我想用一个按钮来改变sortDescriptor。
但如果我将变量"sorting"和"sortOrder"更改为@State变量，则会出现错误。
错误消息为：* 变量"self. fetchRequest"在初始化之前使用 *

@Environment(\.managedObjectContext) private var viewContext
    
@State var sorting: KeyPath = \Log.diveNr
@State var sortOrder: SortOrder = .forward
    
private var fetchRequest: FetchRequest<Log>
private var logs: FetchedResults<Log> {
    fetchRequest.wrappedValue
}
    
init() {
    fetchRequest = FetchRequest(sortDescriptors: [SortDescriptor(sorting, order: sortOrder)])
}

有人能帮我解决这个问题吗？

• • 解决方案：**

@FetchRequest(sortDescriptors: [SortDescriptor(\.diveNr, order: .forward)])
    var logs: FetchedResults<Log>
    
    var body: some View {
        NavigationStack {
            List{
                if logs.count == 0 {
                    Text("no Logs found")
                }
                Button("change order") {
                    logs.sortDescriptors = [SortDescriptor(\.diveNr, order: .reverse)]
                }
                ForEach(logs){log in
                    NavigationLink(destination: DiveLogDetailView(diveNo: 1, diveSite: "Vela Garska")) {
                        DiveLogListObject(log: log)
                    }
                }
                .onDelete(perform: deleteLog)
            }
}