I wanted to get my SwiftData previews working in my primary project, so I started modeling them after the SampleTrips project. After messing around with that & being unable to make it work, I brought the same (working) sample code into my main project, unfortunately that's not working... I've attached the preview error (note, there's nothing in the Diagnostic Reports). //Sample code that works in it's own project, but not my primary target. import SwiftUI import SwiftData struct TestSwiftDataStuffView: View { let trip: Trip var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, \(trip.name)!") .padding() .foregroundColor(.red) } .padding() } } #Preview(traits: .sampleDataSecondary) { @Previewable @Query var trips: [Trip] TestSwiftDataStuffView(trip: trips.first!) } actor DataModelSecondary { struct TransactionAuthor { static let widget = "widget" } static let shared = DataModelSecondary() private init() {} nonisolated lazy var modelContainer: ModelContainer = { let modelContainer: ModelContainer let schema = Schema([ Trip.self ]) do { let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false, cloudKitDatabase: .none) modelContainer = try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError("Failed to create the model container: \(error)") } return modelContainer }() } @Model class Trip { @Attribute(.preserveValueOnDeletion) var name: String init(name: String) { self.name = name } } extension Trip { static var previewTrips: [Trip] { [ Trip(name: "Revenant"), Trip(name: "Newcastle"), Trip(name: "Bianca") ] } } struct SampleDataSecondary: PreviewModifier { static func makeSharedContext() throws -> ModelContainer { let config = ModelConfiguration(isStoredInMemoryOnly: true) let container = try ModelContainer( for: Trip.self, configurations: config ) SampleDataSecondary.createSampleData(into: container.mainContext) return container } func body(content: Content, context: ModelContainer) -> some View { content.modelContainer(context) } static func createSampleData(into modelContext: ModelContext) { Task { @MainActor in let sampleDataTrips: [Trip] = Trip.previewTrips let sampleData: [any PersistentModel] = sampleDataTrips //+ sampleDataLA + sampleDataBLT sampleData.forEach { modelContext.insert($0) } try? modelContext.save() } } } @available(iOS 18.0, *) extension PreviewTrait where T == Preview.ViewTraits { @MainActor static var sampleDataSecondary: Self = .modifier(SampleDataSecondary()) } Xcode16Preview.txt

I have created a minimum example to demonstrate an issue with observing SwiftData model and UndoManager. This project includes a simple NavigationSplitView, an Item SwiftData model that is being persisted and an enabled UndoManager. Problem: The SwiftData model Item can be observed as expected. Changing the date in the DetailView works as expected and all related views (ListElementView + DetailView) are updated as expected. When pressing ⌘+Z to undo with the enabled UndoManager, deletions or inserts in the sidebar are visible immediately (and properly observed by ContentView). However, when changing the timestamp and pressing ⌘+Z to undo that change, it is not properly observed and immediately updated in the related views (ListElementView + DetailView). Further comments: Undo operation to the model value changes (here: timestamp) are visible in the DetailView when changing sidebar selections Undo operation to the model value changes (here: timestamp) are visible in the ListElementView when restarting the app Undo operation to the model value changes (here: timestamp) are are properly observed and immediately visible in the sidebar, when ommiting the ListElementView (no view encapsulation) Relevant code base: struct ContentView: View { @Environment(\.modelContext) private var modelContext @Query private var items: [Item] @State private var selectedItems: Set<Item> = [] var body: some View { NavigationSplitView { List(selection: $selectedItems) { ForEach(items) { item in ListElementView(item: item) .tag(item) } .onDelete(perform: deleteItems) } .navigationSplitViewColumnWidth(min: 180, ideal: 200) .toolbar { ToolbarItem { Button(action: addItem) { Label("Add Item", systemImage: "plus") } } } } detail: { if let item = selectedItems.first { DetailView(item: item) } else { Text("Select an item") } } .onDeleteCommand { deleteSelectedItems() } } private func addItem() { withAnimation { let newItem = Item(timestamp: Date()) modelContext.insert(newItem) } } private func deleteItems(offsets: IndexSet) { withAnimation { for index in offsets { modelContext.delete(items[index]) } } } private func deleteSelectedItems() { for selectedItem in selectedItems { modelContext.delete(selectedItem) selectedItems.remove(selectedItem) } } } struct ListElementView: View { @Bindable var item: Item var body: some View { Text("Item at \(item.timestamp, format: Date.FormatStyle(date: .numeric, time: .standard))") } } struct DetailView: View { @Bindable var item: Item var body: some View { Text(item.timestamp, format: Date.FormatStyle(date: .numeric, time: .standard)) DatePicker(selection: $item.timestamp, label: { Text("Change Date:") }) } } @Model final class Item { var timestamp: Date init(timestamp: Date) { self.timestamp = timestamp } } It seems that the UndoManager does not trigger a redraw of the ContentView through the items query? Is this a bug or a feature?

.modelContainer(for: MyMode.self, isUndoEnabled: true) This may work for single model containers, but I have a number of models. I don't see how to enable undo for multiple model containers.

Hello, I have a SwiftUI view with the following state variable: @State private var startDate: Date = Date() @State private var endDate: Date = Date() @State private var client: Client? = nil @State private var project: Project? = nil @State private var service: Service? = nil @State private var billable: Bool = false Client, Project, and Service are all SwiftData models. I have some view content that binds to these values, including Pickers for the client/project/service and a DatePicker for the Dates. I have an onAppear listener: .onAppear { switch state.mode { case .editing(let tt): Task { await MainActor.run { startDate = tt.startDate endDate = tt.endDate client = tt.client project = tt.project service = tt.service billable = tt.billable } } default: return } } This works as expected. However, if I remove the Task & MainActor.run, the values do not fully update. The DatePickers show the current date, the Pickers show a new value but tapping on them shows a nil default value. What is also extremely strange is that if tt.billable is true, then the view does update as expected. I am using Xcode 15.4 on iOS simulator 17.5. Any help would be appreciated.

The SwiftData predicate documentation says that it supports the contains(where:) sequence operation in addition to the contains(_:) string comparison but when I put them together in a predicate to try and perform a tokenised search I get a runtime error. Unsupported subquery collection expression type (NSInvalidArgumentException) I need to be able to search for items that contain at least one of the search tokens, this functionality is critical to my app. Any suggestions are appreciated. Also does anyone with experience with CoreData know if this is possible to do in CoreData with NSPredicate? import SwiftData @Model final class Item { var textString: String = "" init() {} } func search(tokens: Set<String>, context: ModelContext) throws -> [Item] { let predicate: Predicate<Item> = #Predicate { item in tokens.contains { token in item.textString.contains(token) } } let descriptor = FetchDescriptor(predicate: predicate) return try context.fetch(descriptor) }

I am unsure the correct way to model my data. I have a swift data object and then some referenced objects. Is there ever a reason those should just be structs or should they always be swift data objects themselves? for example right now this is what I'm doing: @Model final class Exam { var timestamp: Date @Attribute(.unique) var examID: UUID var title: String var questions: [Question] ... } and Question is struct Question: Codable, Identifiable { var id: UUID var number: Int var points: Int var prompt: String var answer: String } is there any problem with this or should I not be using a Struct for Question and instead use another Swift Data object with @Relationship ? I thought since its a simple object just using a struct would be fine, however... when I create a new Question object, it seems to create SwiftUI retain cycles with the warning === AttributeGraph: cycle detected through attribute 633984 === in the terminal for example, Button("Add Question", systemImage: "questionmark.diamond") { let newQuestion = Question(id: UUID(), number: exam.questions.count+1, points: 1, prompt: "", answer: "", type: .multipleChoice) exam.questions.append(newQuestion) } So, is it ok to mix structs with swift data objects or is it not best practice? And is this causing the SwiftUI retain cycles or are the issues unrelated?

I have two versionedSchema V1VersionedSchema, V2VersionedSchema. When i create schema with versionedSchema like code below and check version using breakpoint, V1, V2 Schema encodingVersion is same. let v3Schema = Schema(versionedSchema: V1VersionedSchema.self) // encodingVersion: 1.0.0 // schemaEncodingVersion: 1.0.0 let v2Schema = Schema(versionedSchema: V2VersionedSchema.self) // encodingVersion: 1.0.0 // schemaEncodingVersion: 2.0.0 Why encoding version is same? (I think migration plan v1 to v2 isn't work becaus of that)

Hello By default if swiftData is unable to open a file on mac (due to it being the wrong format, or an old model) the app hard crashes (macOS 14.4.1) - is there a way to catch this problem and present a message to the user, rather than the app simply crashing The whole way that swiftData opens files etc is very opaque so I'm not clear how we can wrap things in a nice way Thanks Richard

The exact error is: Unable to create bundle at URL (file:///System/Library/CoreServices/SystemVersion.bundle): does not exist or not a directory (0).

I am creating an app, and on the app, the user can select something like, let's say, their workplace, while creating their account. I want to append the workplace data to a model without the use of UI, so that I can display the workplace names that the user can choose from. How do I append the data to the model?

Hello, I have been working on SwiftData since a month now and i found very weird that every time i update a data inside a SwiftData model my app became very slow. I used the instrument if something was wrong, and i see memory increasing without releasing. My app have a list with check and unchecked elements (screeshot below). I just press check and unchecked 15 times and my memory start from 149mb to 361mb (screenshots below). For the code i have this model. final class Milestone: Identifiable { // ********************************************************************* // MARK: - Properties @Transient var id = UUID() @Attribute(.unique) var uuid: UUID var text: String var goalId: UUID var isFinish: Bool var createdAt: Date var updatedAt: Date var goal: Goal? init(from todoTaskResponse: TodoTaskResponse) { self.uuid = todoTaskResponse.id self.text = todoTaskResponse.text self.goalId = todoTaskResponse.goalId self.isFinish = todoTaskResponse.isFinish self.createdAt = todoTaskResponse.createdAt self.updatedAt = todoTaskResponse.updatedAt } init(uuid: UUID, text: String, goalId: UUID, isFinish: Bool, createdAt: Date, updatedAt: Date, goal: Goal? = nil) { self.uuid = uuid self.text = text self.goalId = goalId self.isFinish = isFinish self.createdAt = createdAt self.updatedAt = updatedAt self.goal = goal } } For the list i have var milestonesView: some View { ForEach(milestones) { milestone in MilestoneRowView(task: milestone) { milestone.isFinish.toggle() } .listRowBackground(Color.backgroundComponent) } .onDelete(perform: deleteMilestone) } And this is the cell struct MilestoneRowView: View { // ********************************************************************* // MARK: - Properties var task: Milestone var action: () -> Void init(task: Milestone, action: @escaping () -> Void) { self.task = task self.action = action } var body: some View { Button { action() } label: { HStack(alignment: .center, spacing: 8) { Image(systemName: task.isFinish ? "checkmark.circle.fill" : "circle") .font(.title2) .padding(3) .contentShape(.rect) .foregroundStyle(task.isFinish ? .gray : .primary) .contentTransition(.symbolEffect(.replace)) Text(task.text) .strikethrough(task.isFinish) .foregroundStyle(task.isFinish ? .gray : .primary) } .foregroundStyle(Color.backgroundComponent) } .animation(.snappy, value: task.isFinish) } } Does someone have a idea? Thanks

I'm currently using Xcode 16 Beta (16A5171c) and I'm getting a crash whenever I attempt to fetch using my ModelContext in my SwiftUI video using the environment I'm getting a crash specifically on iOS 18 simulators. I've opened up a feedback FB13831520 but it's worth noting that I can run the code I'll explain in detail below on iOS 17+ simulator and devices just fine. I'm getting the following crash: *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'The specified URI is not a valid Core Data URI: x-coredata:///MyApp/XXXXX-XXXXX-XXXX-XXXX-XXXXXXXXXXXX' It's almost as if on iOS18 SwiftData is unable to find the file on the simulator to perform CRUD operations. All I'm doing in my project is simply fetching data using the modelContext. func contains(_ model: MyModel, in context: ModelContext) -> Bool { let objId = palette.persistentModelID let fetchDesc = FetchDescriptor<MyModel>(predicate: #Predicate { $0.persistentModelID == objId }) let itemCount = try? context.fetchCount(fetchDesc) return itemCount != 0 }

I'm distributing an iOS (17.4+) and visionOS (1.2+) app via TestFlight that's using SwiftData. The most common crash by far is from SwiftData when deleting models from a context using a predicate (first snippet below), but so far I've been unable to reproduce it myself locally (second snippet below). I'm using SwiftData outside of SwiftUI views, via my own wrapper, and converting between my app models and SwiftData models. Does anyone have any ideas how I could potentially narrow this issue down (or reproduce), or know of any similar issues? Thanks! — Seb do { try context.transaction { context in let predicate = #Predicate<PersistedFeed> { $0.id == id } do { try context.delete(model: PersistedFeed.self, where: predicate) } catch { // .. Omitted for brevity } } } catch { // .. Omitted for brevity } Crash: Thread 0 Crashed: 0 libswiftCore.dylib 0x000000018dd558c0 _assertionFailure(_:_:file:line:flags:) + 264 (AssertCommon.swift:144) 1 SwiftData 0x000000022f7f323c static PersistentModel.keyPathToString(keypath:) + 1496 (DataUtilities.swift:0) 2 SwiftData 0x000000022f83312c PredicateExpressions.KeyPath.convert(state:) + 492 (FetchDescriptor.swift:394) 3 SwiftData 0x000000022f834a24 protocol witness for ConvertibleExpression.convert(state:) in conformance PredicateExpressions.KeyPath<A, B> + 16 (<compiler-generated>:0) 4 SwiftData 0x000000022f830a70 PredicateExpression.convertToExpressionOrPredicate(state:) + 724 (FetchDescriptor.swift:203) 5 SwiftData 0x000000022f831874 PredicateExpression.convertToExpression(state:) + 36 (FetchDescriptor.swift:217) 6 SwiftData 0x000000022f83b6c8 PredicateExpressions.Equal.convert(state:) + 328 7 SwiftData 0x000000022f8360ec protocol witness for ConvertibleExpression.convert(state:) in conformance PredicateExpressions.Equal<A, B> + 64 (<compiler-generated>:0) 8 SwiftData 0x000000022f830a70 PredicateExpression.convertToExpressionOrPredicate(state:) + 724 (FetchDescriptor.swift:203) 9 SwiftData 0x000000022f82fd60 PredicateExpression.convertToPredicate(state:) + 28 (FetchDescriptor.swift:224) 10 SwiftData 0x000000022f82edb4 nsPredicate<A>(for:) + 956 (FetchDescriptor.swift:88) 11 SwiftData 0x000000022f807c2c ModelContext.delete<A>(model:where:includeSubclasses:) + 596 (ModelContext.swift:1846) 12 SwiftData 0x000000022f81994c dispatch thunk of ModelContext.delete<A>(model:where:includeSubclasses:) + 56

Hello I'm a new developer and am learning the ropes. I have an app that I'm testing and seem to have run into a bug. The data is syncing from one device to another, however it takes closing the app on the Mac or force closing the app on iOS/iPadOS to get the app to reflect the new data. Is there specific code I code share to help solve this issue or any suggestions that someone may have? Thank you ahead of time for your assistance. import SwiftData @main struct ApplicantProcessorApp: App { var sharedModelContainer: ModelContainer = { let schema = Schema([ Applicant.self, ]) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { return try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError("Could not create ModelContainer: \(error)") } }() var body: some Scene { WindowGroup { ContentView() } .modelContainer(sharedModelContainer) } } struct ContentView: View { var body: some View { FilteredApplicantListView() } } #Preview { ContentView() .modelContainer(SampleData.shared.modelContainer) } struct FilteredApplicantListView: View { @State private var searchText = "" var body: some View { NavigationSplitView { ApplicantListView(applicantFilter: searchText) .searchable(text: $searchText, prompt: "Enter Name, Email, or Phone Number") .autocorrectionDisabled(true) } detail: { } } } import SwiftData struct ApplicantListView: View { @Environment(\.modelContext) private var modelContext @Query private var applicants: [Applicant] @State private var newApplicant: Applicant? init(applicantFilter: String = "") { // Filters } var body: some View { Group { if !applicants.isEmpty { List { ForEach(applicants) { applicant in NavigationLink { ApplicantView(applicant: applicant) } label: { HStack { VStack { HStack { Text(applicant.name) Spacer() } HStack { Text(applicant.phoneNumber) .font(.caption) Spacer() } HStack { Text(applicant.email) .font(.caption) Spacer() } HStack { Text("Expires: \(formattedDate(applicant.expirationDate))") .font(.caption) Spacer() } } if applicant.applicationStatus == ApplicationStatus.approved { Image(systemName: "checkmark.circle") .foregroundStyle(.green) .font(.title) } else if applicant.applicationStatus == ApplicationStatus.declined { Image(systemName: "xmark.circle") .foregroundStyle(.red) .font(.title) } else if applicant.applicationStatus == ApplicationStatus.inProgress { Image(systemName: "hourglass.circle") .foregroundStyle(.yellow) .font(.title) } else if applicant.applicationStatus == ApplicationStatus.waitingForApplicant { Image(systemName: "person.circle") .foregroundStyle(.yellow) .font(.title) } else { Image(systemName: "yieldsign") .foregroundStyle(.yellow) .font(.title) } } } } .onDelete(perform: deleteItems) } } else { ContentUnavailableView { Label("No Applicants", systemImage: "pencil.fill") } } } .navigationTitle("Applicants") .toolbar { ToolbarItem(placement: .navigationBarTrailing) { EditButton() } ToolbarItem { Button(action: addApplicant) { Label("Add Item", systemImage: "plus") } } } .sheet(item: $newApplicant) { applicant in NavigationStack { ApplicantView(applicant: applicant, isNew: true) } } } private func addApplicant() { withAnimation { let newItem = Applicant() modelContext.insert(newItem) newApplicant = newItem } } private func deleteItems(offsets: IndexSet) { withAnimation { for index in offsets { modelContext.delete(applicants[index]) } } } func formattedDate(_ date: Date) -> String { let dateFormatter = DateFormatter() dateFormatter.dateStyle = .short dateFormatter.timeStyle = .none return dateFormatter.string(from: date) } } import SwiftData @Model final class Applicant { var name = "" var email = "" var phoneNumber = "" var applicationDate = Date.now var expirationDate: Date { return Calendar.current.date(byAdding: .day, value: 90, to: applicationDate)! }

Hi, I am inserting two models where the "unique" attribute is the same. I was under the impression, that this should result in an upsert and not two inserts of the model, but that is not the case. See the test coding below for what I am doing (it is self contained, so if you want to try it out, just copy it into a test target). The last #expect statement fails because of the two inserts. Not sure if this is a bug (Xcode 16 beta 2 on Sonoma running an iOS 18 simulator) or if I am missing something here... // MARK: - UniqueItem - @Model final class UniqueItem { #Unique<UniqueItem>([\.no]) var timestamp = Date() var title: String var changed = false var no: Int init(title: String, no: Int) { self.title = title self.no = no } } // MARK: - InsertTests - @Suite("Insert Tests", .serialized) struct InsertTests { var sharedModelContainer: ModelContainer = { let schema = Schema([ UniqueItem.self, ]) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { return try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError("Could not create ModelContainer: \(error)") } }() @Test("Test unique.") @MainActor func upsertAndModify() async throws { let ctx = sharedModelContainer.mainContext try ctx.delete(model: UniqueItem.self) let item = UniqueItem(title: "Item \(1)", no: 0) ctx.insert(item) let allFD = FetchDescriptor<UniqueItem>() let count = try ctx.fetchCount(allFD) #expect(count == 1) let updatedItem = UniqueItem(title: "Item \(1)", no: 0) updatedItem.changed = true ctx.insert(updatedItem) // we should still have only 1 item because of the unique constraint let allCount = try ctx.fetchCount(allFD) #expect(allCount == 1) } }

Hi, I'm updating my app from CoreData to SwiftData and came across an issue. My app has multiple users so in CoreData and I assigned each a myID value set to an UUID so I could use UserDefaults to set the preferred user on app load. When switching over I noticed the PersistentIdentifier value and got excited as I could fetch the matching entity with modelContext.model(for: yourID). I decided to use that instead so I updated my UserDefaults code from UUID to this: @Published var selectedUserID: PersistentIdentifier? { didSet { UserDefaults.standard.set(selectedUserID, forKey: "selectedUserID") } } init() { self.selectedUserID = UserDefaults.standard.object(forKey: "selectedUserID") as? PersistentIdentifier ?? nil } This code compiles and, of course the id is currently set to nil. My issue now is when I try to assign a user to it ar my app crashes and I get the following error: Attempt to set a non-property-list object SwiftData.PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(url: x-coredata://6FE80FC9-0B4C-491E-8093-DED37A619F1B/EnteredUser/p834), implementation: SwiftData.PersistentIdentifierImplementation) as an NSUserDefaults/CFPreferences value for key selectedUserID Should I go back to an additional UUID field in my user model and find it that way or is there a way to use the PersistentIdentifier value with my UserDefaults? Thanks for any tips.

There are multiple versions of VersionedSchema in my App. I used MigrationPlan to migrate data. It works well in Xcode, but in TestFlight and App Store, it always crashes when opening the App for the first time. MeMigrationPlan Code: import Foundation import SwiftData enum MeMigrationPlan: SchemaMigrationPlan { static var schemas: [any VersionedSchema.Type] { [MeSchemaV1.self, MeSchemaV2.self, MeSchemaV3.self, MeSchemaV4.self] } static var stages: [MigrationStage] { [migrateV1toV2, migrateV2toV3, migrateV3toV4] } //migrateV1toV2, because the type of a data field in MeSchemaV1.TodayRingData.self is modified, the historical data is deleted during migration, and the migration work is successfully completed. static let migrateV1toV2 = MigrationStage.custom( fromVersion: MeSchemaV1.self, toVersion: MeSchemaV2.self, willMigrate: { context in try context.delete(model: MeSchemaV1.TodayRingData.self) }, didMigrate: nil ) //migrateV2toV3, because a new Model was added, it would crash when starting up when TF and the official version were updated, so I tried to delete the historical data during migration, but the problem still exists. static let migrateV2toV3 = MigrationStage.custom( fromVersion: MeSchemaV2.self, toVersion: MeSchemaV3.self, willMigrate: { context in try context.delete(model: MeSchemaV2.TodayRingData.self) try context.delete(model: MeSchemaV2.HealthDataStatistics.self) try context.delete(model: MeSchemaV2.SportsDataStatistics.self) try context.delete(model: MeSchemaV2.UserSettingTypeFor.self) try context.delete(model: MeSchemaV2.TodayRingData.self) try context.delete(model: MeSchemaV2.TodayHealthData.self) try context.delete(model: MeSchemaV2.SleepDataSource.self) try context.delete(model: MeSchemaV2.WorkoutTargetData.self) try context.delete(model: MeSchemaV2.WorkoutStatisticsForTarget.self) try context.delete(model: MeSchemaV2.HealthDataList.self) }, didMigrate: nil ) //migrateV3toV4, adds some fields in MeSchemaV3.WorkoutList.self, and adds several new Models. When TF and the official version are updated, it will crash at startup. Continue to try to delete historical data during migration, but the problem still exists. static let migrateV3toV4 = MigrationStage.custom( fromVersion: MeSchemaV3.self, toVersion: MeSchemaV4.self, willMigrate: { context in do { try context.delete(model: MeSchemaV3.WorkoutList.self) try context.delete(model: MeSchemaV3.HealthDataStatistics.self) try context.delete(model: MeSchemaV3.SportsDataStatistics.self) try context.delete(model: MeSchemaV3.UserSettingTypeFor.self) try context.delete(model: MeSchemaV3.TodayRingData.self) try context.delete(model: MeSchemaV3.TodayHealthData.self) try context.delete(model: MeSchemaV3.SleepDataSource.self) try context.delete(model: MeSchemaV3.WorkoutTargetData.self) try context.delete(model: MeSchemaV3.WorkoutStatisticsForTarget.self) try context.delete(model: MeSchemaV3.HealthDataList.self) try context.delete(model: MeSchemaV3.SleepStagesData.self) try context.save() } catch { print("Migration from V3 to V4 failed with error: \(error)") throw error } }, didMigrate: nil ) }

Hi all, I have done a lot of research on this but am not able to come up with a workable solution. Background: I am trying to make an universal app on macOS/iOS that organizes media (image/video/pdf); think of its functionality like Apple's Photos app. So for my app document type, I would have my custom file package and within the package folder, there would be a SwiftData model container file and folders to hold user media. Approaches taken: DocumentGroup with SwiftData model then write directly into the file package In my App scene, I create document by having DocumentGroup(editing: .customDocument, migrationPlan: CustomMigrationPlan.self). This will create a document with a model container with my SwiftData model. And when I need to add media files into the document, I get the URL of the document, then use FileManager to write the file into the desired folder in the document. The result is that the media file is saved in the file package but then the SwiftData container is corrupted (all model data is reset to empty.) I am now trying to: 2. DocumentGroup with custom file package then try to embed SwiftData container In my current approach, I would create a document by having DocumentGroup(newDocument: CustomFileDocument()). I have custom FileDocument and FileWrapper. But the problem is I don't know how to embed a SwiftData container into my FileDocument. Is it possible to create a SwiftData model container when my FilerWrapper initialize? I can't figure out how to do this. Can anyone please advice on how I should accomplish this? Or if maybe I am looking at this problem wrongly? Do I need to use AppKit/UIKit with Core Data because it's currently not possible with SwiftUI/SwiftData? Thank you so much for reading and any input is greatly appreciated.

I had a series of @Model classes with some mandatory attributes and some optional. Pre-move to 18, everything was working fine. After the migration, it reports that every single non-Optional attribute is nil upon trying to save. The error is CoreData related but not sure if its in the Core layer or Swift layer. Sample error (with app data removed) is : SwiftData.DefaultStore save failed with error: Error Domain=NSCocoaErrorDomain Code=1560 "Multiple validation errors occurred." Error Domain=NSCocoaErrorDomain Code=1570 \"%{PROPERTY}@ is a required value.\" UserInfo={NSValidationErrorObject=<NSManagedObject: 0x30388b2a0> NSLocalizedDescription=%{PROPERTY}@ is a required value., NSValidationErrorKey=systemName, NSValidationErrorValue=null}" I have modified the code to provide default values for all constructors in an attempt to see a difference, but get the same errors

When user triggers a sheet of a view, it's quite easy to deal with its confirmation action. However, how can I deal with the cancellation action, which means when user taps the cancel button, what they edits can re-become its original version ( I am using SwiftData)?