如何在swiftui中用可观察对象协议使两个类相互访问

import SwiftUI
import Combine

class SharedViewModel: ObservableObject {
    @Published var sharedData: String = ""
}

class ClassA {
    @ObservedObject var viewModel: SharedViewModel

    init(viewModel: SharedViewModel) {
        self.viewModel = viewModel
    }

    func updateData(newData: String) {
        viewModel.sharedData = newData
    }
}

class ClassB {
    @ObservedObject var viewModel: SharedViewModel

    init(viewModel: SharedViewModel) {
        self.viewModel = viewModel
    }

    func readData() -> String {
        return viewModel.sharedData
    }
}

struct ContentView: View {
    @StateObject private var viewModel = SharedViewModel()

    var body: some View {
        VStack {
            Text("Shared Data: \(viewModel.sharedData)")
                .padding()

            Button("Update Data") {
                let classA = ClassA(viewModel: viewModel)
                classA.updateData(newData: "New Value")
            }
            .padding()

            Button("Read Data") {
                let classB = ClassB(viewModel: viewModel)
                print("Data from ClassB: \(classB.readData())")
            }
            .padding()
        }
    }
}