我的 SwiftUI 视图未更新有什么问题？

Question

我正在尝试使用基本的 @State/@Binding 方法操作来更新 View 参数，但它不起作用。这是查看代码：

import SwiftUI

struct StreamingImageView: View {
    @State var imageURL: URL = URL(string: "file:\(NSSearchPathForDirectoriesInDomains(.libraryDirectory, .userDomainMask, true)[0])/../img_01.jpg")!
    var body: some View {
        let _ = FileMonitor(fileURL: $imageURL)
        GeometryReader { geometry in
            AsyncImage(url: imageURL)
                .frame(maxWidth: geometry.size.width, maxHeight: geometry.size.height)
        }
    }
}

FileMonitor 在图像刷新时重新分配 imageURL（已验证）。但是，我没有看到显示的视图已更新。

这是 FileMonitor 中的代码：

class FileMonitor {
    @Binding var fileURL: URL
    let localFileURL: URL
    let fileDescriptor: CInt
    let fileMonitorQueue: DispatchQueue
    let fileMonitorSource: DispatchSourceFileSystemObject

    init(fileURL: Binding<URL>) {
        localFileURL = URL(string: fileURL.wrappedValue.path)!
        self._fileURL = fileURL
        fileDescriptor = open(fileURL.wrappedValue.path(), O_EVTONLY)
        fileMonitorQueue = DispatchQueue(label: "GB.IndigoPolarAlignAid_filemonitor")
        fileMonitorSource = DispatchSource.makeFileSystemObjectSource(fileDescriptor: fileDescriptor, eventMask: .write, queue: fileMonitorQueue)
        startMonitoring()
    }

    func startMonitoring() {
        fileMonitorSource.setEventHandler {
            print("File has been written!")
            // Perform any desired actions here
            self.fileURL = self.localFileURL
        }
...

Answer 1

中断一段时间后我又回到了这个话题。我从编码员那里得到了帮助，但最终结果是黑客攻击（效果不佳）。仅使用 UUID 更新图像。这个想法是，如果源发生变化，视图就会更新，但仍然没有图像更新。这里使用 AsyncImage 是错误的吗？这是新代码：

import SwiftUI

struct StreamingImageView: View {
    private var filePath : URL?
    @StateObject private var monitor : FileMonitor
    @State var id = UUID()
    
    init(){
        filePath = URL(string: "file:/Users/\(NSUserName())/Library/Containers/GB.IndigoPolarAlignAid/Data/img_01.jpg")!
        let monitor = FileMonitor(filePath: filePath!)
        self._monitor = StateObject(wrappedValue: monitor)
        monitor.startMonitoring()
    }
    
    var body: some View {
        GeometryReader { geometry in
            AsyncImage(url: filePath) { image in
                image.image?
                    .resizable().aspectRatio(contentMode: .fit)
                    .frame(maxWidth: geometry.size.width, maxHeight: geometry.size.height)
            }.id(UUID())
            Text("count \(monitor.fileUpdateCount) \(filePath!.absoluteString)")
        }
    }
}