我在这里和其他网站上查了答案，但没有得到明确的解决方案。
我有两个场景
场景1：
class GameMenuScene: SKScene {
override func didMoveToView(view: SKView) {
// Add background
var background: SKSpriteNode = SKSpriteNode(imageNamed: "Starfield")
background.position = CGPointMake(-20, 0)
background.size = CGSizeMake(self.size.width + 40, self.size.height)
background.anchorPoint = CGPointZero
background.blendMode = SKBlendMode.Replace
self.addChild(background)
// Add game title
gameTitle = SKSpriteNode(imageNamed: "Title")
gameTitle.name = "Game Title"
gameTitle.xScale = scale
gameTitle.yScale = scale
gameTitle.position = CGPoint(x: CGRectGetMidX(self.frame), y: self.frame.height * 0.75)
self.addChild(gameTitle)
// Add scoreboard
scoreboard = SKSpriteNode(imageNamed: "ScoreBoard")
scoreboard.name = "Scoreboard"
scoreboard.xScale = scale
scoreboard.yScale = scale
scoreboard.position = CGPoint(x: CGRectGetMidX(self.frame), y: self.frame.height * 0.50)
self.addChild(scoreboard)
// Add play button
playButton = SKSpriteNode(imageNamed: "PlayButton")
playButton.name = "PlayButton"
playButton.xScale = scale
playButton.yScale = scale
playButton.position = CGPoint(x: CGRectGetMidX(self.frame), y: self.frame.height * 0.25)
self.addChild(playButton)
// Add menu score label
var menuScoreLabel = SKLabelNode()
menuScoreLabel.fontName = fontName
menuScoreLabel.fontSize = scoreFontsize
menuScoreLabel.text = String(score)
menuScoreLabel.position = CGPointMake(scoreboard.position.x - (scoreboard.size.width / 4), scoreboard.position.y - (scoreboard.size.height / 4))
menuScoreLabel.zPosition = 10
self.addChild(menuScoreLabel)
// Add menu top score label
var menuTopScoreLabel = SKLabelNode()
menuTopScoreLabel.fontName = fontName
menuTopScoreLabel.fontSize = scoreFontsize
menuTopScoreLabel.text = String(userDefaults.integerForKey("TopScore"))
menuTopScoreLabel.position = CGPointMake(scoreboard.position.x + (scoreboard.size.width / 4), scoreboard.position.y - (scoreboard.size.height / 4))
menuTopScoreLabel.zPosition = 10
self.addChild(menuTopScoreLabel)
}
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
/* Called when a touch begins */
for touch in (touches as! Set<UITouch>) {
// Get touch location
var touchLocation = touch.locationInNode(self)
// Check if Play button is presssed
if playButton.containsPoint(touchLocation) == true {
//println("right node touched")
// Transition to GameScene.swift
var transition: SKTransition = SKTransition.fadeWithDuration(1)
// Configure the view.
let scene = GameScene()
let skView = self.view! as SKView
skView.showsFPS = true
skView.showsNodeCount = true
/* Sprite Kit applies additional optimizations to improve rendering performance */
skView.ignoresSiblingOrder = true
/* Set the scale mode to scale to fit the window */
scene.size = skView.bounds.size
scene.scaleMode = .AspectFill
skView.presentScene(scene, transition: transition)
}
}
}
}
场景2：
类GameScene：SKScene，SKPhysicsContactDelegate {
override func didMoveToView(view: SKView) {
/* Setup your scene here */
// Add background
var background: SKSpriteNode = SKSpriteNode(imageNamed: "Starfield")
background.position = CGPointMake(-20, 0)
background.size = CGSizeMake(self.size.width + 40, self.size.height)
background.anchorPoint = CGPointZero
background.blendMode = SKBlendMode.Replace
self.addChild(background)
// Add mainlayer & labelHolderLayer
self.addChild(mainLayer)
self.addChild(labelHolderLayer)
// Add cannon
cannon = SKSpriteNode(imageNamed: "Cannon")
cannon.name = "Cannon"
cannon.position = CGPoint(x: CGRectGetMidX(self.frame), y: 0)
self.addChild(cannon)
// Add score label
scoreLabel.name = "Score Label"
scoreLabel.fontName = fontName
scoreLabel.fontSize = scoreFontsize
scoreLabel.text = String(score)
scoreLabel.position = CGPointMake(CGRectGetMidX(self.frame), self.frame.size.height - scoreFontsize)
scoreLabel.zPosition = 10
self.addChild(scoreLabel)
// Add LivesDisplay
livesDisplay = SKSpriteNode(imageNamed: "Ammo5")
livesDisplay.name = "livesDisplay"
livesDisplay.position = CGPoint(x: self.size.width - livesDisplay.size.width, y: self.size.height - livesDisplay.size.height)
self.addChild(livesDisplay)
// Settings for new game
newGame()
}
func gameIsOver() {
// Set game over flag and stop movement
gameOver = 1
mainLayer.speed = 0
mainLayer.paused = true
// Add game over label
gameOverLabel.fontName = fontName
gameOverLabel.fontSize = gameOverFontsize
gameOverLabel.text = "Game Over!"
gameOverLabel.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame))
gameOverLabel.zPosition = 10
labelHolderLayer.addChild(gameOverLabel)
// Set main menu top score
if score > userDefaults.integerForKey("TopScore") {
userDefaults.setInteger(score, forKey: "TopScore")
userDefaults.synchronize()
}
// Run acton sequence (wait a few seconds before transitioning)
runAction(SKAction.sequence([SKAction.waitForDuration(1), SKAction.runBlock({ () -> Void in
// Transition back to GameMenuScene
var transition: SKTransition = SKTransition.fadeWithDuration(1)
// Configure the view.
let scene = GameMenuScene()
let skView = self.view! as SKView
skView.showsFPS = true
skView.showsNodeCount = true
/* Sprite Kit applies additional optimizations to improve rendering performance */
skView.ignoresSiblingOrder = true
/* Set the scale mode to scale to fit the window */
scene.size = skView.bounds.size
scene.scaleMode = .AspectFill
skView.presentScene(scene, transition: transition)
})]))
}
}
当我最初启动应用程序时，我可以从场景1转换到场景2.当游戏结束时，应用程序转换回场景1.但是当我再次尝试转到场景2时，应用程序崩溃了。这只发生在设备上，在模拟器上，我可以来回移动而没有任何问题。
我得到的错误是正在添加已存在的SKNode。我知道这意味着什么，当我尝试
时错误就开始了 // Add mainlayer & labelHolderLayer
self.addChild(mainLayer)
self.addChild(labelHolderLayer)
但我不知道为什么它可以添加背景而没有任何问题，但从那里崩溃。另外为什么它可以在模拟器上工作，但不能在设备上工作？如果节点已经创建，我真的需要检查我的didMoveToView吗？
答案 0 :(得分：1)
我发现了我犯的错误。
我正在实例化我的场景2类之外的节点，使它们成为全局的。因此当我从场景1开始 - ＆gt;场景2 - ＆gt;场景1没有问题，但是再次进入场景2导致崩溃，因为节点是全局创建的。
<强>解决方案：
在类中移动以下代码解决了问题。
var mainLayer = SKSpriteNode()
var labelHolderLayer = SKSpriteNode()
var livesDisplay = SKSpriteNode()
var scoreLabel = SKLabelNode()