SwiftUI AspectRatio 不适用于来自相机的图像

Question

我不确定这是否是 SwiftUI 特有的问题。无论如何，我有一个 UIImagePickerController，我使用 UIViewControllerRepresentableProtocol 将它实现到 SwiftUI 视图中：

struct ContentView: View {

@State var showCameraView = false
@State var showImagePicker = false
@State var UserImage = Image("user")

var body: some View {
    VStack {
        UserImage
            .resizable()
            .frame(width: 200, height: 200)
            .scaledToFit()
            .background(Color.gray)
            .cornerRadius(200)
            .clipped()
        Button(action: {self.showImagePicker = true}) {
            Text("Choose from camera roll")
        }
            .padding(.top, 10)
    }
        .sheet(isPresented: $showImagePicker) {
            ImagePicker(showImagePicker: self.$showImagePicker, pickedImage: self.$UserImage)
            }

}

}

struct ImagePicker: UIViewControllerRepresentable {

@Binding var showImagePicker: Bool
@Binding var pickedImage: Image

func makeCoordinator() -> ImagePicker.Coordinator {
    Coordinator(self)
}

func makeUIViewController(context: UIViewControllerRepresentableContext<ImagePicker>) -> UIImagePickerController {
    let imagePicker = UIImagePickerController()
    imagePicker.delegate = context.coordinator
    return imagePicker
}

func updateUIViewController(_ uiViewController: UIImagePickerController, context: UIViewControllerRepresentableContext<ImagePicker>) {
    return
}

class Coordinator: NSObject, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    var parent: ImagePicker

    init(_ imagePicker: ImagePicker) {
        self.parent = imagePicker
    }

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        let uiImage = info[UIImagePickerController.InfoKey.originalImage] as! UIImage
        parent.pickedImage = Image(uiImage: uiImage)
        parent.showImagePicker = false
    }

    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
        parent.showImagePicker = false
    }
}

}

当设备摄像机不拍摄的图像时，它可以正常工作。但是，每次我选择相机本身拍摄的图像时，似乎都没有应用 .aspectRatio 修饰符，因为在这种情况下加载的图像的尺寸会失真。有人发现我的代码有问题或知道解决方案吗？

Answer 1

我遇到了同样的问题。我没有意识到这是 SwiftUI 的不足！现在我已经应用了 ninjahamster 的解决方法。

我的代码在这里，以防有人需要参考。查看 func didFinishPickingMediaWithInfo 的变化。

import SwiftUI

final class ImagePickerCoordinator: NSObject {
    @Binding var image: UIImage?
    @Binding var takePhoto: Bool

    init(image: Binding<UIImage?>, takePhoto: Binding<Bool>) {
        _image = image
        _takePhoto = takePhoto
    }
}

struct ImagePicker: UIViewControllerRepresentable {
    @Binding var image: UIImage?
    @Binding var takePhoto: Bool

    func makeCoordinator() -> ImagePickerCoordinator {
        ImagePickerCoordinator(image: $image, takePhoto: $takePhoto)
    }

    func makeUIViewController(context: Context) -> UIImagePickerController {
        let pickerController = UIImagePickerController()
        pickerController.delegate = context.coordinator
        return pickerController
    }

    func updateUIViewController(_ uiViewController: UIImagePickerController, context: Context) {
        switch self.takePhoto {
        case true:
            uiViewController.sourceType = .camera
            uiViewController.showsCameraControls = true
        case false:
            uiViewController.sourceType = .photoLibrary
        }
        uiViewController.allowsEditing = false
    }
}

extension ImagePickerCoordinator: UINavigationControllerDelegate, UIImagePickerControllerDelegate {
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        if let imageOriginal = info[.originalImage] as? UIImage {
//            image = imageOriginal
            image = resizeImage(image: imageOriginal)
        }
        if let imageEdited = info[.editedImage] as? UIImage {
            image = imageEdited
        }

        picker.dismiss(animated: true, completion: nil)
    }

    func resizeImage(image: UIImage) -> UIImage {
        let width = image.size.width
        let height = image.size.height
        UIGraphicsBeginImageContext(CGSize(width: width, height: height))
        image.draw(in: CGRect(x: 0, y: 0, width: width, height: height))
        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return newImage!
    }

    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
        picker.dismiss(animated: true, completion: nil)
    }
}

Answer 2

有同样的问题。我使用了@ninjahamster 提出的修改版本，我根本没有调整图像大小。欢迎任何其他解决方案。

    func resizeImage(image: UIImage) -> UIImage {
        let width = image.size.width
        let height = image.size.height
        UIGraphicsBeginImageContext(CGSize(width: width, height: height))
        image.draw(in: CGRect(x: 0, y: 0, width: width, height: height))
        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return newImage!
    }

Answer 3

我也遇到了同样的问题。我没有找到解决方案，而是一种解决方法。 我使用协调器类中的函数调整了图像的大小，然后将其返回到视图中。对我有用。

func resizeImage(image: UIImage) -> UIImage {
    let scale = 300 / image.size.width
    let newHeight = image.size.height * scale
    UIGraphicsBeginImageContext(CGSize(width: 300, height: newHeight))
    image.draw(in: CGRect(x: 0, y: 0, width: 300, height: newHeight))
    let newImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    return newImage!
}