Touch is not being detected in Swift - ios

Question

I have been developing a simple game in Swift in order to increase my exposure towards the language syntax and concepts. I am currently facing a problem in which the touches are not detected in the game application. The application uses action for a key method to start the game but unfortunately, when I tap on the screen the SKSpriteNodes are not spawning from the top of the screen (at-least visually). I have entered a few print states to see if the code has reached certain methods but it looks like the cause of the problem is within the touch method as the print line is not executed at the touch method. Can someone help me identify what is my mistake and how to prevent this?
For reference purposes I have included the class:
import SpriteKit
import GameplayKit
class GameScene: SKScene {
private var counter: Int = 0
private var level: Int = 0
private var debug: SKLabelNode?
// Here we set initial values of counter and level. Debug label is created here as well.
override func didMove(to view: SKView) {
counter = 0
level = 1
backgroundColor = SKColor.gray
debug = SKLabelNode(fontNamed: "ArialMT")
debug?.fontColor = SKColor.purple
debug?.fontSize = 30.0
debug?.position = CGPoint(x: frame.midX, y: frame.midY)
debug?.text = "Counter : [ \(counter) ], Level [ \(level) ]"
if let aDebug = debug {
addChild(aDebug)
}
print(action(forKey: "counting") == nil)
}
//Method to start a timer. SKAction is used here to track a time passed and to maintain the current level
func startTimer() {
print("TIMER STARTED...")
weak var weakSelf: GameScene? = self
//make a weak reference to scene to avoid retain cycle
let block = SKAction.run({
weakSelf?.counter = (weakSelf?.counter ?? 0) + 1
//Maintaining level
if (weakSelf?.counter ?? 0) < 5 {
//level 1
weakSelf?.level = 1
} else if (weakSelf?.counter ?? 0) >= 5 && (weakSelf?.counter ?? 0) < 10 {
//level 2
weakSelf?.level = 2
} else {
//level 3
weakSelf?.level = 3
}
weakSelf?.debug?.text = "Counter : [ \(Int(weakSelf?.counter ?? 0)) ], Level [ \(Int(weakSelf?.level ?? 0)) ]"
})
run(SKAction.repeatForever(SKAction.sequence([SKAction.wait(forDuration: 1), block])), withKey: "counting")
}
//Method for stopping the timer and reset everything to the default state.
func stopTimer() {
print("TIMER STOPPED.")
if action(forKey: "counting") != nil {
removeAction(forKey: "counting")
}
counter = Int(0.0)
level = 1
debug?.text = "Counter : [ \(counter) ], Level [ \(level) ]"
}
//Get current speed based on time passed (based on counter variable)
func getCurrentSpeed() -> CGFloat {
if counter < 5 {
//level 1
return 1.0
} else if counter >= 5 && counter < 10 {
//level 2
return 2.0
} else {
//level 3
return 3.0
}
}
//Method which stops generating stones, called in touchesBegan
func stopGeneratingStones() {
print("STOPPED GENERATING STONES...")
if action(forKey: "spawning") != nil {
removeAction(forKey: "spawning")
}
}
func randomFloatBetween(_ smallNumber: CGFloat, and bigNumber: CGFloat) -> CGFloat {
let diff: CGFloat = bigNumber - smallNumber
//return (CGFloat(arc4random_uniform(UInt32(CGFloat(RAND_MAX) + 1 / CGFloat(RAND_MAX) * diff )))) + smallNumber
return CGFloat(arc4random() % (UInt32(RAND_MAX) + 1)) / CGFloat(RAND_MAX) * diff + smallNumber
}
//Method for generating stones, you run this method when you want to start spawning nodes (eg. didMoveToView or when some button is clicked)
func generateStones() {
print("GENERATING STONES...")
let delay = SKAction.wait(forDuration: 2, withRange: 0.5)
//randomizing delay time
weak var weakSelf: GameScene? = self
//make a weak reference to scene to avoid retain cycle
let block = SKAction.run({
let stone: SKSpriteNode? = weakSelf?.spawnStone(withSpeed: weakSelf?.getCurrentSpeed() ?? 0.0)
stone?.zPosition = 20
if let aStone = stone {
weakSelf?.addChild(aStone)
}
})
run(SKAction.repeatForever(SKAction.sequence([delay, block])), withKey: "spawning")
}
//Returns stone with moving action added. Inside, you set standard things, like size, texture, physics body, name and position of a stone
func spawnStone(withSpeed stoneSpeed: CGFloat) -> SKSpriteNode? {
print("SPAWNNING STONES...")
let stoneSize = CGSize(width: 30, height: 30) //size of shape.
//you can randomize size here
let stonePosition = CGPoint(x: randomFloatBetween(0.0, and: frame.size.width), y: frame.maxY) //initial position
//you can randomize position here
let stone = SKSpriteNode(color: SKColor.green, size: stoneSize) //setting size and color.
stone.name = "stone" //named shape so we can check collision.
//this helps if you want to enumerate all stones by name later on in your game
stone.position = stonePosition //set position.
let move = SKAction.moveBy(x: 0, y: -200, duration: 3.25)
//one way to change speed
move.speed = stoneSpeed
let moveAndRemove = SKAction.sequence([move, SKAction.removeFromParent()])
stone.run(moveAndRemove, withKey: "moving")
//access this key if you want to stop movement
return stone
}
func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
/* Called when a touch begins */
//just a simple way to start and stop a game
/**
TOUCH METHOD NOT WORKING.
*/
if action(forKey: "counting") == nil {
print("HERE")
startTimer()
generateStones()
} else {
print("OR HERE")
stopTimer()
stopGeneratingStones()
}
}
}

Answer 1

I have fixed the problem to my own question after some debugging. I have realised that the touchesBegan method does not use override the super, hence the application is mistaking it for a local method. To overcome this problem simply adding the override will fix problem.
change this:
func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
/* Called when a touch begins */
//just a simple way to start and stop a game
/**
TOUCH METHOD NOT WORKING.
*/
if action(forKey: "counting") == nil {
print("HERE")
startTimer()
generateStones()
} else {
print("OR HERE")
stopTimer()
stopGeneratingStones()
}
}
to this:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
/* Called when a touch begins */
//just a simple way to start and stop a game
/**
TOUCH METHOD NOT WORKING.
*/
if action(forKey: "counting") == nil {
print("HERE")
startTimer()
generateStones()
} else {
print("OR HERE")
stopTimer()
stopGeneratingStones()
}
}