Spritekit and swiftui, change scene a better way - swift

Question

I wrote this simple few line of code to swap between 2 scene in Swiftui using SpriteKit, I'm try to understand if there could be a (better) different way to change from one scene to another using a button.
struct ContentView: View {
#StateObject var firstscene = FirstScene()
#StateObject var secondscene = SecondScene()
#State var changeScene = false
var body: some View {
ZStack{
if changeScene {
SpriteView(scene: firstscene)
} else {
SpriteView(scene: secondscene)
}
Button {
changeScene.toggle()
} label: {
Text("Change")
}
}
}
}
// the 2 SKScene created using a sub class of SKscene
class FirstScene: SKScene, ObservableObject {
let firstScene = SKScene(fileNamed: "FirstScene")
override func didMove(to view: SKView) {
scene?.view?.presentScene(firstScene)
}
}
class SecondScene: SKScene, ObservableObject {
let secondScene = SKScene(fileNamed: "SecondScene")
override func didMove(to view: SKView) {
scene?.view?.presentScene(secondScene)
}
}
now my doubt is, I'm change the SpriteView in the contentView using a var changeScene, could be done the same things in some other way using another approach?
open to any suggestions, I'm try to understand this framework .
thanks

Answer 1

You are using a standard way of switching views. You could clean your code up a bit like this:
struct ContentView: View {
#State var changeScene = false
var body: some View {
ZStack{
SpriteView(scene: (changeScene ? FirstScene() : SecondScene())) // this is a terniary operator
Button {
changeScene.toggle()
} label: {
Text("Change")
}
}
}
}
The new views do not need to be #StateObjects. You can call the View Types directly in your view.
Note: I am away from my computer so this is not tested.

Answer 2

iOS 14, Swift 5
This is tested and comes from this article.
https://betterprogramming.pub/build-a-game-of-chess-with-spritekit-3229c23bdba0
import SwiftUI
import SpriteKit
struct ContentView: View {
#State var switcher = false
var scene: SKScene {
let scene = GameScene.shared
scene.size = CGSize(width: 256, height: 512)
scene.scaleMode = .fill
scene.backgroundColor = .red
scene.name = "red"
return scene
}
var scene2: SKScene {
let scene2 = GameScene2.shared
scene2.size = CGSize(width: 256, height: 512)
scene2.scaleMode = .fill
scene2.backgroundColor = .blue
scene2.name = "blue"
return scene2
}
var body: some View {
if switcher {
SpriteView(scene: scene)
.frame(width: 256, height: 512)
.ignoresSafeArea()
.background(Color.red)
.onAppear {
scene2.isPaused = true
}
.onDisappear {
scene2.isPaused = false
}
} else {
SpriteView(scene: scene2)
.frame(width: 256, height: 512)
.ignoresSafeArea()
.background(Color.blue)
.onAppear {
scene.isPaused = true
}
.onDisappear {
scene.isPaused = false
}
}
Button {
withAnimation(.easeInOut(duration: 1.0)) {
switcher.toggle()
}
} label: {
Text("play")
}
}
}