iOS 9のReplayKitでゲームプレー動画を撮影＆シェア：iOS SDKとSwiftで始めるゲーム作成入門（7）（2/4 ページ）

class Enemy: SKSpriteNode {
    var life = 0
}
 
// Enemy1〜3を追加
class Enemy1: Enemy {
    init() {
        super.init(texture: SKTexture(imageNamed: "Enemy1"), color: UIColor.clearColor(), size: CGSize(width: 32, height: 32))
        life = 3
    }
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}
 
class Enemy2: Enemy {
    init() {
        super.init(texture: SKTexture(imageNamed: "Enemy2"), color: UIColor.clearColor(), size: CGSize(width: 32, height: 32))
        life = 6
    }
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}
 
class Enemy3: Enemy {
    init() {
        super.init(texture: SKTexture(imageNamed: "Enemy3"), color: UIColor.clearColor(), size: CGSize(width: 32, height: 32))
        life = 9
    }
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

class EnemyFactory {
    func createEnemy() -> Enemy {
        return Enemy()
    }
}
 
class Enemy1Factory: EnemyFactory {
    override func createEnemy() -> Enemy {
        return Enemy1()
    }
}
 
class Enemy2Factory: EnemyFactory {
    override func createEnemy() -> Enemy {
        return Enemy2()
    }
}
 
class Enemy3Factory: EnemyFactory {
    override func createEnemy() -> Enemy {
        return Enemy3()
    }
}

class GameScene: SKScene, SKPhysicsContactDelegate {
    // 省略
 
    func createEnemy() {
        guard let view = view else {
            return
        }
 
        let enemy = enemyFactory().createEnemy() // この行を修正
 
        // 省略
    }
 
    func enemyFactory() -> EnemyFactory {
        switch stage {
        case 1: return Enemy1Factory()
        case 2: return Enemy2Factory()
        case 3: return Enemy3Factory()
        default: return EnemyFactory()
        }
    }
 
    // 省略
}