如何检查iPhone是否有双摄像头？

Question

我正在编写一个照片应用程序，我需要在带有双摄像头的 iPhone 的摄像头视图中使用不同的叠加层（考虑到变焦 ui），是否有正确的方法来检查双摄像头是否存在？

我尝试获取设备并检查它对于非双摄像头 iPhone 是否为零，但它仍然会重新调整设备：

let device = AVCaptureDevice.defaultDevice(withDeviceType: .builtInDualCamera, mediaType: AVMediaTypeVideo, position: .back)

有谁知道如何检测双摄像头？

Answer 1

就像苹果的例子：

if let device = AVCaptureDevice.defaultDevice(withDeviceType: .builtInDuoCamera,
                                                  mediaType: AVMediaTypeVideo,
                                                  position: .back) {
        return device
    } else if let device = AVCaptureDevice.defaultDevice(withDeviceType: .builtInWideAngleCamera,
                                                  mediaType: AVMediaTypeVideo,
                                                  position: .back) {
        return device
    } else {
        return nil
    }

Answer 2

斯威夫特5 ：

var currentDevice:AVCaptureDevice?

     if let device = AVCaptureDevice.default(.builtInDualCamera, for: AVMediaType.video, position: .back) {

                currentDevice = device

         } else if let device = AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back) {

                currentDevice = device

            } else {

                print("Error: no camera available")
            }