自定义相机视图在 iOS 8/Xcode 6 上不起作用

Question

因此，当我在手机上安装 iOS 7 和 Xcode 5.1（现在在 iOS 8 和 Xcode 6 上）时，我在我的另一个应用程序上使用此代码在自定义相机视图上拍照，相机可以工作，但我不能在我的 leftVertical UIView 中查看相机的实时视图。这是我的代码，不胜感激谢谢！

#import <AVFoundation/AVFoundation.h>

session = [[AVCaptureSession alloc] init];
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone)
    [session setSessionPreset:AVCaptureSessionPreset352x288];
else
    [session setSessionPreset:AVCaptureSessionPreset352x288];

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 = self.leftVertical.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];

Answer 1

试试这个...

在--viewWillAppear中：在主线程开始摄像头捕捉，像这样..

dispatch_async(dispatch_get_main_queue(), ^{

if (![session isRunning])
    {              
            [session startRunning];
    }
});