问发射器碰撞不起作用？

EN

if bodyA.categoryBitMask == 1 && bodyB.categoryBitMask == 3 || bodyA.categoryBitMask == 3 && bodyB.categoryBitMask == 1{
    print("END GAME")

dieexplostionNode = SKEmitterNode(fileNamed: "Explosion.sks"){
dieexplostionNode.targetNode = self 
//dieexplostionNode.position = player.position - no need for this!

// add 3 actions
let wait = SKAction.wait(forDuration: 2)
let addExplosion = SKAction.run {
    self.player.addChild(dieexplostionNode!)
}
let removeExplosion = SKAction.run {
        dieexplostionNode?.removeFromParent()
 }

// put them in a sequence.
let seq = SKAction.sequence([addExplosion,wait,removeExplosion])

// run the sequence
self.run(seq)

}