     }
 
     override func viewDidAppear(_ animated: Bool) {
-    }
-}
-
-extension Array where Element == Bool {
-    var nsArray: [NSNumber] {
-        return self.map{ NSNumber(value:$0) }
     }
 }
 

    }
}

extension ViewController: AudioEngineIFProtocol {
    func audioEngine(_ engine: AudioEngineIF,
        didTriggeredTracks tracks: [NSNumber],
        step stepNo: Int32,
        atTime absoluteTime: UInt64)
    {
        print("\(tracks)")
        DispatchQueue.main.async {
        }
    }
}


        bpmSliderUpdated(_bpmSlider)
        stepSliderUpdated(_stepSlider)

        _engine.onTriggerdCallback = {
            (tracks: [Int], stepNo: Int, absoluteTime: UInt64) in
            print("\(absoluteTime): <\(stepNo)> \(tracks)")
        }
    }

    override func didReceiveMemoryWarning() {
