SpriteView-not-updating

Sample SwiftUI / SpriteKit Xcode 13 project showing a simple ContentView that displays a SpriteView using a SceneStore manager with an @EnvironmentObject var sceneStore: SceneStore property.

The ContentView has a "Restart" button that should recreate the SKScene when pressed. The SKScene gets recreated inside the SceneStore and the ContentView's Text view (with the new time assigned to the name property of the scene), but the SpriteView doesn't change the scene.

It seems that the SpriteView keeps the initial scene in memory, and doesn't let it go to replace it with the new scene. This can be seen in the Console, by hitting the Restart button twice and looking for something like "-- Scene 7:49:44 PM deinit --":

on first press, a second scene is created but the first scene doesn't get deinitialized because it is held by the SpriteView
on second press, a third scene is created, the second scene gets deinitialized from the SceneStore, but the first scene is still inside the SpriteView

The updates from the @Published var updates = 0 property inside the scene also stop (at the top of the screen), because the new scene that gets created is not added into the view, so the SKScene.didMove(to view:) method is never called, thus the updates property is 0.

The "Paused:" button shows a similar problem with the SpriteView not updating when the state changes.

Related questions:

All the code is in ContentView.swift:

import SwiftUI
import SpriteKit

class GameScene: SKScene, ObservableObject {
    @Published var updates = 0
    private let label = SKLabelNode(text: "Updates in SKScene:\n0")
    
    override func didMove(to view: SKView) {
        addChild(label)
        label.numberOfLines = 4
        label.position = CGPoint(x: 0, y: -100)
    }
    
    override func update(_ currentTime: TimeInterval) {
        updates += 1
        label.text = "Updates in SKScene:\n\(updates)\nScene created at:\n\(name!)"
    }
    
    deinit {
        print("-- Scene \(name!) deinit --")
    }
}

class SceneStore : ObservableObject {
    @Published var currentScene: GameScene
    
    init() {
        currentScene = SceneStore.createScene()
    }
    
    func restartLevel() {
        currentScene = SceneStore.createScene()
    }
    
    // MARK: - Class Functions
    
    static private func createScene() -> GameScene {
        let scene = GameScene()
        scene.size = CGSize(width: 300, height: 400)
        scene.anchorPoint = CGPoint(x: 0.5, y: 0.5)
        scene.scaleMode = .fill
        scene.name = Date().formatted(date: .omitted, time: .standard)
        return scene
    }
}

struct ContentView: View {
    @EnvironmentObject private var sceneStore: SceneStore
    @EnvironmentObject private var scene: GameScene
    @State private var paused = false
    
    var body: some View {
        if #available(iOS 15.0, *) {
            print(Self._printChanges())
        }
        return ZStack {
            SpriteView(scene: scene, isPaused: paused).ignoresSafeArea()
            VStack {
                Text("Updates from SKScene: \(scene.updates)").padding().foregroundColor(.white)
                Text("Scene created at: \(scene.name!)" as String).foregroundColor(.white)
                Button("Restart") {
                    sceneStore.restartLevel()
                }.padding()
                Button("Paused: \(paused)" as String) {
                    paused.toggle()
                }
                Spacer()
            }
        }
    }
}

clns/SpriteView-not-updating

SpriteView-not-updating