CODEWITHSUNDEEP
swiftswift2
Brendan Wu
Brendan Wu

Reputation: 1

Swift : use of unresolved identifier

I'm trying to make a flappy bird clone and I am getting this message... "use of unresolved identifier for 'Ghost'." The error is occuring in the touches began function. I'm knew to all this so I don't really know what's going. I was following a tutorial coded in swift 2.1 so I'm not sure if that may be a problem, but I'm almost sure I copied it line for line. 

import SpriteKit


struct PhysicsCategory {
    static var Ghost : UInt32 = 0x1 << 1
    static var Ground : UInt32 = 0x1 << 2
    static var Wall : UInt32 = 0x1 << 3
}


class GameScene: SKScene {
    override func didMoveToView(view: SKView) {
        /* Setup your scene here */

    var Ground = SKSpriteNode()
    var Ghost = SKSpriteNode()


    Ground = SKSpriteNode(imageNamed: "Ground")
    Ground.setScale(0.5)
    Ground.position = CGPoint(x: self.frame.width/2, y:0 + Ground.frame.height/2)

    Ground.physicsBody = SKPhysicsBody(rectangleOfSize: Ground.size)
    Ground.physicsBody?.categoryBitMask = PhysicsCategory.Ground
    Ground.physicsBody?.collisionBitMask = PhysicsCategory.Ghost
    Ground.physicsBody?.contactTestBitMask = PhysicsCategory.Ghost
    Ground.physicsBody?.affectedByGravity = false
    Ground.physicsBody?.dynamic = false


    self.addChild(Ground)



    Ghost = SKSpriteNode(imageNamed: "Ghost")
    Ghost.size = CGSize(width:60, height: 70)
    Ghost.position = CGPoint(x: self.frame.width/2 - Ghost.frame.width, y: self.frame.height/2)
    Ghost.physicsBody = SKPhysicsBody(circleOfRadius: Ghost.frame.height/2)
    Ghost.physicsBody?.categoryBitMask = PhysicsCategory.Ghost
    Ghost.physicsBody?.collisionBitMask = PhysicsCategory.Ground | PhysicsCategory.Wall
    Ghost.physicsBody?.contactTestBitMask = PhysicsCategory.Ground | PhysicsCategory.Wall
    Ghost.physicsBody?.affectedByGravity = true
    Ghost.physicsBody?.dynamic = true




    self.addChild(Ghost)


    createWalls()
}

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
   /* Called when a touch begins */

    Ghost.physicsBody?.velocity = CGVectorMake(0,0)
    Ghost.physicsBody?.applyImpulse(CGVectorMake(0, 60))



}


func createWalls() {

    let wallPair = SKNode()

    let topWall = SKSpriteNode(imageNamed: "Wall")
    let bottomWall = SKSpriteNode(imageNamed: "Wall")

    topWall.position = CGPoint(x: self.frame.width/2, y:self.frame.height/2 + 350)
    bottomWall.position = CGPoint(x: self.frame.width/2, y:self.frame.height/2 - 350)

    topWall.setScale(0.5)
    bottomWall.setScale(0.5)

    topWall.zRotation = CGFloat(M_PI)

    wallPair.addChild(topWall)
    wallPair.addChild(bottomWall)

    self.addChild(wallPair)


}


override func update(currentTime: CFTimeInterval) {
    /* Called before each frame is rendered */
}
}

Upvotes: 0

Views: 697

Answers (1)

NRitH
NRitH

Reputation: 13893

Your Ghost is not a data type; it's the name of a single variable that you create in your didMoveToView() method. You need to make it a property of your class so that it can still be initialized in didMoveToView(), but used in other methods, like touchesBegan(). Just move your var Ghost declaration outside of the method, and keep the Ghost = SKSpriteNode(...) where it is.

It should also be mentioned that it's a really bad idea to have a local variable or a property have the same name as one of your enum cases; anybody who reads the code could get understandably confused, even though they're perfectly legal as far as the compiler is concerned. It's also not very Swift-like to capitalize your variable or property names.

And lastly, I have to implore you not to create another Flappy Bird clone! We have enough of those to last a lifetime.

Upvotes: 2

Related Questions