类型'AVCapturePhotoSettings‘的值没有成员'availablePreviewPhotoPixelFormatTypes’

Question

@objc func launchCoreML() {
    let settings = AVCapturePhotoSettings()
    let previewPixelType = settings.availablePreviewPhotoPixelFormatTypes.first
    let previewFormat = [
        kCVPixelBufferPixelFormatTypeKey as String: previewPixelType, 
        kCVPixelBufferWidthKey as String: 160, 
        kCVPixelBufferHeightKey as String: 160
    ] as [String : Any]

    settings.previewPhotoFormat = previewFormat
    cameraOutput.capturePhoto(with: settings, delegate: self)
}

我说错了：

类型'AVCapturePhotoSettings‘的值没有成员'availablePreviewPhotoPixelFormat’。

我正在使用Xcode 9的beta版本。

Answer 1

在beta 4中，它被重命名为__availablePreviewPhotoPixelFormat。我还没看过beta 5。

Answer 2

在升级到Xcode 12.0之后，我也遇到了同样的问题

在最后的Xcode发行版: 12.0版(12A7209)中，settings.availablePreviewPhotoPixelFormatTypes又被更改为settings.__availablePreviewPhotoPixelFormatTypes。至少两年来，我一直在使用它而不用“重命名”。Thx @Matthijs Hollemans寻求帮助

编辑:这是官方对这一变化的回应：https://developer.apple.com/forums/thread/86810?answerId=259270022#259270022

这段代码编译OK。

let settings = AVCapturePhotoSettings()
guard let previewPixelType = settings.__availablePreviewPhotoPixelFormatTypes.first else { return }
let previewFormat = [
    kCVPixelBufferPixelFormatTypeKey as String: previewPixelType,
    kCVPixelBufferWidthKey as String: 160,
    kCVPixelBufferHeightKey as String: 160
]
settings.previewPhotoFormat = previewFormat
output.capturePhoto(with: settings, delegate: self)

Answer 3

        var photoSettings: AVCapturePhotoSettings
        if #available(iOS 11.0, *) {
            photoSettings = AVCapturePhotoSettings.init(format: [AVVideoCodecKey: AVVideoCodecType.jpeg])
        } else {
            // Fallback on earlier versions
            photoSettings = AVCapturePhotoSettings()
            if photoSettings.__availablePreviewPhotoPixelFormatTypes.count > 0 {
                photoSettings.previewPhotoFormat = [kCVPixelBufferPixelFormatTypeKey as String : photoSettings.__availablePreviewPhotoPixelFormatTypes.first!]
            }
        }