List view is not updating when iCloud is activated

Question

The following code is working perfectly fine when iCloud is deactivated. A meeting object is saved to the DB and the list on ContentView is updated properly.

But when I activate iCloud the list is not longer updated.

I tried already to wrap the meeting object with @State and loaded/updated the @Bindable property .onAppear/.onDisappear. But without any effect.

import SwiftData
import SwiftUI

@main
struct SwiftDataRelationNavigationApp: App {
    
    var body: some Scene {
        WindowGroup {
            ContentView()
                .modelContainer(for: Meeting.self)
        }
    }
}

import SwiftData
import SwiftUI
import UniformTypeIdentifiers

@Model
class Meeting {
    var id: UUID = UUID()
    var name: String = ""
    
    @Relationship(deleteRule: .cascade) var topics: [Topic] = [Topic]()
    
    init(id: UUID = UUID(), name: String = "", topics: [Topic] = [Topic]()) {
        self.id = id
        self.name = name
        self.topics = topics
    }
}

@Model
class Topic {
    var id: UUID = UUID()
    var name: String = ""
    
    init(id: UUID = UUID(), name: String = "") {
        self.id = id
        self.name = name
    }
}

struct ContentView: View {
    @Environment(\.modelContext) var modelContext
    @Query var meetings: [Meeting]
    
    @State private var path = NavigationPath()
    
    var body: some View {
        NavigationStack(path: $path) {
            
            VStack(alignment: .leading, spacing: 5) {
                
                //BUG: the list is not updated after I created a new meeting object when iCloud is activated.
                List {
                    ForEach(meetings) { meeting in
                        NavigationLink(meeting.name, value: meeting)
                    }
                }
            }
            .navigationDestination(for: Meeting.self, destination: MeetingDetailView.init)
            
            .toolbar {
                Button("add", action: createMeeting)
            }
        }
        .padding()
    }
    
    func createMeeting() {
        let m = Meeting()
        m.name = "New Meeting"
        
        modelContext.insert(m)
        path.append(m)
    }
}

struct MeetingDetailView: View {
    @Bindable var meeting: Meeting
    
    var body: some View {
        VStack(alignment: .leading, spacing: 5) {
            
            TextField("", text: $meeting.name)
        }
    }
}

Answer 1

The following code is working including iCloud synchronization and the changes I made are commented.

The App file stays unchanged.

import SwiftData
import SwiftUI
import UniformTypeIdentifiers

@Model
class Meeting {
    var id: UUID = UUID()
    var name: String = ""
    
    //the relationship is opional now and an inverse target has been added.
    @Relationship(deleteRule: .cascade, inverse: \Topic.meeting) var topics: [Topic]?
    
    init(id: UUID = UUID(), name: String = "") {
        self.id = id
        self.name = name
    }
}

@Model
class Topic {
    var id: UUID = UUID()
    var name: String = ""
    //an optionl reference has been added for the relation with a meeting object.
    var meeting: Meeting?
    
    init(id: UUID = UUID(), name: String = "", meeting: Meeting) {
        self.id = id
        self.name = name
        self.meeting = meeting
    }
}

struct ContentView: View {
    @Environment(\.modelContext) var modelContext
    @Query var meetings: [Meeting]
    
    @State private var path = NavigationPath()
    
    var body: some View {
        NavigationStack(path: $path) {
            
            VStack(alignment: .leading, spacing: 5) {
                
                List {
                    ForEach(meetings) { meeting in
                        NavigationLink(meeting.name, value: meeting)
                    }
                }
            }
            .navigationDestination(for: Meeting.self, destination: MeetingDetailView.init)
            
            .toolbar {
                Button("add", action: createMeeting)
            }
        }
        .padding()
    }
    
    func createMeeting() {
        let m = Meeting()
        m.name = "New Meeting"
        
        do {
            modelContext.insert(m)
            try modelContext.save()
            path.append(m)
        } catch {
            print(error.localizedDescription)
        }
        
    }
}

struct MeetingDetailView: View {
    @Bindable var meeting: Meeting
    
    var body: some View {
        VStack(alignment: .leading, spacing: 5) {
            
            TextField("", text: $meeting.name)
        }
    }
}