0
我正在爲我的應用程序製作自定義相機功能，但是當我從應用程序中退出時，相機被凍結。我怎樣才能解決這個問題？當我回到應用程序（Obj-C）時，相機被凍結
我想在用戶再次打開應用程序時恢復照相機，而不必關閉應用程序並重新打開應用程序。
代碼：
AVCaptureSession *session;
AVCaptureStillImageOutput *stillImageOutput;
- (void)viewWillAppear:(BOOL)animated
{
session = [[AVCaptureSession alloc] init];
[session setSessionPreset:AVCaptureSessionPresetPhoto];
AVCaptureDevice *inputDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
NSError *error;
AVCaptureDeviceInput *deviceInput = [AVCaptureDeviceInput deviceInputWithDevice:inputDevice error:&error];
if ([session canAddInput:deviceInput]) {
[session addInput:deviceInput];
}
AVCaptureVideoPreviewLayer *previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
[previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
CALayer *rootLayer = [[self view] layer];
[rootLayer setMasksToBounds:YES];
CGRect frame = frameForCapture.frame;
[previewLayer setFrame:frame];
[rootLayer insertSublayer:previewLayer atIndex:0];
stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys:AVVideoCodecJPEG, AVVideoCodecKey, nil];
[stillImageOutput setOutputSettings:outputSettings];
[session addOutput:stillImageOutput];
[session startRunning];
crossButton.hidden = YES;
}
- (IBAction)takePhoto:(id)sender
{
AVCaptureConnection *videoConnection = nil;
for (AVCaptureConnection *connection in stillImageOutput.connections) {
for (AVCaptureInputPort *port in [connection inputPorts]) {
if ([[port mediaType] isEqual:AVMediaTypeVideo]) {
videoConnection = connection;
crossButton.hidden = NO;
cameraButton.hidden = YES;
break;
}
}
}
[stillImageOutput captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
if (imageDataSampleBuffer != NULL) {
NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
UIImage *image = [UIImage imageWithData:imageData];
imageView.image = image;
}
}];
}