你好，我正在使用 Swift 开发一个 SpriteKit 游戏，目前只有两个场景，加载场景和游戏场景。游戏场景会在显示之前访问数据库以获取信息。游戏场景中的一切都很好。当我先进入加载场景而不是直接进入游戏场景时，我遇到了问题。通过回调，我告诉加载场景在完成数据库工作后呈现游戏场景。然而，当我尝试演示时，我遇到了 10 多个这样的大错误:

2015-11-12 09:48:33.880 SpaceAcademy[2373:764586] This application is modifying the autolayout engine from a background thread, which can lead to engine corruption and weird crashes. This will cause an exception in a future release. (followed by a bunch of random info)

现在，通过一些测试，我发现是我的 UIElement(例如按钮、 slider 和标签)导致了此问题。但是我将它们移到了 didMoveToView 函数中，所以我很困惑为什么它们仍然抛出错误，因为它们在“后台线程”中。

还有一点奇怪的是，这些并不是 fatal error 。我的控制台突然爆炸，UIElements 在延迟十秒后出现。还有一点奇怪的是，如果我点击我知道应该是按钮的地方，该功能仍然会被调用，就好像按钮确实在那里一样。

我将非常感谢一个解决方案来摆脱控制台爆炸，但更重要的是摆脱显示 UI 元素 的十秒延迟，谢谢!!

代码设置场景

let skView = view as! SKView
    skView.showsFPS = false
    skView.showsNodeCount = false
    skView.ignoresSiblingOrder = true

    let scene = GameScene(size: view.bounds.size)
    scene.scaleMode = SKSceneScaleMode.ResizeFill


    let loading = LoadingScene(size: view.bounds.size, newScene: scene)
    skView.presentScene(loading, transition: SKTransition.crossFadeWithDuration(1))

    scene.setEverythingUp(loading)

加载场景:

import Foundation
import SpriteKit

class LoadingScene:SKScene{
    var newScene:SKScene!
    var oldCount = 0
    var loadCount = 0{
    didSet{
        print(loadCount)
        if loadCount == 0{
            if oldCount == 1{
                self.view?.presentScene(newScene)
            }
        }
        oldCount = loadCount
    }
}

init(size: CGSize, newScene:SKScene) {
    self.newScene = newScene
    super.init(size: size)

}

required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}

override func didMoveToView(view: SKView) {
    self.backgroundColor = UIColor.blackColor()
    let imageArray = [
        SKTexture(imageNamed: "Loader/Loader1.png"),
        SKTexture(imageNamed: "Loader/Loader2.png"),
        SKTexture(imageNamed: "Loader/Loader3.png")
    ]

    let loader = SKSpriteNode(texture: imageArray[0])
    let animation = SKAction.animateWithTextures(imageArray, timePerFrame: 0.33)
    loader.runAction(SKAction.scaleBy(0.25, duration: 0))
    loader.zPosition = 100
    loader.runAction(SKAction.repeatActionForever(animation))
    loader.position = CGPointMake(self.size.width/2, self.size.height/2)
    self.addChild(loader)
}

func start(){
    self.loadCount = self.loadCount + 1
}

func end(){
    self.loadCount = self.loadCount - 1
}

}

来自 GameScene 的代码:

func setEverythingUp(myLoadingScene: LoadingScene){

    let defaults: NSUserDefaults = NSUserDefaults.standardUserDefaults()

    var Id = 0
    if let tempID = defaults.objectForKey("UserId") as? Int {
       Id = tempID
    }else{
        print("newUser")
        defaults.setObject(0, forKey: "UserId")
        defaults.synchronize()
    }

    self.mySettings = Settings(UserId: Id)
    self.myURLRequests = URLRequests(thesettings: self.mySettings)

    ///////////call back system here, start() increments number of tasks waiting to finish, end() means a task is finished

    myLoadingScene.start()
    myURLRequests.getFleet(self, UserId: self.mySettings.UserId, enemy: false){ () -> () in
        myLoadingScene.end()
    }

    myLoadingScene.start()
    myURLRequests.getFleet(self, UserId: self.mySettings.UserId, enemy: true){ () -> () in
        myLoadingScene.end()
    }



    self.backgroundColor = SKColor.blackColor()
    self.physicsWorld.contactDelegate = self
    self.physicsWorld.gravity = CGVector(dx: 0, dy: 0)
    addStars()


    self.anchorPoint = CGPoint(x:self.size.width/2, y:self.size.height/2)
    self.myCamera.position = CGPointMake(200, 0)
    self.addChild(self.myCamera)
    self.camera = self.myCamera
    self.myAnchor.position = self.myCamera.position
}



override func didMoveToView(view: SKView) {
    print("in view")

    let pinch = UIPinchGestureRecognizer(target: self, action: Selector("PinchScale:"))
    let tap = UITapGestureRecognizer(target: self, action: Selector("Tap:"))
    let pan = UIPanGestureRecognizer(target: self, action: Selector("DragMove:"))

    self.view?.addGestureRecognizer(pinch)
    self.view?.addGestureRecognizer(tap)
    self.view?.addGestureRecognizer(pan)


    let fireButton = UIButton(type: .System)
    fireButton.setTitle("Fire!", forState: UIControlState.Normal)
    fireButton.titleLabel!.font = UIFont(name: "TrebuchetMS", size: 70)
    fireButton.sizeToFit()
    fireButton.frame = CGRect(x: self.size.width*0.5 - 80, y: 20, width: self.size.width*0.3, height: 30)
    fireButton.addTarget(self, action: Selector("FireButtonClicked"), forControlEvents: UIControlEvents.TouchUpInside)
    self.view?.addSubview(fireButton)

    let alternateControls = false

    let AngleLabel = UILabel()
    AngleLabel.text = "Angle"
    AngleLabel.font = UIFont(name: "TrebuchetMS", size: 30)
    AngleLabel.textColor = UIColor.blueColor()


    let AngleSlider = UISlider()
    AngleSlider.addTarget(self, action: Selector("AngleSlided:"), forControlEvents: UIControlEvents.ValueChanged)
    AngleSlider.maximumValue = 90
    AngleSlider.minimumValue = -90
    AngleSlider.value = 0
    AngleSlider.continuous = true



    let PowerLabel = UILabel()
    PowerLabel.text = "Power"
    PowerLabel.font = UIFont(name: "TrebuchetMS", size: 30)
    PowerLabel.textColor = UIColor.blueColor()


    let PowerSlider = UISlider()
    PowerSlider.addTarget(self, action: Selector("PowerSlided:"), forControlEvents: UIControlEvents.ValueChanged)
    PowerSlider.maximumValue = 0.99
    PowerSlider.minimumValue = 0.1
    PowerSlider.value = 0.5
    PowerSlider.continuous = true


    if alternateControls{
        AngleLabel.frame = CGRect(x: self.size.width*0.05, y: 10, width: self.size.width*0.3, height: 60)
        AngleSlider.frame = CGRect(x: self.size.width * -0.05, y: self.size.height*0.55, width: self.size.height*0.7, height: 30)
        AngleSlider.transform = CGAffineTransformMakeRotation(CGFloat(M_PI) * 1.5)
        PowerLabel.frame = CGRect(x: self.size.width*0.7, y: 10, width: self.size.width*0.3, height: 60)
        PowerSlider.frame = CGRect(x: self.size.width * 0.65, y: self.size.height*0.55, width: self.size.height*0.7, height: 30)
        PowerSlider.transform = CGAffineTransformMakeRotation(CGFloat(M_PI) * 1.5)
    }else{
        AngleLabel.frame = CGRect(x: self.size.width*0.21, y: self.size.height-80, width: self.size.width*0.3, height: 60)
        AngleSlider.frame = CGRect(x: self.size.width * 0.025, y: self.size.height-30, width: self.size.width*0.45, height: 30)
        PowerLabel.frame = CGRect(x: self.size.width*0.71, y: self.size.height-80, width: self.size.width*0.3, height: 60)
        PowerSlider.frame = CGRect(x: self.size.width * 0.525, y: self.size.height-30, width: self.size.width*0.45, height: 30)
    }

    self.view?.addSubview(AngleLabel)
    self.view?.addSubview(AngleSlider)
    self.view?.addSubview(PowerLabel)
    self.view?.addSubview(PowerSlider)

}

最佳答案

你这样做:

myURLRequests.getFleet(self, UserId: self.mySettings.UserId, enemy: false){ () -> () in
    myLoadingScene.end()
}

这可能会在 URL 请求完成后在后台线程上调用 myLoadingScene.end()。 end 设置loadCount，其中有一个启动新 View 的setter，self.view?.presentScene(newScene)

这是最后一 block 需要在主线程上运行。

假设您有一个方便的函数可以在主线程上运行一些东西:

func on_main_async (closure:()->()) {
    dispatch_async(dispatch_get_main_queue()) {
        closure()
    }
}

然后你可以将场景呈现代码更改为

on_main_async() { self.view?.presentScene(newScene) }

应该可以解决问题。

关于ios - SpriteKit 在转换到新场景时收到有关 UIElements 的错误，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/33677109/