SwiftUI: PHPicker仍在加载

Question

我正在使用SwiftUI进行一个PHPicker项目。目前一切正常，除了每当我打开选择器时，都会收到警告[Picker] Showing picker unavailable UI (reason: still loading) with error: (null)。

似乎选择器在被调用时没有完全初始化，实际上它在启动时显示Loading Photos...。

有人知道怎么解决这个问题吗？

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我的代码如下：

...
.toolbar {
    ToolbarItem {
        Button(action: {
            showingImagePicker = true
        }) {
            Label("Add Image", systemImage: "plus")
        }
    }
}
.sheet(isPresented: $showingImagePicker) {
    ImagePickerRepresentable(
        showImagePicker: $showingImagePicker,
        onCompletion: complete
    )
}

这是我的ImagePickerRepresentable

struct ImagePickerRepresentable: UIViewControllerRepresentable {
    // MARK: - Environment Object
    @Binding var showImagePicker: Bool
    let onCompletion: (UIImage) -> Void
    
    // MARK: - Coordinator Class
    final class Coordinator: PHPickerViewControllerDelegate {
        private let parent: ImagePickerRepresentable
        
        init(_ parent: ImagePickerRepresentable) {
            self.parent = parent
        }
        
        func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
            parent.showImagePicker = false

            // unpack the selected items
            let itemProviders = results.map(\.itemProvider)
            for itemProvider in itemProviders {
                if itemProvider.canLoadObject(ofClass: UIImage.self) {
                    itemProvider.loadObject(ofClass: UIImage.self) { [weak self] image, error in
                        if let image = image as? UIImage {
                            self?.parent.onCompletion(image)
                        }
                    }
                } else {
                    print("Can't load object")
                }
            }
        }
    }
    
    func makeUIViewController(context: Context) -> PHPickerViewController {
        var configuration = PHPickerConfiguration(photoLibrary: PHPhotoLibrary.shared())
        configuration.filter = .images // filter only to images
        configuration.selectionLimit = 3
        
        let controller = PHPickerViewController(configuration: configuration)
        controller.delegate = context.coordinator // Use Coordinator for delegation
        return controller
    }
    
    func updateUIViewController(_ uiViewController: PHPickerViewController, context: Context) { }
    
    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }
}

提前感谢！

Answer 1

我测试了您的代码，得到了相同的错误，但仍然有效。

如果愿意，可以使用我的选择器版本(元数据变量仅用于Firebase)：

import Foundation
import SwiftUI
import PhotosUI

struct PHPicker: UIViewControllerRepresentable {
    
    //    var didFinishPicking: (_ didSelectItems: Bool) -> Void
    
    @Binding var images: [UIImage]
    @Binding var picker: Bool
    @Binding var imageData: [Data]
    
    var selectionLimitation: Int {
        return 5 - images.count
    }
    
    func makeCoordinator() -> Coordinator {
        return PHPicker.Coordinator(with: self)
    }
    
    
    func makeUIViewController(context: Context) -> PHPickerViewController {
        
        var config = PHPickerConfiguration()
        // can also select videos
        config.filter = .images
        config.selectionLimit = selectionLimitation
        config.preferredAssetRepresentationMode = .current
        let picker = PHPickerViewController(configuration: config)
        picker.delegate = context.coordinator
        return picker
    }
    
    func updateUIViewController(_ uiViewController: PHPickerViewController, context: Context) {
        
    }
    
    class Coordinator: NSObject, PHPickerViewControllerDelegate {
        
        var photoPicker: PHPicker
        
        init(with photoPicker: PHPicker) {
            self.photoPicker = photoPicker
        }
        
        func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
            
            //            photoPicker.didFinishPicking(!results.isEmpty)
            
            // Closing picker
            
            photoPicker.picker.toggle()
            
            for img in results {
                
                if img.itemProvider.canLoadObject(ofClass: UIImage.self) {
                    
                    img.itemProvider.loadObject(ofClass: UIImage.self) { object, err in
                        
                        if let image = object as? UIImage {
                            if let mediaData = image.jpegData(compressionQuality: 0.5) {
                                DispatchQueue.main.async {
                                    self.photoPicker.images.append(image)
                                    self.photoPicker.imageData.append(mediaData)
                                }
                            }
                        }
                        
                        
                        
                    }
                    
                } else {
                    // Error loading
                    print("Cannot be loaded")
                    
                }
            }
       
            
        }
        
        
    }
}

经以下测试：

import SwiftUI

struct ContentView: View {
    
    @State var showingImagePicker = false
    @State var images: [UIImage] = []
    @State var imagesData: [Data] = []
    
    
    var body: some View {
        NavigationView {
            VStack {
                if !images.isEmpty {
                   
                    ForEach(images, id:\.self) { img in
                        Image(uiImage: img)
                            .resizable()
                            .scaledToFit()
                    }
                    
                }
                    
            }
            .toolbar {
                ToolbarItem {
                    Button(action: {
                        showingImagePicker = true
                    }) {
                        Label("Add Image", systemImage: "plus")
                    }
                }
            }
            .sheet(isPresented: $showingImagePicker) {
//                ImagePickerRepresentable(
//                    showImagePicker: $showingImagePicker,
//                    onCompletion: complete
//                )
                PHPicker(images: $images, picker: $showingImagePicker, imageData: $imagesData)
            }
        }
        
    }
    
}