我有一个名为AudioRecorder的类和一个名为RecorderView的视图。

• startRecording（）--〉开始录制并获取录制开始时间。
• stopRecording（）--〉停止记录并获取记录停止时间。
• saveToCoreData（）--〉将开始时间、停止时间和额定值保存到核心数据

它的工作原理是，RecorderView允许用户通过调用AudioRecorder中的函数来开始和停止记录。一旦用户停止记录，就会显示一个名为RatingView的新视图。用户在RatingView中提供一个评级，然后点击提交。通过选择提交，将调用RecorderView中的saveToCoreData，其中包含用户提供的评级。这里的问题是，当视图调用saveToCoreData时，startTime和stopTime丢失了。这就是为什么它们是“nil”，只有rating有正确的值。我如何保持startTime和stopTime的活动状态以备下次使用？有没有办法解决这个问题？

import SwiftUI

struct RecorderView: View {
    @ObservedObject var audioRecorder: AudioRecorder
    @State private var showRatingView = false
    
    var body: some View {
        VStack {
            if audioRecorder.recording == false {
                Button(action: {self.audioRecorder.startRecording()}) {
                    Image(systemName: "circle.fill")
                }
            } else {
                Button(action: {self.audioRecorder.stopRecording(); showRatingView = true}) {
                    Image(systemName: "stop.fill")
                }
            }
            VStack {
                if showRatingView == true {
                    NavigationLink(destination: SurveyRatingView(rating: 1, audioRecorder: AudioRecorder()), isActive: self.$showRatingView) { EmptyView()}
                }
            }
        }
    }
}


struct RatingView: View {
    
    @Environment(\.managedObjectContext) var moc
    @State var rating: Int16
    @ObservedObject var audioRecorder: AudioRecorder
    
    @State private var displayNewView: Bool = false
    
    var body: some View {
        VStack {
            
            Text("How was the recording experience?")
//          RatingView(rating: $survey)
            Button(action: {
                self.audioRecorder.saveToCoreData(rating: rating)
            }) {
                Text("Submit Response")
            }
        }
        .navigationBarBackButtonHidden(true)
    }
}

AudioRecorder类如下所示

class AudioRecorder:  NSObject, ObservableObject {
    @Published var startTime: Date
    @Published var stopTime: Date
    
    func startRecording() -> Date {
        self.startTime = Date()
        //Start recording related code here
    }
    
    func stopRecording() -> Date{
        // Stop recording related code here
        self.stopTime = Date()
    }
    
    
    func saveToCoreData(rating: Int16){
        let aRec = AudioRec(context: moc)
        aRec.uuid = UUID()
        aRec.startTime = self.startTime //This is nil
        aRec.stopTime = self.stopTime  //This is nil
        aRec.rating = rating  //Only this has a proper value
        
        try moc.save()
    }
}