Ios 我如何用按钮开始这个游戏？我使用的是Xcode 6、Swift和SpriteKit

我如何用按钮开始这个游戏？我使用的是Xcode 6、Swift和SpriteKit。我的游戏在iOS模拟器上运行时启动，但我想通过按下播放按钮来启动它

这是我的代码：

import SpriteKit

import AVFoundation

class GameScene: SKScene, SKPhysicsContactDelegate{

    var cat:SKSpriteNode!
    var skyColor:SKColor!
    var obstTextureUp:SKTexture!
    var obstTextureDown:SKTexture!
    var moveObstAndRemove:SKAction!
    var moving:SKNode!
    var obsts:SKNode!
    var canRestart = Bool()
    var scoreLabelNode:SKLabelNode!
    var score = NSInteger()
    let verticalObstGap = 150.0
    var playButton:SKSpriteNode = SKSpriteNode(imageNamed:"playButton")

    let catCategory: UInt32 = 1 << 2
    let worldCategory: UInt32 = 1 << 1
    let obstCategory: UInt32 = 1 << 2
    let scoreCategory: UInt32 = 1 << 3

    override func didMoveToView(view: SKView) {
        canRestart = true
        self.physicsWorld.gravity = CGVectorMake( 0.0, -6.3 )
        self.physicsWorld.contactDelegate = self
        moving = SKNode()
        self.addChild(moving)
        obsts = SKNode()
        moving.addChild(obsts)
        let Label = SKSpriteNode(imageNamed: "Label")
        Label.position = CGPoint(x:515,y:650)
        Label.size = CGSizeMake(Label.frame.size.width, 60)
        self.addChild(Label)
        playButton.position = CGPoint(x: self.frame.size.width / 2 , y: self.frame.size.height / 2)
        playButton.setScale(0.5)
        self.addChild(playButton)
        let TextureG = SKTexture(imageNamed: "G")
        TextureG.filteringMode = .Nearest

        let TextureS = SKTexture(imageNamed: "S")
        TextureS.filteringMode = .Nearest

        obstTextureUp = SKTexture(imageNamed: "obstUp")
        obstTextureUp.filteringMode = .Nearest
        obstTextureDown = SKTexture(imageNamed: "obstDown")
        obstTextureDown.filteringMode = .Nearest
        let moveGSprite = SKAction.moveByX(-TextureG.size().width * 2.0, y: 0, duration: NSTimeInterval(0.02 * TextureG.size().width * 2.0))

        let resetGSprite = SKAction.moveByX(TextureG.size().width * 2.0, y: 0, duration: 0.0)

        let moveGSpritesForever = SKAction.repeatActionForever(SKAction.sequence([moveGSprite,resetGSprite]))

        for var i:CGFloat = 0; i < 2.0 + self.frame.size.width / ( TextureG.size().width * 2.0 ); ++i {
            let sprite = SKSpriteNode(texture: TextureG)
            sprite.setScale(2.0)
            sprite.position = CGPointMake(i * sprite.size.width, sprite.size.height / 2.0)
            sprite.runAction(moveGSpritesForever)
            moving.addChild(sprite)
        }


        let moveSSprite = SKAction.moveByX(-skyTexture.size().width * 2.0, y: 0, duration: NSTimeInterval(0.1 * skyTexture.size().width * 2.0))
        let resetSSprite = SKAction.moveByX(TextureS.size().width * 2.0, y: 0, duration: 0.0)
        let moveSSpritesForever = SKAction.repeatActionForever(SKAction.sequence([moveSSprite,resetSSprite]))

        for var i:CGFloat = 0; i < 2.0 + self.frame.size.width / ( skyTexture.size().width * 2.0 ); ++i {
            let sprite = SKSpriteNode(texture: TextureS)
            sprite.setScale(2.0)
            sprite.zPosition = -20
            sprite.position = CGPointMake(i * sprite.size.width, sprite.size.height / 2.0 + TextureG.size().height * 2.0)
            sprite.runAction(moveSSpritesForever)
            moving.addChild(sprite)
        }

        let distanceToMove = CGFloat(self.frame.size.width + 2.0 * obstTextureUp.size().width)
        let moveObsts = SKAction.moveByX(-distanceToMove, y:0.0, duration:NSTimeInterval(0.01 * distanceToMove))
        let removeObsts = SKAction.removeFromParent()
        moveObstsAndRemove = SKAction.sequence([moveObsts, removeObsts])

        let spawn = SKAction.runBlock({() in self.spawnObsts()})
        let delay = SKAction.waitForDuration(NSTimeInterval(2.0))
        let spawnThenDelay = SKAction.sequence([spawn, delay])
        let spawnThenDelayForever = SKAction.repeatActionForever(spawnThenDelay)
        self.runAction(spawnThenDelayForever)

        let catTexture1 = SKTexture(imageNamed: "cat-1")
        catTexture1.filteringMode = .Nearest
        let catTexture2 = SKTexture(imageNamed: "cat-2")
        catTexture2.filteringMode = .Nearest
        let catTexture3 = SKTexture(imageNamed: "cat-3")
        catTexture1.filteringMode = .Nearest
        let catTexture4 = SKTexture(imageNamed: "cat-4")
        catTexture2.filteringMode = .Nearest

        let anim = SKAction.animateWithTextures([catTexture1, catTexture2, catTexture3, catTexture4], timePerFrame: 0.11)
        let clip = SKAction.repeatActionForever(anim)

        cat = SKSpriteNode(texture: catTexture1)
        cat.setScale(2.0)
        cat.position = CGPoint(x: self.frame.size.width * 0.35, y:self.frame.size.height * 0.6)
        cat.runAction(clip)

        cat.physicsBody = SKPhysicsBody(circleOfRadius: bird.size.height / 2.0)
        cat.physicsBody?.dynamic = true
        cat.physicsBody?.allowsRotation = false

        cat.physicsBody?.categoryBitMask = catCategory
        cat.physicsBody?.collisionBitMask = worldCategory | obstCategory
        cat.physicsBody?.contactTestBitMask = worldCategory | obstCategory

        self.addChild(cat)

        var ground = SKNode()
        ground.position = CGPointMake(0, TextureG.size().height)
        ground.physicsBody = SKPhysicsBody(rectangleOfSize: CGSizeMake(self.frame.size.width, TextureG.size().height * 2.0))
        ground.physicsBody?.dynamic = false
        ground.physicsBody?.categoryBitMask = worldCategory
        self.addChild(ground)


        score = 0
        scoreLabelNode = SKLabelNode(fontNamed:"Font")
        scoreLabelNode.position = CGPointMake( CGRectGetMidX( self.frame ), 3 * self.frame.size.height / 4 )
        scoreLabelNode.zPosition = 100
        scoreLabelNode.text = String(score)
        self.addChild(scoreLabelNode)

    }

    func spawnObsts() {
        let obstPair = SKNode()
        obstPair.position = CGPointMake( self.frame.size.width + obstTextureUp.size().width * 2, 0 )
        obstPair.zPosition = -10

        let height = UInt32( self.frame.size.height / 4 )
        let y = arc4random() % height + height

        let obstDown = SKSpriteNode(texture: obstTextureDown)
        obstDown.setScale(2.0)
        obstDown.position = CGPointMake(0.0, CGFloat(y) + obstDown.size.height + CGFloat(verticalObstGap))


        obstDown.physicsBody = SKPhysicsBody(rectangleOfSize: obstDown.size)
        obstDown.physicsBody?.dynamic = false
        obstDown.physicsBody?.categoryBitMask = obstCategory
        obstDown.physicsBody?.contactTestBitMask = catCategory
        obstPair.addChild(obstDown)

        let obstUp = SKSpriteNode(texture: obstTextureUp)
        obstUp.setScale(2.0)
        obstUp.position = CGPointMake(0.0, CGFloat(y))

        obstUp.physicsBody = SKPhysicsBody(rectangleOfSize: obstUp.size)
        obstUp.physicsBody?.dynamic = false
        obstUp.physicsBody?.categoryBitMask = obstCategory
        obstUp.physicsBody?.contactTestBitMask = catCategory
        obstPair.addChild(obstUp)

        var contactNode = SKNode()
        contactNode.position = CGPointMake( obstDown.size.width + cat.size.width / 2, CGRectGetMidY( self.frame ) )
        contactNode.physicsBody = SKPhysicsBody(rectangleOfSize: CGSizeMake( obstUp.size.width, self.frame.size.height ))
        contactNode.physicsBody?.dynamic = false
        contactNode.physicsBody?.categoryBitMask = scoreCategory
        contactNode.physicsBody?.contactTestBitMask = catCategory
        obstPair.addChild(contactNode)

        obstPair.runAction(moveObstsAndRemove)
        obsts.addChild(pipePair)

    }

    func resetScene (){

        cat.position = CGPointMake(self.frame.size.width / 2.5, CGRectGetMidY(self.frame))
        cat.physicsBody?.velocity = CGVectorMake( 0, 0 )
        cat.physicsBody?.collisionBitMask = worldCategory | obstCategory
        cat.speed = 1.0
        cat.zRotation = 0.0

        obsts.removeAllChildren()

        canRestart = false

        score = 0
        scoreLabelNode.text = String(score)
        moving.speed = 1
    }

    override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {

        if moving.speed > 0  {
            for touch: AnyObject in touches {
                let location = touch.locationInNode(self)

                runAction(SKAction.playSoundFileNamed("sound.wav", waitForCompletion: false))
                cat.physicsBody?.velocity = CGVectorMake(0, 0)
                cat.physicsBody?.applyImpulse(CGVectorMake(0, 30))

            }
        }else if canRestart {
            self.resetScene()
        }

    }

    func clamp(min: CGFloat, max: CGFloat, value: CGFloat) -> CGFloat {
        if( value > max ) {
            return max
        } else if( value < min ) {
            return min
        } else {
            return value
        }
    }


    override func update(currentTime: CFTimeInterval) {

        cat.zRotation = self.clamp( -1, max: 0.5, value: cat.physicsBody!.velocity.dy * ( cat.physicsBody!.velocity.dy < 0 ? 0.003 : 0.001 ) )

    }

    func didBeginContact(contact: SKPhysicsContact) {
        if moving.speed > 0 {
            if ( contact.bodyA.categoryBitMask & scoreCategory ) == scoreCategory || ( contact.bodyB.categoryBitMask & scoreCategory ) == scoreCategory {


                score++
                scoreLabelNode.text = String(score)


                scoreLabelNode.runAction(SKAction.sequence([SKAction.scaleTo(1.5, duration:NSTimeInterval(0.7)), SKAction.scaleTo(1.0, duration:NSTimeInterval(0.1))]))
            } else {

                moving.speed = 0

                cat.physicsBody?.collisionBitMask = worldCategory
                cat.runAction(  SKAction.rotateByAngle(CGFloat(M_PI) * CGFloat(cat.position.y) * 0.01, duration:1), completion:{self.cat.speed = 0 })
                runAction(SKAction.playSoundFileNamed("sound2.wav", waitForCompletion: false))



                self.removeActionForKey("flash")
                self.runAction(SKAction.sequence([SKAction.repeatAction(SKAction.sequence([SKAction.runBlock({
                    self.backgroundColor = SKColor(red: 0.2, green: 1, blue: 0.1, alpha: 1.0)
                }),SKAction.waitForDuration(NSTimeInterval(0.05)), SKAction.runBlock({
                    self.backgroundColor = self.skyColor
                }), SKAction.waitForDuration(NSTimeInterval(0.05))]), count:4), SKAction.runBlock({
                    self.canRestart = true
                })]), withKey: "flash")
            }
        }
    }
}

---

这将防止接触和重力被应用，直到你按下播放按钮

将设置为零以暂停模拟。将其设置回1以恢复正常速度模拟。

什么是“声明物理世界”？场景的physicsWorld属性为只读。场景根据需要创建世界。基本上，设置物理世界，包括重力和其他属性。@robmayoff override func touchesBegantouches:NSSet，withEvent-event:UIEvent{if moving.speed>0{for touch:touch中的任何对象{let location=touch.locationInNodeself runActionSKAction.playSoundFileNamedsound.wav，waitForCompletion:false sprite.physicsBody？.velocity=CGVectorMake0,0 sprite.physicsBody？.applyImpulseCGVectorMake0,30}否则，如果可以重新启动{self.resetScene}@robmayoff现在我将把完整的代码复制到一个新问题上，并在那里标记你。希望你们能帮助我：@AndriyZherebyatyev不要问新问题；编辑你现有的问题。你忽略了他问如何使用按钮的部分。不，我假设他知道如何连接按钮，但不知道如何暂停模拟。

override func touchesEnded(touches: NSSet, withEvent event: UIEvent) {

    for touch: AnyObject in touches {
        let location = touch.locationInNode(self)

        if(playButton contains:location)
        {
             //Remove this code from your didMoveToView
             self.physicsWorld.gravity = CGVectorMake( 0.0, -6.3 )
             self.physicsWorld.contactDelegate = self
             [playButton removeFromParent]
        }
     }