
            try device.lockForConfiguration()

            if on == true {
                device.torchMode = .on
            } else {
                device.torchMode = .off
            }

            device.unlockForConfiguration()
        } catch {
            print("Torch could not be used")
        }
    } else {
        print("Torch is not available")
    }
}

我想让它一直闪烁直到我按下按钮。我怎么才能做到呢？

Answer 1

你可以试试

var btnNotPressed = true

func blink() {

 if device.hasTorch {
    do {
        try device.lockForConfiguration()

        if on == true {
            device.torchMode = .on
        } else {
            device.torchMode = .off
        }
        // toggle on
        on = !on
        device.unlockForConfiguration()
       // delay until flash shows/hides you can make it 0.5 if you it more fast
       DispatchQueue.main.asyncAfter(deadline:.now() + 1 ) {
         if btnNotPressed {
           self.blink()
         }
       }

    } catch {
        print("Torch could not be used")
    }
  } else {
    print("Torch is not available")
  }
}

然后在按下按钮时设置btnNotPressed