ObservableObj

import SwiftUI
import SpriteKit


class GameScene: SKScene, SKPhysicsContactDelegate, ObservableObject {  // <<: Here 1
  //  @Published var updates = 0
    @Published var gameScore = 0 // <<: Here 2
    @Published var lenght: CGFloat = 1
          var up: Bool = false

  //  let removeLabel = SKAction.sequence([SKAction.fadeIn(withDuration: 0.3), SKAction.wait(forDuration: 0.8), SKAction.fadeOut(withDuration: 0.3)])
    let tball = SKShapeNode(circleOfRadius: 20)
    
    var lastUpdateTime2 : TimeInterval = 0  
    override func didMove(to view: SKView) {
        backgroundColor = .yellow
        physicsBody = SKPhysicsBody(edgeLoopFrom: frame)        
        tball.position = CGPoint(x: 0, y: 0)
             tball.fillColor = .blue
             self.addChild(tball)
     //   tball.zPosition = 10
    }    
    func change(){
       if self.lenght > 100 {
              up = false
         }else if (self.lenght < 10){
               up = true
       }
            up ? (self.lenght += 1) : (self.lenght -= 1)
       }
override func update(_ currentTime: TimeInterval) {
      //   self.change()
  if lastUpdateTime2 == 0 {
        lastUpdateTime2 = currentTime
     }
    if currentTime - lastUpdateTime2 > 1 - 0.9 {
       self.change()
       lastUpdateTime2 = currentTime
        }
           }
    /*
    func ball() {
   let ball = SKShapeNode(circleOfRadius: 20)
    let MinValue = self.size.width / 8
   let MaxValue = self.size.width  - 50
    let SpawnPoint = UInt32(MaxValue - MinValue)
   ball.position = CGPoint(x: CGFloat(arc4random_uniform(SpawnPoint)), y: 200)
      ball.fillColor = .blue
      self.addChild(ball)
    }
     */
 func ball() {
      let moveDown = SKAction.moveTo(x:130, duration: 2.5)
      let moveUp = SKAction.moveTo(x: -130, duration: 2.5)
      let actionSequence2 = SKAction.sequence([moveDown, moveUp])
      let moveRepeat = SKAction.repeatForever(actionSequence2)
    tball.run(moveRepeat, withKey: "moveX")
    }
 func ball2() {
    let moveDown2 = SKAction.moveTo(x:130, duration: -2.5)
    let moveUp2 = SKAction.moveTo(x: -130, duration: -2.5)
    let actionSequence3 = SKAction.sequence([moveDown2, moveUp2])
    let moveRepeat2 = SKAction.repeatForever(actionSequence3)
    tball.run(moveRepeat2, withKey: "moveX2")
    }
    func addScore(){
        if gameScore < 10 {
            gameScore += 1            
        } else {
            gameScore += 5            
        }
    }    
}
struct ContentView: View {
    @State var flag = true
    @State var showingSheet : Bool = false
 //   @StateObject var gameScene = GameScene() // <<: Here 3
 /*
    let scene: GameScene = {
     let scene = GameScene()
     scene.size = CGSize(width: 300, height: 300)
     scene.scaleMode = .fill
     return scene
 }()
*/
@StateObject private var scene: GameScene = {
    let scene = GameScene()
     scene.size = CGSize(width: 300, height: 300)
     scene.anchorPoint = CGPoint(x: 0.5, y: 0.5)
      scene.scaleMode = .fill
       return scene
  }()           
    var body: some View {
        Spacer()
        VStack {
        Button(action: {
            if(self.flag){
             scene.ball()
             self.flag = false
          }
           else{
              scene.ball2()
             self.flag = true
           }
           }
        ){
          Text("ball start on off")
             .font(.title3)
              .foregroundColor(Color.purple)
               .padding(.bottom, 20)
  }
       Button(
           action: { showingSheet = true },
            label: {
           Text("ShowSheet")
          })
        .sheet(isPresented: $showingSheet){
         SecondSheet()
          }
 }
     ZStack {
         SpriteView(scene: scene)
             .frame(width: 300, height: 300)
             .ignoresSafeArea()
        Circle().frame(width: scene.lenght, height: scene.lenght)
            .foregroundColor(.green)
              .padding(.top, 150)
   
        Button(action: {
          scene.addScore()
            }) {
             Text("Score: \(scene.gameScore)")
              .font(.title3)
               .frame(width: 110, height: 30, alignment: .center)
                .foregroundColor(Color.white)
                .background(Color.pink)
                 .cornerRadius(5, antialiased: true)
                 .padding(.bottom, 130)
      }
     }
     .padding(.bottom, 110)       
    }    
}
struct SecondSheet: View {
    @Environment(\.dismiss) var dismiss
     var body: some View {
         VStack{
   Text("SecondSheet")
       .fontWeight(.heavy)
       .font(.title)
   Button("画面を閉じる") {
     dismiss()
     }
     }
 }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}