在 Swift 3.0 中录制视频时 Flash 不起作用答案

【问题标题】：Flash doesn't work while recording Video in Swift 3.0在 Swift 3.0 中录制视频时 Flash 不起作用
【发布时间】：2016-12-13 06:46:50
【问题描述】：

我正在开发相机应用程序。我使用了一个按钮来在需要时打开和关闭闪光灯模式。此方法非常适用于捕获静止图像，不适用于视频模式。以下是我的代码，请帮忙。 TIA

class func setFlashMode(_ flashMode: AVCaptureFlashMode, for device: AVCaptureDevice) {
    if device.hasFlash && device.isFlashModeSupported(flashMode) {
        do {
            try device.lockForConfiguration()
            device.flashMode = flashMode
            device.unlockForConfiguration()
        }
        catch
        {
            print("Error:-\(error)")
        }
    }
}

Flash 按钮操作

@IBAction func flashButtonClicked(_ sender: UIButton)
{
 sender.isSelected = !sender.isSelected
    if !(sender.isSelected)
    {
        sender.setTitle(NSLocalizedString("OFF", comment: ""), for: UIControlState.normal)
        CameraVC.setFlashMode(AVCaptureFlashMode.off, for: self.videoDeviceInput.device)
    }
    else
    {
        sender.setTitle(NSLocalizedString("ON", comment: ""), for: UIControlState.normal)
        CameraVC.setFlashMode(AVCaptureFlashMode.on, for: self.videoDeviceInput.device)
    }
}

视频按钮操作

@IBAction func videoButtonClicked(_ sender: UIButton)
{       
    self.sessionQueue.async {
        if !self.movieFileOutput.isRecording
        {
            if UIDevice.current.isMultitaskingSupported
            {
                self.backGroundRecordingID = UIApplication.shared.beginBackgroundTask(expirationHandler: nil)
            }

            let connection = self.movieFileOutput.connection(withMediaType: AVMediaTypeVideo)
            let deviceOrientation = UIDevice.current.orientation
            if UIDeviceOrientationIsPortrait(deviceOrientation) || UIDeviceOrientationIsLandscape(deviceOrientation)
            {
                connection?.videoOrientation = self.videoOrientation()
            }

            // Turning ON flash for video recording
            CameraVC.setFlashMode(AVCaptureFlashMode.on, for: self.videoDeviceInput.device)

            let mediaDirectoryURL = SBMediaInfo.mediaDirectoryPath()
            //Unique file name
            let fileName = UIDevice.current.identifierForVendor!.uuidString
            // Start recording to a temporary file.
           let outputFilePath = "\(mediaDirectoryURL.path)/\(fileName).mov"
            self.movieFileOutput.startRecording(toOutputFileURL: URL(fileURLWithPath: outputFilePath), recordingDelegate: self)
            print("\(outputFilePath)")
        }
        else
        {
            self.movieFileOutput.stopRecording()
        }
        sender.isEnabled = true
    }
}

【问题讨论】：

标签： ios swift2 swift3 ios-camera camera-flash

【解决方案1】：

使用了手电筒模式，效果很好。

class func setTorchMode(_ torchMode: AVCaptureTorchMode, for device: AVCaptureDevice) {
    if device.isTorchModeSupported(torchMode) && device.torchMode != torchMode {
        do
        {
            try device.lockForConfiguration()
                device.torchMode = torchMode
                device.unlockForConfiguration()
        }
        catch {
            print("Error:-\(error)")
        }
    }
}

并将其用作

if self.isTorchOn == true
            {
                CameraVC.setTorchMode(AVCaptureTorchMode.on, for: self.videoDeviceInput.device)
            }
            else
            {
                CameraVC.setTorchMode(AVCaptureTorchMode.off, for: self.videoDeviceInput.device)
            }

isTorchOn 是一个布尔值

【讨论】：