为什么我在 Swift 中不断收到此错误？ 'Attemped to add a SKNode which already has a parent'

Question

我试图让这个矩形重复，但我一直收到这样的错误消息。我尝试了一切，但我似乎无法弄清楚。有人可以帮忙吗？太令人沮丧了，我无法通过这一部分。我已经被这个错误困住了几天了。如果您需要更多信息，请给我发消息。

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: Attemped to add a SKNode which already has a parent: >name:'(null)' texture:[ 'longrec'

class GameScene: SKScene, SKPhysicsContactDelegate {
    let longRec = SKSpriteNode(imageNamed: "longrec")


   override func didMoveToView(view: SKView) {
       repeatlongRec()
   }

   func longRec() {
    let moveToTheLeft = SKAction.moveByX(-self.size.width, y: 0, duration: 2.0)
    let repeatMoveToLeft = SKAction.repeatActionForever(moveToTheLeft)
    let removeFromScene = SKAction.removeFromParent()
    let sequence = SKAction.sequence([repeatMoveToLeft, removeFromScene])


    longRec.position = CGPointMake(self.size.width / 0.5, self.size.height / 2)
    longRec.zPosition = 15
    longRec.runAction(sequence)
    addChild(longRec)        
    }

   func repeatlongRec() {
   let generateLongRec = SKAction.sequence([
   SKAction.runBlock(self.longRec),
   SKAction.waitForDuration(2.0)])
   let endlessAction = SKAction.repeatAction(generateLongRec, count: 4)
   runAction(endlessAction)
   }
}

Answer 1

在你执行 addChild(longRec) 之后你永远不会删除它

因此，当您执行 func repeatlongRec() 时，它会崩溃，因为该节点仍然存在。

尝试重组这两个函数，以便在不使用节点时删除节点，然后重复该过程

Answer 2

试试下面的代码：

import SpriteKit

class GameScene: SKScene, SKPhysicsContactDelegate {

    let longRec = SKSpriteNode(imageNamed: "rectangle.png")

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

        let makeLongRec = SKAction.sequence([SKAction.runBlock(generateLongRec), SKAction.waitForDuration(3)])
        runAction(SKAction.repeatAction(makeLongRec, count: 4))
    }

    func generateLongRec() {

        longRec.position = CGPointMake(self.size.width / 2, self.size.height / 2)
        longRec.zPosition = 15
        self.addChild(longRec)
        let moveToTheLeft = SKAction.moveByX(-self.size.width, y: 0, duration: 2.0)
        let removeFromScene = SKAction.removeFromParent()
        longRec.runAction(SKAction.sequence([moveToTheLeft, removeFromScene]))
    }

您的代码存在问题，添加速度太快。就像@Ace Green 所说的那样，您甚至在删除节点之前就添加了该节点。

另外两件事你应该知道：

尽量不要为 func 和您的节点使用相同的名称。
如果您打算只使用一个节点并重复添加它。 didMoveToView 中 waitforDuration(2) 中的等待时间应始终大于 let moveToTheLeft = SKAction.moveByX(-self.size.width, y: 0, duration: 2.0) 中的持续时间，否则你仍然会遇到相同的 Attemped to add a SKNode which already has a parent 问题。解决这个问题的一种方法是声明一个节点数组。

Answer 3

我会尝试这样做：

class GameScene: SKScene, SKPhysicsContactDelegate {

   let longRec = SKSpriteNode(imageNamed: "longrec")

   override func didMoveToView(view: SKView) {

       var timer = NSTimer .scheduledTimerWithTimeInterval(2, target: self, selector: Selector("longRec") , userInfo: nil, repeats: true)

   }

   func longRec() {
    let moveToTheLeft = SKAction.moveByX(-self.size.width, y: 0, duration: 2.0)
    let removeFromScene = SKAction.removeFromParent()
    let sequence = SKAction.sequence([moveToTheLeft, removeFromScene])
    let repeatSequence = SKAction.repeatActionForever(sequence)

    longRec.position = CGPointMake(self.size.width / 0.5, self.size.height / 2)
    longRec.zPosition = 15

    longRec.runAction(repeatSequence)   

    addChild(longRec) 

    }
}

为什么我在 Swift 中不断收到此错误？ 'Attemped to add a SKNode which already has a parent'

Why do I keep getting this error in Swift? 'Attemped to add a SKNode which already has a parent'

sprite-kit

skaction

swift