I get an error "EXC_BAD_ACCESS" when I try to call...

# multiplatform

[Stefan Oltmann]

I get an error "EXC_BAD_ACCESS" when I try to call "onReceive":

struct ContentView: View {
  @EnvironmentObject var store: ObservablePhotoStore
  var body: some View {
    VStack {
      Button("Show details") {
        store.dispatch(PhotoAction.Refresh())
      }
    }
    onReceive(store.$state) { value in
      print("test")
    }
  }
}

This is the observerved object:

class ObservablePhotoStore: ObservableObject {
   
  @Published public var state: PhotoState = PhotoState(progress: false, photos: [], selectedPhoto: nil, testString: "never updated")
  @Published public var sideEffect: PhotoSideEffect?
   
  let store: PhotoStore
   
  var stateWatcher : Closeable?
  var sideEffectWatcher : Closeable?

  init(store: PhotoStore) {
     
    self.store = store
     
    stateWatcher = self.store.watchState().watch { [weak self] state in
      self?.state = state
    }
     
    sideEffectWatcher = self.store.watchSideEffect().watch { [weak self] state in
      self?.sideEffect = state
    }
  }
   
  public func dispatch(_ action: PhotoAction) {
    store.dispatch(action: action)
  }
   
  deinit {
    stateWatcher?.close()
    sideEffectWatcher?.close()
  }
}

@main
class MyPhotoApp: App {
   
  let photoRepository: PhotoRepositoryImpl
  let store: ObservablePhotoStore
   
  required init() {
    photoRepository = PhotoRepositoryImpl()
    store = ObservablePhotoStore(store: PhotoStore(photoRepository: photoRepository))
  }
   
  var body: some Scene {
    WindowGroup {
      ContentView().environmentObject(store)
    }
  }
}

I'm new to SwitUI and I try to learn from https://github.com/Kotlin/kmm-production-sample how to receive changes in StateFlow to update my Swift UI.

I'm looking for a simple way to do that and that sample project is already very complex.

[Stefan Oltmann]

Eventually my goal is to throw my "store.state.photos" Array into a SwiftUI List that should be re-rendered if the contents change.

[Stephen Gazzard]

What is PhotoState ?

[Stefan Oltmann]

data class PhotoState(
    val progress: Boolean,
    val photos: List<Photo>,
    val selectedPhoto: Photo? = null,
    val testString: String
) : State

interface State
interface Action
interface Effect

interface Store<STATE : State, ACTION : Action, EFFECT : Effect> {

    fun observeState(): StateFlow<STATE>

    fun observeSideEffect(): Flow<EFFECT>

    fun dispatch(action: ACTION)

}

[Stefan Oltmann]

In the original code from @Kathrin Petrova this seems to work somehow, but not for me. I'm puzzled.