Swift Xcodeでの衝突の設定

Question

私はこのエラーに遭遇したときに、迅速に衝突を設定する過程にあります。私はそのエラーを修正するためにコード行を変更することができますが、それを行うと、より多くのエラーが発生します。

let collisionHitBox = CGRect(x: 201, y: 139, width: 398, height: 212) 

barCollisions.physicsBody? = SKPhysicsBody(edgeLoopFromRect: collisionHitBox) 

    let ballCategory: UInt32 = 0x1 << 0 
    let barCategory: UInt32 = 0x1 << 1 

    ball.physicsBody?.categoryBitMask = ballCategory 
    ball.physicsBody?.usesPreciseCollisionDetection = true 
    ball.physicsBody?.collisionBitMask = ballCategory | barCategory 
    ball.physicsBody?.contactTestBitMask = ballCategory | barCategory 

    barCollisions.physicsBody?.categoryBitMask = barCategory 
    barCollisions.physicsBody?.usesPreciseCollisionDetection = true 






    func didBeginContact(contact: SKPhysicsContact) { 
     let firstNode = contact.bodyA.node as! SKSpriteNode 
     // This is where I get an error saying "Initialization of immutable value was never used, consider replacing it for removing it"  

     let secondNode = contact.bodyB.node as! SKSpriteNode 

     if (contact.bodyA.categoryBitMask == ballCategory) && (contact.bodyB.categoryBitMask == barCategory) 
     { 
      let contactPoint = contact.contactPoint 
      let contact_y = contactPoint.y 
      let target_y = secondNode.position.y 
      let margin = secondNode.frame.size.height/2 - 25 
      if (contact_y > (target_y - margin)) && contact_y < (target_y + margin) { 

       print("GameOver") 


      } 
     } 

Answer 1

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