如何为 Xamarin Mac C# 启用相机和麦克风

Question

我正在尝试创建一个非常简单的应用程序，它只是在屏幕上显示相机。

使用的技术是 Xamarin Mac C#

我能够进行研发并获得它的代码，但我的 Mac 不允许该应用程序使用相机。

AVCaptureDevice device;
AVCaptureDeviceInput input;
AVCaptureStillImageOutput output;
AVCaptureSession session;

private bool AuthroizeCamera()
        {
            if(AVCaptureDevice.GetAuthorizationStatus(AVMediaType.Video) == AVAuthorizationStatus.Authorized)
            {
                return true;
            }
            var preferences = new NSUrl("x-apple.systempreferences:com.apple.preference.security?Privacy_Camera");
            var alert = new NSAlert();
            alert.MessageText = "The camera is disabled. Please go to the “Camera” section in Security System Preferences, and enable this app.";
            alert.AddButton("System Preferences");
            alert.AddButton("Cancel");
            var result = alert.RunModal();
            if (result == 1000) {
                NSWorkspace.SharedWorkspace.OpenUrl(preferences);
            }
            return false;
        }

public override void ViewDidLoad()
        {
            base.ViewDidLoad();
            if (AuthroizeCamera())
            {

            }
            device = AVCaptureDevice.GetDefaultDevice(AVMediaType.Video);
            try
            {
                
                input = AVCaptureDeviceInput.FromDevice(device, out var error);
                if (error == null)
                {
                    session = new AVCaptureSession();
                    session.AddInput(input);
                    session.SessionPreset = AVCaptureSession.PresetPhoto;
                    var previewLayer = AVCaptureVideoPreviewLayer.FromSession(session);
                    previewLayer.Frame = this.mainView.Frame;
                    //Control.Layer = previewLayer;
                    this.mainView.Layer = previewLayer;
                    this.mainView.WantsLayer = true;
                    output = new AVCaptureStillImageOutput();
                    session.AddOutput(output);
                    session.StartRunning();
                  
                }
                else
                {
                    var alert = new NSAlert()
                    {
                        AlertStyle = NSAlertStyle.Critical,
                        InformativeText = error.Description,
                        MessageText = "Camera Error",
                    };
                    alert.RunModal();
                }
            }
            catch (Exception ex)
            {
                var alert = new NSAlert()
                {
                    AlertStyle = NSAlertStyle.Critical,
                    InformativeText = ex.ToString(),
                    MessageText = "Camera Error",
                };
                alert.RunModal();
            }

        }

以下代码的问题是，即使首选项打开，我也没有在“相机”或“麦克风”部分看到我的应用程序。

我已经在 AppSandbox、Camera 和 MicroPhone 的权利中授予了权限。 但我没有发现我的相机可以使用。

我是 Mac 开发的新手。