我是SwiftUI和手动相机功能的新手，我真的需要帮助。
因此，我尝试构建一个具有UIKit相机作为包装器的SwiftUI相机视图，以通过SwiftUI选择器视图控制聚焦镜头的位置，在焦点值下方显示，并尝试从0开始在AVcaptureDevice.lensPosition之间建立关联到1.0，以及在焦点选择器视图中显示的功能。但是现在，我只想在屏幕上显示该数字。
问题是当我尝试通过协调器焦点观察来更新焦点并将其设置为相机视图模型时，什么也没发生。请帮忙?
这是代码：
import SwiftUI
import AVFoundation
import Combine
struct ContentView: View {
@State private var didTapCapture = false
@State private var focusLensPosition: Float = 0
@ObservedObject var cameraViewModel = CameraViewModel(focusLensPosition: 0)
var body: some View {
VStack {
ZStack {
CameraPreviewRepresentable(didTapCapture: $didTapCapture, cameraViewModel: cameraViewModel)
.frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .center)
VStack {
FocusPicker(selectedFocus: $focusLensPosition)
Text(String(cameraViewModel.focusLensPosition))
.foregroundColor(.red)
.font(.largeTitle)
}
.frame(maxWidth: .infinity, alignment: .leading)
}
.edgesIgnoringSafeArea(.all)
Spacer()
CaptureButton(didTapCapture: $didTapCapture)
.frame(width: 100, height: 100, alignment: .center)
.padding(.bottom, 20)
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
struct CaptureButton: View {
@Binding var didTapCapture : Bool
var body: some View {
Button {
didTapCapture.toggle()
} label: {
Image(systemName: "photo")
.font(.largeTitle)
.padding(30)
.background(Color.red)
.foregroundColor(.white)
.clipShape(Circle())
.overlay(
Circle()
.stroke(Color.red)
)
}
}
}
struct CameraPreviewRepresentable: UIViewControllerRepresentable {
@Environment(\.presentationMode) var presentationMode
@Binding var didTapCapture: Bool
@ObservedObject var cameraViewModel: CameraViewModel
let cameraController: CustomCameraController = CustomCameraController()
func makeUIViewController(context: Context) -> CustomCameraController {
cameraController.delegate = context.coordinator
return cameraController
}
func updateUIViewController(_ cameraViewController: CustomCameraController, context: Context) {
if (self.didTapCapture) {
cameraViewController.didTapRecord()
}
}
func makeCoordinator() -> Coordinator {
Coordinator(self, cameraViewModel: cameraViewModel)
}
class Coordinator: NSObject, UINavigationControllerDelegate, AVCapturePhotoCaptureDelegate {
let parent: CameraPreviewRepresentable
var cameraViewModel: CameraViewModel
var focusLensPositionObserver: NSKeyValueObservation?
init(_ parent: CameraPreviewRepresentable, cameraViewModel: CameraViewModel) {
self.parent = parent
self.cameraViewModel = cameraViewModel
super.init()
focusLensPositionObserver = self.parent.cameraController.currentCamera?.observe(\.lensPosition, options: [.new]) { [weak self] camera, _ in
print(Float(camera.lensPosition))
//announcing changes via Publisher
self?.cameraViewModel.focusLensPosition = camera.lensPosition
}
}
deinit {
focusLensPositionObserver = nil
}
func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
parent.didTapCapture = false
if let imageData = photo.fileDataRepresentation(), let image = UIImage(data: imageData) {
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
}
parent.presentationMode.wrappedValue.dismiss()
}
}
}
class CameraViewModel: ObservableObject {
@Published var focusLensPosition: Float = 0
init(focusLensPosition: Float) {
self.focusLensPosition = focusLensPosition
}
}
class CustomCameraController: UIViewController {
var image: UIImage?
var captureSession = AVCaptureSession()
var backCamera: AVCaptureDevice?
var frontCamera: AVCaptureDevice?
var currentCamera: AVCaptureDevice?
var photoOutput: AVCapturePhotoOutput?
var cameraPreviewLayer: AVCaptureVideoPreviewLayer?
//DELEGATE
var delegate: AVCapturePhotoCaptureDelegate?
func showFocusLensPosition() -> Float {
// guard let camera = currentCamera else { return 0 }
// try! currentCamera!.lockForConfiguration()
// currentCamera!.focusMode = .autoFocus
//// currentCamera!.setFocusModeLocked(lensPosition: currentCamera!.lensPosition, completionHandler: nil)
// currentCamera!.unlockForConfiguration()
return currentCamera!.lensPosition
}
func didTapRecord() {
let settings = AVCapturePhotoSettings()
photoOutput?.capturePhoto(with: settings, delegate: delegate!)
}
override func viewDidLoad() {
super.viewDidLoad()
setup()
}
func setup() {
setupCaptureSession()
setupDevice()
setupInputOutput()
setupPreviewLayer()
startRunningCaptureSession()
}
func setupCaptureSession() {
captureSession.sessionPreset = .photo
}
func setupDevice() {
let deviceDiscoverySession =
AVCaptureDevice.DiscoverySession(deviceTypes: [.builtInWideAngleCamera],
mediaType: .video,
position: .unspecified)
for device in deviceDiscoverySession.devices {
switch device.position {
case .front:
self.frontCamera = device
case .back:
self.backCamera = device
default:
break
}
}
self.currentCamera = self.backCamera
}
func setupInputOutput() {
do {
let captureDeviceInput = try AVCaptureDeviceInput(device: currentCamera!)
captureSession.addInput(captureDeviceInput)
photoOutput = AVCapturePhotoOutput()
captureSession.addOutput(photoOutput!)
} catch {
print(error)
}
}
func setupPreviewLayer() {
self.cameraPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
self.cameraPreviewLayer?.videoGravity = AVLayerVideoGravity.resizeAspectFill
let deviceOrientation = UIDevice.current.orientation
cameraPreviewLayer?.connection?.videoOrientation = AVCaptureVideoOrientation(rawValue: deviceOrientation.rawValue)!
self.cameraPreviewLayer?.frame = self.view.frame
// view.transform = CGAffineTransform(scaleX: 0.5, y: 0.5)
self.view.layer.insertSublayer(cameraPreviewLayer!, at: 0)
}
func startRunningCaptureSession() {
captureSession.startRunning()
}
}
struct FocusPicker: View {
var feets = ["∞ ft", "30", "15", "10", "7", "5", "4", "3.5", "3", "2.5", "2", "1.5", "1", "0.5", "Auto"]
@Binding var selectedFocus: Float
var body: some View {
Picker(selection: $selectedFocus, label: Text("")) {
ForEach(0 ..< feets.count) {
Text(feets[$0])
.foregroundColor(.white)
.font(.subheadline)
.fontWeight(.medium)
}
.animation(.none)
.background(Color.clear)
.pickerStyle(WheelPickerStyle())
}
.frame(width: 60, height: 200)
.border(Color.gray, width: 5)
.clipped()
}
}
答案 0 :(得分：1)
您提供的代码存在问题，即selectedFocus视图中FocusPicker的类型应为Integer而不是Float。因此，一种选择是将该类型更改为Integer，并找到一种方法将AVCaptureDevice.lensPosition表示为具有给定范围的Integer。
第二个选项是用枚举替换foots数组。通过使枚举符合CustomStringConvertible协议，您甚至可以提供适当的描述。请在下面查看我的示例。
由于您只是想在第一步中显示数字，因此我已经剥离了一些代码，因此代码更容易理解。
我的工作示例：
import SwiftUI
import Combine
struct ContentView: View {
@ObservedObject var cameraViewModel = CameraViewModel(focusLensPosition: 0.5)
var body: some View {
VStack {
ZStack {
VStack {
FocusPicker(selectedFocus: $cameraViewModel.focusLensPosition)
Text(String(self.cameraViewModel.focusLensPosition))
.foregroundColor(.red)
.font(.largeTitle)
}
.frame(maxWidth: .infinity, alignment: .leading)
}
.edgesIgnoringSafeArea(.all)
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
class CameraViewModel: ObservableObject {
@Published var focusLensPosition: Float
init(focusLensPosition: Float) {
self.focusLensPosition = focusLensPosition
}
}
enum Feets: Float, CustomStringConvertible, CaseIterable, Identifiable {
case case1 = 0.0
case case2 = 0.5
case case3 = 1.0
var id: Float { self.rawValue }
var description: String {
get {
switch self {
case .case1:
return "∞ ft"
case .case2:
return "4"
case .case3:
return "Auto"
}
}
}
}
struct FocusPicker: View {
@Binding var selectedFocus: Float
var body: some View {
Picker(selection: $selectedFocus, label: Text("")) {
ForEach(Feets.allCases) { feet in
Text(feet.description)
}
.animation(.none)
.background(Color.clear)
.pickerStyle(WheelPickerStyle())
}
.frame(width: 60, height: 200)
.border(Color.gray, width: 5)
.clipped()
}
}