Hello everyone, I hope you are well. I have a question about .environment. I have an observable viewModel which has some functions and publishing value. I'm observing this viewModel in only 2 views but I'm using viewModel functions in every view. Should I use it (.environment). if I should use it, should I use this environment macro (@Environment(ViewModel.Self) var vm) for only functions in view? Thank you so much.

I am targeting iOS17 and using @Observable. I have an array of items, and I want to present a sheet when the array is greater than zero. My @Observable looks like this: @Observable class BStoreOO { var items: [Int] = [] var showBS: Bool { items.isEmpty } func updateItems(newItems: [Int]) { self.items = newItems } } When this array gets added to, from another view, I would like to present a sheet/popover. Inside my ContentView I have a @State `... that uses that @Observable struct ContentView: View { @State var bStore = BStoreOO() Further down in my View, how should I toggle this view on the basis of the observed array not being empty? I have tried a number of ways. Some error, some don't, but none present the sheet! For example: .popover(isPresented: bStore.showBS) { PopoverContent() } Gives the error "Cannot convert value of type 'Bool' to expected argument type 'Binding'" If I add a State like this: @State private var isShowingBS = false and then add this: .onChange(of: bStore.items) { self.isShowingBS = self.bStore.items.count > 0 } I don't get errors but nothing is presented. What is the correct way to bind the presentation of the sheet to whether the observed items array is empty or not?

Using SwiftUI, the timecode (seconds notation) has been referenced using ObservableObject as follows. In this case, the timecode values were reflected in Text in real time without any problem. struct ContentView: View { . . . var body: some View { NavigationStack { // Time Code Text Text(String(format:"%02d:%02d:%02d", sMinute, sSecond, sMsec)) .font(Font(UIFont.monospacedDigitSystemFont(ofSize: 30.0, weight: .regular))) class ViewModel: ObservableObject { // Time Code "%02d:%02d:%02d" @Published var sMinute = 0 @Published var sSecond = 0 @Published var sMsec = 0 When I changed it to @Observable class as follows, the timecode operation is stopped and the values are updated only when the operation is finished. @Observable class ViewModel { // Time Code "%02d:%02d:%02d" var sMinute = 0 var sSecond = 0 var sMsec = 0 Is it possible to do something with the @Observable class that would allow it to be constantly monitored and updated in real time? Or should we change it back? If we have a history of changing to @Observable in relation to other functions, and we have no choice but to revert back, is this where we need to make a change that would keep it functional separately?

Using SwiftData I have one relatively short list of @Model class objects that are referenced in several views. I thought it would be handy to query once and share via the environment but my Table in other views does not update when data changes as it does when I repeat the Query in each view. Is this a bad idea or perhaps I implemented it improperly? @Observable class AllAccounts: ObservableObject { var accounts: [Account] = [] } struct ContentView: View { @Environment(\.modelContext) private var modelContext // an instance of the AllAccounts class, will save Query results to all.accounts @StateObject var all = AllAccounts() // one query for all accounts once in app, store in the environment` @Query private var allAccounts: [Account] .onAppear { all.accounts = allAccounts } .environment(all)

Hello, I can't seem to set any breakpoint in didSet for all properties inside Observable. Is this a bug? XcodeVersion 15.2 (15C500b) Thanks!

Hey there i try to adept the Observable macro for my SwiftUI Project. I wanna get data from HealthKit and transform it to FHIR. Here i need one class for managing this process which will be shared through my project in order to access these data. The following Codesnippet raises an error: import Observation import HealthKit import FHIR @Observable class HealthKitManager{ let healthStore = HKHealthStore() init(){ } func requestAuthorization(){ let authTypes: Set = [HKQuantityType(.stepCount), HKQuantityType(.heartRate) ] guard HKHealthStore.isHealthDataAvailable() else { print("health data not available!") return } healthStore.requestAuthorization(toShare: nil, read: authTypes) { success, error in if success { print("OK Fetching") } else { print("\(String(describing: error))") } } } } So the FHIR module contains a Models module which define different models. In the FHIR world there is also a concept called observation... now the problems begin. open class Observation : Models.DomainResource { ... } When i try import Observation for the Observable macro and also import FHIR in order to create Observations, XCode rises an error: Observable' is not a member type of class 'Models.Observation' It's also said that Observation is declared in the FHIR.Models.Observation class which is true, but it seems that this raises the Problem with the @Observable macro. It's also said that Type 'Observation' has no member 'ObservationRegistrar' Which comes from the Observable Macro i think. When i don't import FHIR then everything works fine, but then my use case is broken because i need these standard in order to get my use case running. All in all i need big help and be thankfull for possible solutions!

I've just started tinkering with @Observable and have run into a question... What is the best practice for observing an Observable object outside of SwiftUI? For example: @Observable class CountingService { public var count: Int = 0 } @Observable class ObservableViewModel { public var service: CountingService init(service: CountingService) { self.service = service // how to bind to value changes on service? } // suggestion I've seen that doesn't smell right func checkCount() { _ = withObservationTracking { service.count } onChange: { DispatchQueue.main.async { print("count: \(service.count)") checkCount() } } } } Historically using ObservableObject I'd have used Combine to monitor changes to service. That doesn't seem possible with @Observable and I don't know that I've come across an accepted / elegant solution? Perhaps there isn't one? There's no particular reason that CountingService has to be @Observable -- it's just nice and clean. Any suggestions would be appreciated!

in the SampleTrips, for the pure SwiftData version, when I add a living accommodation from the trip detail view, the trip detail view won’t update until I go back to the trip list view and enter again. why didn’t the trip detail view update? I have tested the pure CoreData version in sample code, it worked well. is this a bug or a feature of SwiftData?

I am using the Observable macro and when I use @Environment property wrapper to instance my model the preview stop working. Sample code below my model Library import SwiftUI import Observation @Observable class Library { // ... } Now in my main app I created an instance of Library and add that instance to the environment @main struct BookReaderApp: App { @State private var library = Library() var body: some Scene { WindowGroup { LibraryView() .environment(library) } } } Now if I want to retrieve the Library instance from any view using the @Environment property wrapper the preview stop working completely struct LibraryView: View { @Environment(Library.self) private var library var body: some View { List(library.books) { book in BookView(book: book) } } } #Preview { LibraryView() } Check the 2 screenshots below Any idea why this is happening? Is there any workaround? I am working with Xcode Version 15.2. Thanks in advance for any kind of help!

I get this error while migrating from ObservableObject to @Observable. Call to main actor-isolated initializer 'init()' in a synchronous nonisolated context My original code: struct SomeView: View { @StateObject private var viewModel = ViewModel() } After migration: @MainActor @Observable class BaseViewModel { } @MainActor class ViewModel: BaseViewModel { } struct SomeView: View { @State private var viewModel = ViewModel() } As discussed here. It seems like @StateObject is adding @MainActor compliance to my View under the hood because it's wrappedValue and projectedValue properties are marked as @MainActor, while on @State they are not. @available(iOS 14.0, macOS 11.0, tvOS 14.0, watchOS 7.0, *) @frozen @propertyWrapper public struct StateObject<ObjectType> : DynamicProperty where ObjectType : ObservableObject { ... @MainActor public var wrappedValue: ObjectType { get } .... @MainActor public var projectedValue: ObservedObject<ObjectType>.Wrapper { get } } One solution for this is to mark my View explicitly as @MainActor struct ViewModel: View but it have it side effects, for example code like: Button(action: resendButtonAction) { Text(resendButtonAttributedTitle()) } Will result a warning Converting function value of type '@MainActor () -> ()' to '() -> Void' loses global actor 'MainActor' While could be easily solved by using instead Button(action: { resendButtonAction() } ) { Text(resendButtonAttributedTitle()) } I still feel like marking the whole View explicitly as @MainActor is not a good practice. Adding fake @StateObject property to my view also do the trick, but it's a hack (the same for @FetchRequest). Can anyone think of a more robust solution for this?

I am new to programing apps, and I am trying to figure out how to use one item out of an array of items in a Text line. I am not getting any complaints from Xcode, but then the preview crashes giving me a huge error report that it keeps sending to Apple. I have cut out all the extra stuff from the app to get just the basics. What I want it to print on the screed is "Hello Bill How are you?" with Bill being from the observable array. The first picture below is about 2 seconds after I removed the // from in front of the line that reads Text("(friend2.friend2[1].name)"). The other two pictures are the main app page and the page where I setup the array. At the very bottom is a text file of the huge report it kept sending to Apple, until I turned of the option of sending to Apple. Would someone please explain what I am doing wrong. Well a side from probably everything. Error code.txt

I am working on a app that uses the new Observation framework and MVVM design pattern. I have a view composed of a list and a header that shows statistics about the displayed content by using an Observable ViewModel. When I add new contents, it is added to the list but the header seems to not take it into account even if its init method and body property are called. @Observable final class ViewModel { let contents: [String] init(contents: [String]) { self.contents = contents print("ViewModel init") } deinit { print("ViewModel deinit") } } struct ContentHeaderView: View { @State private var viewModel: ViewModel init(contents: [String]) { self._viewModel = State( initialValue: ViewModel(contents: contents) ) } var body: some View { Text("\(self.viewModel.contents.count)") } } struct ContentListView: View { @State private var contents = ["Content 1"] var body: some View { NavigationStack { VStack { ContentHeaderView(contents: self.contents) List(self.contents, id: \.self) { content in Text(content) } } .toolbar { ToolbarItem { Button("Add Content") { let newContent = "New Content \(self.contents.count + 1)" self.contents.append(newContent) } } } } } } In this example, when I tap the "Add Content" toolbar button, the header view that's supposed to show the number of content still display "1" even if the array now contains 2 elements. I added print statements to show that a new ViewModel is created every time the view is updated and the currently displayed view still uses the first created ViewModel which in fact contains a array with only one element. ContentHeaderView Init // on appear ContentHeaderView Init // First button tap // Every other tap ContentHeaderView Init ContentHeaderView Deinit I've read the threads 736239 and 736110 that discusses about similar issues when presenting sheets. I have similar code without issues since it's been fixed in iOS 17.2 beta 1 but it seems to still happen on view updates. Can you please confirm that this is an issue with the Observable framework and State properties or is there something I'm doing wrong ? Thanks

after i import swiftui, there's no @observable?? it shows unknown attribute... and i cant import observation or swiftdata import Foundation import SwiftUI @Observable class BusinessModel{ var businesses = [Business]() var selectedBusiness: Business? var input: String = "" var service = dataservice() }

I am learning SwiftUI. Error: SwiftUI/Environment+Objects.swift:32: Fatal error: No Observable object of type ViewModel found. A View.environmentObject(_:) for ViewModel may be missing as an ancestor of this view. I do not get the point why this happens. The error is shown in the line : "renderer.render {... import SwiftData import SwiftUI @Observable class ViewModel { var groupNumber: String = "Gruppe" var sumOfHours: Int = 0 var personsToPrint: [Person]? = nil @MainActor func pdfReport(person: [Person]) { if personsToPrint != nil { for person in personsToPrint! { let renderer = ImageRenderer(content: PersonDetailView(person: person)) let url = URL.documentsDirectory.appending(path: "\(person.lastname) \(person.firstname).pdf") print(person.lastname, person.firstname) renderer.render { size, context in var box = CGRect(x: 0, y: 0, width: size.width, height: size.height) guard let pdf = CGContext(url as CFURL, mediaBox: &box, nil) else { return } pdf.beginPDFPage(nil) context(pdf) pdf.endPDFPage() pdf.closePDF() let data = try! Data(contentsOf: url) //pdf muss erst in Daten umgewandelt werden. do { try data.write(to: url) print("Daten wurden hier gespeichert: \(url)") } catch { print("PDF could not be saved!") } } } } } }

Following this Apple Article, I copied their code over for observePlayingState(). The only difference I am using @Observable instead of ObservableObject and @Published for var isPlaying. We get a bit more insight after removing the $ symbol, leading to a more telling error of: Cannot convert value of type 'Bool' to expected argument type 'Published.Publisher' Is there anyway to get this working with @Observable?

I am following this Apple Article on how to setup an AVPlayer. The only difference is I am using @Observable instead of an ObservableObject with @Published vars. Using @Observable results in the following error: Cannot find '$isPlaying' in scope If I remove the "$" symbol I get a bit more insight: Cannot convert value of type 'Bool' to expected argument type 'Published<Bool>.Publisher' If I change by class to an OO, it works fine, although, is there anyway to get this to work with @Observable?

I am surprised at what I am seeing with the new @Observable framework in iOS 17. It seems that if the view containing the @State var, ie viewModel, is modified, then the init of that viewModel will also be called. This is not the behavior of the prior StateObject method of using a viewModel. As I understand the @State should not be reinitialized on redrawing on the View, is this the expected behavior? Example: struct ContentView: View { @State var offset = false var body: some View { VStack { InnerView() .offset(x: offset ? 200 : 0) Button("Offset") { offset.toggle() } } } } // iOS 17 Observable method: struct InnerView: View { @State var viewModel: ViewModel init() { self._viewModel = State(wrappedValue: ViewModel()) } var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, world!") } .padding() } } @Observable class ViewModel { init() { print("ViewModel Init") } } // StateObject method: struct InnerView: View { @StateObject var viewModel: ViewModel init() { self._viewModel = StateObject(wrappedValue: ViewModel()) } var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, world!") } .padding() } } class ViewModel: ObservableObject { init() { print("ViewModel Init") } }

Hi guys, I am trying to use the new @Observable macro. According to the documentation, this new macro will automatically generate observable properties, but I am having issues using my properties when Bindings are necessary. Previously I had a setup like this: class Example: ObservableObject { @Published public var myArray = [CustomType]() } I initialised one instance of the Example-class in @main @StateObject private var exampleClass = Example() And added as an .environmentObject onto the root view ContentView() .environmentObject(exampleClass) In child views I was able to access the @Published property as a binding via @EnvironmentObject private var example: Example $example.myArray What I am trying now This is the setup that I am trying with now: @Observable class Example { public var myArray = [CustomType]() } State instead of StateObject in @main @State private var exampleClass = Example() .environment instead of .environmentObject ContentView() .environmentObject(exampleClass) @Environment instead of @EnvironmentObject @Environment(Example.self) private var example This new setup is not letting me access $example.myArray. Is this intended? Could someone explain why?

At the moment, using Bindable for an object stored in Environment works in a cumbersome way: struct ContentView: View { @Environment(Model.self) var model var body: some View { @Bindable var model = model VStack { Text(model.someField.uppercased()) TextField("", text: $model.someField) someSubView } .padding() } @ViewBuilder var someSubView: some View { @Bindable var model = model TextField("", text: $model.someField) } } A new @Bindable needs to be instantiated for each computed property in the view, which creates boilerplate I would like to avoid. I made a new property wrapper which functions the same as the EnvironmentObject wrapper, but for Observable: @propertyWrapper struct EnvironmentObservable<Value: AnyObject & Observable>: DynamicProperty { @Environment var wrappedValue: Value public init(_ objectType: Value.Type) { _wrappedValue = .init(objectType) } public init() { _wrappedValue = .init(Value.self) } private var store: Bindable<Value>! var projectedValue: Bindable<Value> { store } mutating func update() { store = Bindable(wrappedValue) } } Example: struct ContentView: View { @EnvironmentObservable var model: Model var body: some View { VStack { Text(model.someField.uppercased()) SubView(value: $model.someField) someSubView } .padding() } var someSubView: some View { TextField("", text: $model.someField) } } I was wondering if there would be any downsides to using this method? In my testings it seems to behave the same, but I'm not sure if using this could have a performance impact.

Our app has an architecture based on ViewModels. Currently, we are working on migrating from the ObservableObject protocol to the Observable macro (iOS 17+). The official docs about this are available here: https://developer.apple.com/documentation/swiftui/migrating-from-the-observable-object-protocol-to-the-observable-macro Our ViewModels that were previously annotated with @StateObject now use just @State, as recommended in the official docs. Some of our screens (a screen is a SwiftUI view with a corresponding ViewModel) are presented modally. We expect that after dismissing a SwiftUI view that was presented modally, its corresponding ViewModel, which is owned by this view (via the @State modifier), will be deinitialized. However, it seems there is a memory leak, as the ViewModel is not deinitialized after a modal view is dismissed. Here's a simple code where ModalView is presented modally (through the .sheet modifier), and ModalViewModel, which is a @State of ModalView, is never deinitialized. import SwiftUI import Observation @Observable final class ModalViewModel { init() { print("Simple ViewModel Inited") } deinit { print("Simple ViewModel Deinited") // never called } } struct ModalView: View { @State var viewModel: ModalViewModel = ModalViewModel() let closeButtonClosure: () -> Void var body: some View { ZStack { Color.yellow .ignoresSafeArea() Button("Close") { closeButtonClosure() } } } } struct ContentView: View { @State var presentSheet: Bool = false var body: some View { Button("Present sheet modally") { self.presentSheet = true } .sheet(isPresented: $presentSheet) { ModalView { self.presentSheet = false } } } } #Preview { ContentView() } Is this a bug in the iOS 17 beta version or intended behavior? Is it possible to build a relationship between the View and ViewModel in a way where the ViewModel will be deinitialized after the View is dismissed? Thank you in advance for the help.