ios - 在 ios 的 opentok 上更改相机

Question

我正在尝试更改 OpenTok 中发布者的摄像头。在 Android 中它非常简单，但我不明白如何在 ios 的 objective c 中做到这一点。

我试过了:

if (_publisher.cameraPosition == AVCaptureDevicePositionFront) 
{
    _publisher.cameraPosition = AVCaptureDevicePositionBack; // back camera

} else 
{
    _publisher.cameraPosition = AVCaptureDevicePositionFront; // front camera
}

我不得不说我是 Objective C(和 OpenTok)的初学者。

我该怎么办？

谢谢你:)

Answer 1

试试这个:

func setCameraPosition(_ position: AVCaptureDevicePosition) -> Bool {
        guard let preset = captureSession?.sessionPreset else {
            return false
        }

        let newVideoInput: AVCaptureDeviceInput? = {
            do {
                if position == AVCaptureDevicePosition.back {
                    return try AVCaptureDeviceInput.init(device: backFacingCamera())
                } else if position == AVCaptureDevicePosition.front {
                    return try AVCaptureDeviceInput.init(device: frontFacingCamera())
                } else {
                    return nil
                }
            } catch {
                return nil
            }
        }()

        guard let newInput = newVideoInput else {
            return false
        }

        var success = true

        captureQueue.sync {
            captureSession?.beginConfiguration()
            captureSession?.removeInput(videoInput)

            if captureSession?.canAddInput(newInput) ?? false {
                captureSession?.addInput(newInput)
                videoInput = newInput
            } else {
                success = false
                captureSession?.addInput(videoInput)
            }

            captureSession?.commitConfiguration()
        }

        if success {
            capturePreset = preset
        }

        return success
    }

    func toggleCameraPosition() -> Bool {
        guard hasMultipleCameras else {
            return false
        }

        if  videoInput?.device.position == .front {
            return setCameraPosition(.back)
        } else {
            return setCameraPosition(.front)
        }
    }