     var monoMode: Bool = false
     var holdMode: Bool = false
     var keysHeld = [UIButton]()
+    var midiNotesHeld = [Int]()
     let blackKeys = [49, 51, 54, 56, 58, 61, 63, 66, 68, 70]
     
     var conductor = Conductor.sharedInstance

        }
        statusLabel.text = "Key(s) Released"
        keysHeld.removeAll(keepCapacity: false)
    }
   
}

                turnOffKey(lastKey)
            }
        }
        
        if holdMode {
            if keysHeld.contains(key) {
                turnOffKey(key)
                return
            }
        }
        
        turnOnKey(key)
    }
    
    @IBAction func keyReleased(sender: UIButton) {
        let key = sender
        
        if holdMode && monoMode {
           toggleMonoKeyHeld(key)

        } else if holdMode && !monoMode {
            toggleKeyHeld(key)
            
        } else {
            turnOffKey(key)
        }
        
        lastKey = key
    }
    
