Adding SKScene to UIViewController gives me errors - swift

Question

What I want
An infinite background that randomly adds objects (in my cases little stars) to the middle of the screen. Then those objects needs to move out of the screen with a certain speed. This way I want to give the user the feeling they are moving "into space", seeing stars they are passing.
What I have
A single view application with a UIViewController class.
Problem
I think the right way is to add a SKScene which will do the task I want. However, adding the SKScene class next to UIViewController gives me an error: "multiple inheritance from classes 'UIViewController' and 'SKScene'". I need to add the SKScene to an existence UIViewController, in order to call some important functions. When searching for this on Stackoverflow I came across this: SKScene in UIViewController But I can not call certain functions like "override func update(current time: CFTimeInterval){}", because the answer doesn't show how to implement the SKScene class. This answer deletes the whole UIViewController class: Adding an SKScene to a UIViewController?. The other answers are not helping me.
Question
What is the correct way of adding a SKScene class to an existence UIViewController class, so I can accomplish what I want?
Edit: Came across this on 9gag and its exactly what I want: http://9gag.com/gag/aWmZAPZ Those stars are coming from left top, the respawning should be in the middle of the screen at my app.

Answer 1

Certainly, it's possible. Instead of directly add SKScene to UIViewController, you need to warp SKScene by SKView first, and then add SKView to UIViewController
import UIKit
import SpriteKit
class GameViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Configure the view.
// Core:- convert the base view/UIView of UIViewController to SKView
let rootView = self.view as! SKView
// skView.showsFPS = true
// skView.showsNodeCount = true
/* Sprite Kit applies additional optimizations to improve rendering performance */
rootView.ignoresSiblingOrder = true
rootView.frameInterval = 1
//init your SKScene
let rootMenuScene = YourScene(size: rootView.bounds.size)
rootMenuScene.scaleMode = .resizeFill
//warp in SKView
rootView.presentScene(rootMenuScene)
}
...
}