Tread 1：EXC_BAD_ACCESS（代码= EXC_1386_GPFLT）

Question

我真的很喜欢编程，并且通过组合来自许多不同教程的代码来开发iPhone游戏。

我在游戏场景中添加了score和highScore，我想在mainMenu场景中显示highScore。

该应用程序运行一段时间，但有时当我回到主菜单场景时，应用程序崩溃：

  

（Thread1：EXC_BAD_ACCESS（code = EXC_1386_GPFLT）

Screenshot of the crash

import SpriteKit
import AVFoundation

var playicon:SKSpriteNode!
var logo:SKSpriteNode!

var settingicon = SKSpriteNode()
var infoicon = SKSpriteNode()
var facebookbtn = SKSpriteNode()
var highScoreLbl = SKLabelNode()
var highScore = Int()
var highscorebg = SKSpriteNode()


var backgroundMusicPlayer = AVAudioPlayer()

class MainMenu: SKScene {         

override func didMoveToView(view: SKView) {

 let HighscoreDefault = NSUserDefaults.standardUserDefaults()

    if (HighscoreDefault.valueForKey("highscore") != nil) {
        highScore = HighscoreDefault.valueForKey("highscore") as! NSInteger
       highScoreLbl.text = "\(highScore)"
    }

    highScoreLbl.position = CGPoint(x: self.frame.width / 2 + 80, y: self.frame.height / 2 - 20)
    highScoreLbl.zPosition = 4
    highScoreLbl.setScale(0)
    highScoreLbl.fontName = "Skater Girls Rock"
    highScoreLbl.fontSize = 100

    self.addChild(highScoreLbl)
    highScoreLbl.runAction(SKAction.scaleTo(1, duration: 0.3))
}

}