swift 3

Question

我在Swift中使用AVFoundation

通常，当我设置摄像机捕获会话时，我会在objective-c

中执行以下操作

[[cameraView.previewLayer connection] setVideoOrientation:(AVCaptureVideoOrientation)[self interfaceOrientation]]

在swift中，似乎我必须做这样的事情（因为可选类型）

if let connection = cameraView.previewLayer?.connection {
  connection.videoOrientation = self.interfaceOrientation as AVCaptureVideoOrientation
}

然而，这抱怨

‘AVCaptureVideoOrientation’ is not a subtype of ‘UIInterfaceOrientation’

在阅读了关于降级方法之后，这很有意义，但我很难找到如何实现这种方法。

我是否需要编写一个辅助方法，它基本上通过UIInterfaceOrientation的所有可用值执行switch语句来使其工作？

Answer 1

正如我在评论中提到的，由于AVCaptureVideoOrientation和UIInterfaceOrientation与他们的案例不匹配，您可以使用以下内容：

extension AVCaptureVideoOrientation {
    var uiInterfaceOrientation: UIInterfaceOrientation {
        get {
            switch self {
            case .LandscapeLeft:        return .LandscapeLeft
            case .LandscapeRight:       return .LandscapeRight
            case .Portrait:             return .Portrait
            case .PortraitUpsideDown:   return .PortraitUpsideDown
            }
        }
    }

    init(ui:UIInterfaceOrientation) {
        switch ui {
        case .LandscapeRight:       self = .LandscapeRight
        case .LandscapeLeft:        self = .LandscapeLeft
        case .Portrait:             self = .Portrait
        case .PortraitUpsideDown:   self = .PortraitUpsideDown
        default:                    self = .Portrait
        }
    }
}

然后将其用作：

if let connection = cameraView.previewLayer?.connection {
    connection.videoOrientation = AVCaptureVideoOrientation(ui:self.interfaceOrientation)
}

Answer 2

谢谢，大卫。我更新到Swift 3并添加了UIDeviceOrientation：

extension AVCaptureVideoOrientation {
    var uiInterfaceOrientation: UIInterfaceOrientation {
        get {
            switch self {
            case .landscapeLeft:        return .landscapeLeft
            case .landscapeRight:       return .landscapeRight
            case .portrait:             return .portrait
            case .portraitUpsideDown:   return .portraitUpsideDown
            }
        }
    }

    init(ui:UIInterfaceOrientation) {
        switch ui {
        case .landscapeRight:       self = .landscapeRight
        case .landscapeLeft:        self = .landscapeLeft
        case .portrait:             self = .portrait
        case .portraitUpsideDown:   self = .portraitUpsideDown
        default:                    self = .portrait
        }
    }

    init?(orientation:UIDeviceOrientation) {
        switch orientation {
        case .landscapeRight:       self = .landscapeLeft
        case .landscapeLeft:        self = .landscapeRight
        case .portrait:             self = .portrait
        case .portraitUpsideDown:   self = .portraitUpsideDown
        default:
            return nil
        }
    }
}

然后我将它与AVCapturePhotoOutput一起使用，如下所示：

if let connection = imageOutput.connection(withMediaType: AVMediaTypeVideo),
    connection.isVideoOrientationSupported,
    let orientation = AVCaptureVideoOrientation(orientation: UIDevice.current.orientation) {
    connection.videoOrientation = orientation
}

它可能并不适用于所有情况，但由于我的界面不会随方向而改变，因此我会跳过倾听方向更改。

一般来说，更改用户界面可能会更好，这样用户就可以了解他们使用的方向。

Answer 3

swift 3

extension UIDeviceOrientation {
    var videoOrientation: AVCaptureVideoOrientation? {
        // Unlike UIInterfaceOrientation, the UIDeviceOrientation has reversed landscape left/right. Doh!
        switch self {
        case .portraitUpsideDown: return .portraitUpsideDown
        case .landscapeRight: return .landscapeLeft
        case .landscapeLeft: return .landscapeRight
        case .portrait: return .portrait
        default: return nil
        }
    }
}

extension UIInterfaceOrientation {
    var videoOrientation: AVCaptureVideoOrientation? {
        switch self {
        case .portraitUpsideDown: return .portraitUpsideDown
        case .landscapeRight: return .landscapeRight
        case .landscapeLeft: return .landscapeLeft
        case .portrait: return .portrait
        default: return nil
        }
    }
}

Answer 4

过早发布此约10分钟。

想通了，如果你偶然发现了这一点，那就像做

connection.videoOrientation = AVCaptureVideoOrientation.fromRaw(self.interfaceOrientation.toRaw())!

似乎有效。

在Swift中将UIInterfaceOrientation枚举转换为AVCaptureVideoOrientation

4 个答案:

swift 3