当我转换到一个新场景时，该场景不再有效（一个过渡了）！

Question

这是我的代码......从触摸开始！

if nodeITapped.name == "leftButton" {
    leftb.alpha = 0.5
    let fadeInAction = SKAction.fadeOutWithDuration(1)
    leftb.runAction(fadeInAction)
    let sceneToMoveTo = MainScene(size: self.size)
    sceneToMoveTo.scaleMode = self.scaleMode
    let myTransition = SKTransition.fadeWithDuration(2)
    self.view!.presentScene(sceneToMoveTo, transition: myTransition)
}