Sprite Kit Creating Separate Class - swift

Question

Attempting to design a game using Sprite-Kit I found that it would be easier to create a seperate class for one of my game objects being a laser from a ship. Within that class I would have some functions maybe such as updating, shooting etc. But whenever I create another class none of the variables I make are "declared". This is my code
import UIKit
import SpriteKit
class laser: SKSpriteNode {
let laser : SKSpriteNode = SKSpriteNode(imageNamed:"playerShip")
laser.position = CGPoint(x: 100, y: 200)//This is where it says no declaration
}

Answer 1

This is because you need to initiate the class.
In your example you would need to do the following which would allow you instantiate a laser like this laser()
class laser: SKSpriteNode {
let laser: SKSpriteNode = SKSpriteNode(imageNamed: "playerShip")
init() {
super.init(texture: nil, color: .clear, size: laser.size)
laser.position = CGPoint(x: 100, y: 200)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
But you probably really wanted this, which allows you to instantiate a laser like this let aLaser = laser("playerShip"). Then you can change the position like this alaser.position = CGPoint(x: 100, y: 200).
This method allows you to change the sprite and position easily for different lasers. Unless your game only has one laser.
class laser: SKSpriteNode {
init(_ imageName: String) {
let texture: SKTexture = SKTexture(imageNamed: imageName)
super.init(texture: texture, color: .clear, size: texture.size())
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}