AVFoundation 相机不可见

AVFoundation camera not visible

我刚开始使用 AVFoundation,我正在尝试捕获一个 image.The 问题是我能够捕获图像但无法在我的 view.Here 中看到相机是我的代码:

     session = [AVCaptureSession new];
if([session canSetSessionPreset:AVCaptureSessionPresetHigh])
 [session setSessionPreset:AVCaptureSessionPresetHigh];//specifies photo quality

AVCaptureDevice *inputDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
NSError *error;
AVCaptureDeviceInput *deviceInput = [AVCaptureDeviceInput deviceInputWithDevice:inputDevice error:&error];
[session addInput:deviceInput];

AVCaptureVideoPreviewLayer *previewLayer = [[AVCaptureVideoPreviewLayer alloc]initWithSession:session];
[previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
CALayer *rootLayer = [[self view]layer];
[rootLayer setMasksToBounds:YES];
[previewLayer setFrame:_cameraView.frame];
[rootLayer insertSublayer:previewLayer atIndex:0];

stillImageOutput = [AVCaptureStillImageOutput new];
[stillImageOutput setOutputSettings:[[NSDictionary alloc]initWithObjectsAndKeys:AVVideoCodecJPEG,AVVideoCodecKey,nil]];
[session addOutput:stillImageOutput];
    [session startRunning];

我的代码有问题吗?

尝试[[rootLayer layer] addSublayer:previewLayer];

对我来说很管用!