类型'AVCaptureDevice'没有成员'defaultDevice'

Question

使用QR码阅读器。我是编程新手，所以这可能很容易解决。错误是“类型'AVCaptureDevice'没有成员'defaultDevice'”感谢提前帮助！

 //Creating session
    let session = AVCaptureSession()
    //Define capture device
    let captureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)

    do
    {
        let input = try AVCaptureDeviceInput(device: captureDevice)
        session.addInput(input)
    }

Answer 1

您正在使用旧的Swift 2 API。这一行：

let captureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)

应该是：

let captureDevice = AVCaptureDevice.default(for: .video)

Answer 2

这是swift 3.0

System.Diagnostics.Process.Start("calc.exe");

在swift 4.1中     在这里输入代码

let captureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)

我希望这会对你有所帮助