scene in SpriteKit - ios

Question

hello thereI'm working in my Game but I face a problem when I'm trying to change the scene. I sit up a button and it's work but when the transfer happened I can't see my Background this is my code
This is the code for my Game scene. the back ground ok
import SpriteKit
class GameScene: SKScene {
// Next scene button
var nextButton: UIButton!
let background = SKSpriteNode(imageNamed: "BG")
override func didMoveToView(view: SKView) {
backgroundColor = SKColor.whiteColor()
// Background Image
background.position = CGPoint(x: size.width / 2, y: size.height / 2)
background.size = CGSize(width: 2100, height: 1200)
background.zPosition = -3
addChild(background)
// Next button Action
nextButton = UIButton(frame: CGRect(x: 0, y: 0, width: frame.size.width / 2, height:300))
nextButton.center = CGPoint(x: view.frame.size.width / 7.3, y: view.frame.size.width / 3)
nextButton.setTitle("Next Button", forState: UIControlState.Normal)
nextButton.setTitleColor(UIColor.redColor(), forState: UIControlState.Normal)
nextButton.addTarget(self, action: Selector("Next"), forControlEvents: UIControlEvents.TouchUpInside)
self.view?.addSubview(nextButton)
}
func Next() {
self.view?.presentScene(Play(), transition: SKTransition.crossFadeWithDuration(1.0))
nextButton.removeFromSuperview()
background.removeFromParent()
}
}
this is the code for my Play scene. the back ground is not appearing i don't know why
import Foundation
import SpriteKit
class Play: SKScene {
override func didMoveToView(view: SKView) {
backgroundColor = SKColor.whiteColor()
// Background Image
let background = SKSpriteNode(imageNamed: "BG")
background.position = CGPoint(x: size.width / 2, y: size.height / 2)
//background.size = CGSize(width: 2100, height: 1200)
background.zPosition = -3
addChild(background)
}
}

Answer 1

Are you checking that the play scene is actually being transitioned too?.
You should also init the new scene with a size if you dont use .sks files.
func Next() {
nextButton.removeFromSuperview()
let scene = Play(size: self.size) // get size of current scene
self.view?.presentScene(scene, transition: SKTransition.crossFadeWithDuration(1.0))
}
If you do use .sks files (xCode visual editor) than you would need to create a new .sks file called Play and load the scene like so
func Next() {
if let scene = Play(fileNamed: "Play") {
nextButton.removeFromSuperview()
self.view?.presentScene(scene, transition: SKTransition.crossFadeWithDuration(1.0))
}
}
As a tip you dont have to remove SKSpriteNodes after changing scenes. You are already adding them to the scene (addChild) and they will get removed for you automatically.
You still have to remove UIKit stuff tho, such as your UIButton, because they get added to your view and not the SKScene.