【Swift】Apple 公式サンプル にみる @Modelactor を singleton にして ViewModifier にすると便利 👉 https://android.benigumo.com/20240711/modelactor-singleton/

LocalData.swift

import SwiftUI
import SwiftData

@ModelActor
actor LocalData {
  nonisolated(unsafe) private(set) static var shared: LocalData! // *

  private var task: Task<Void, Never>?

  static func createInstance(modelContainer: ModelContainer) { // *
    shared = LocalData(modelContainer: modelContainer)
  }

  func load() async {
  }

  func update() {
    task = Task {
    }
  }

  func cancel() {
    task?.cancel()
  }

  func status() -> Status { // ?
  }
  
  nonisolated func fetch() sync -> [Item] { // *
    (try? modelContext.fetch(FetchDescriptor<Item>())) ?? []
  }
}