Question

我有一个使用AVCaptureSession在应用程序内拍照的Swift项目。我很难获得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);
}

终结器会调用capture_cleanup，但我不知道如何设置上下文或指向capture_cleanup函数的指针（甚至是函数定义的样子）

到目前为止，我已经尝试了以下内容，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)

任何转换此内容的帮助都会非常感激！

Answer 1

解决使用桥接到Objective-C代码。通过在我的Swift项目中包含一个CameraController.m Objective-C类（带有相关标题），我可以桥接访问摄像机源。

Objective-C类完成我需要的所有工作，并存储最后拍摄的图像。它还会在拍摄图像后生成通知，允许我的Swift类观察通知并获取最后拍摄的图像。

AVCaptureSession在Swift中清理

1 个答案: