在Swift中清理AVCaptureSession

Question

我有一个使用AVCaptureSession在应用内拍照的Swift项目。我很难得到正确的语法来正确清理我的对象。在Obj-C中，建议的代码如下：

// Releases the object - used for late session cleanup 
static void capture_cleanup(void* p) 
{ 
    NewPostPreviewViewController* csc = (NewPostPreviewViewController*)p; 
    [csc release]; // releases capture session if dealloc is called 
} 

// Stops the capture - this stops the capture, and upon stopping completion releases self. 
- (void)stopCapture { 
    // Retain self, it will be released in capture_cleanup. This is to ensure cleanup is done properly, 
    // without the object being released in the middle of it. 
    [self retain]; 

    // Stop the session 
    [session stopRunning]; 

    // Add cleanup code when dispatch queue end 
    dispatch_queue_t queue = dispatch_queue_create("VideoDataOutputQueue", NULL); 
    dispatch_set_context(queue, self); 
    dispatch_set_finalizer_f(queue, capture_cleanup); 
    [dataOutput setSampleBufferDelegate: self queue: queue]; 
    dispatch_release(queue); 
} 

终结会叫capture_cleanup，但我不知道如何设置上下文或指针capture_cleanup功能（甚至函数的定义是什么样子）

到目前为止，我已经试过以下，但我不相信我甚至在正确的轨道上;

let p: UnsafeMutablePointer<NewPostPreviewViewController> = UnsafeMutablePointer.alloc(sizeof(NewPostPreviewViewController)) 
p.initialize(self) 

var videoDataOutputQueue = dispatch_queue_create("VideoDataOutputQueue", nil) 
dispatch_set_context(videoDataOutputQueue, p) 
dispatch_set_finalizer_f(videoDataOutputQueue, ????); 
self.videoDataOutput!.setSampleBufferDelegate(self, queue: videoDataOutputQueue) 
dispatch_release(videoDataOutputQueue) 

任何帮助转换这将是最感谢！

Answer 1

使用桥接到Objective-C代码解决。通过在我的Swift项目中包含一个CameraController.m Objective-C类（带有关联的头文件），我可以桥接访问相机源。

Objective-C类完成我需要的所有工作，并存储最后拍摄的图像。它也会在拍摄图像时产生通知，允许我的Swift类观察通知并获取最后拍摄的图像。