not able to apply impulse to SKPhysicsbody

Question

so im working on a kind of side scroller, first game with Xcode and swift but here is what i have:

    import SpriteKit
import GameplayKit

let jumpButton = SKSpriteNode(imageNamed: "jumpButton")
var jumpButtonPosition = CGPoint(x: 500, y: -250)
var selectedButton = "nodeName"

let background1 = SKSpriteNode(imageNamed: "Woods_Background")
let background2 = SKSpriteNode(imageNamed: "Woods_Background")
let background3 = SKSpriteNode(imageNamed: "Woods_Background")

let player = SKSpriteNode(imageNamed: "player")
var playerColor = UIColor.red
var playerSize = CGSize(width: 50, height: 100)
var playerPhysicsBody = player.physicsBody
let playerJumpVector = CGVector(dx: 0, dy: 50)

let ground = SKSpriteNode()

var camPosition = CGPoint()
var playerPosition = camPosition
let cam = SKCameraNode()

var anchorpoint = CGPoint(x: 0.5, y: 0.5)
let endPoint = CGPoint(x: 100000, y: 0)

class GameScene: SKScene {

    override func didMove(to view: SKView) {

        super.didMove(to: view)
        self.camera = cam
        self.addChild(cam)

        spawnPlayer()
        spawnBackground()
        spawnJumpButton()
    }

    func spawnGround(){
        scene?.addChild(ground)
        ground.size = CGSize(width: size.width * 1, height: size.height * 0.1)
        ground.position = CGPoint(x: size.width * 0.5, y: size.height * 0.05)
        ground.physicsBody = SKPhysicsBody(rectangleOf: CGSize(width: size.height, height: size.height * 0.1))
        ground.physicsBody?.isDynamic = false
    }

    func spawnPlayer() {
        scene?.addChild(player)
        player.position = camPosition
        player.zPosition = 1
        player.size = playerSize
        player.physicsBody = playerPhysicsBody
        playerPhysicsBody?.affectedByGravity = false
        playerPhysicsBody?.mass = 50
    }

    func spawnJumpButton() {
        scene?.addChild(jumpButton)
        jumpButton.position = jumpButtonPosition
        jumpButton.zPosition = 0.5
        jumpButton.size = CGSize(width: 100, height: 100)
        jumpButton.name = "jumpButton"
        jumpButton.isUserInteractionEnabled = false
    }

    func jumpPlayer() {
        playerPhysicsBody?.applyImpulse(playerJumpVector)
    }

    func spawnBackground() {
        scene?.addChild(background1)
        background1.anchorPoint = CGPoint(x: 0.5, y: 0.5)
        background1.position.x = 0
        background1.zPosition = 0
        background1.size = CGSize(width: 3240, height: 1080)

        scene?.addChild(background2)
        background2.anchorPoint = CGPoint(x: 0.5, y: 0.5)
        background2.position.x = 3240
        background2.zPosition = 0
        background2.size = CGSize(width: 3240, height: 1080)

        scene?.addChild(background3)
        background3.anchorPoint = CGPoint(x: 0.5, y: 0.5)
        background3.position.x = 6480
        background3.zPosition = 0
        background3.size = CGSize(width: 3240, height: 1080)
    }

    override func update(_ currentTime: TimeInterval) {

        if cam.position.x > background2.position.x {
            background1.position.x = background3.position.x + 3240
        }
        if cam.position.x > background3.position.x {
            background2.position.x = background1.position.x + 3240
        }
        if cam.position.x > background1.position.x {
            background3.position.x = background2.position.x + 3240
        }
        camPosition.x = playerPosition.x
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
            if let touch = touches.first {
                if selectedButton == "nodeName" {
                    if jumpButton.contains(touch.location(in: self)) {
                       jumpPlayer()
                    }
                }
            }
    }

    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
        selectedButton = "nodeName"
    }
}

Im trying to get the player to jump with use of the button, when clicked the player should jump about 20 pixels in the air. same applies for the running motion of the player, cant get it to run forever without animations, with which you cant do other stuff at the same time.

Answer 1

The player.physicalBody is nil and need to handle!

   func spawnPlayer() {
    scene?.addChild(player)
    player.position = camPosition
    player.zPosition = 1
    player.size = playerSize

    //Here adding two lines
    player.physicsBody =  SKPhysicsBody()
    playerPhysicsBody?.linearDamping = 1

     playerPhysicsBody?.affectedByGravity = false
    playerPhysicsBody?.mass = 50
     }


     func jumpPlayer() {
    //Here changing one line
    playerPhysicsBody?.applyImpulse(playerJumpVector)
     }