     static let minNumberOfKeys = 12
     static let maxNumberOfKeys = 61
     
-    weak var delegate:GLNPianoViewDelegate?
     var keyDown = NSMutableArray(capacity:maxNumberOfKeys)
     var keyRects = NSMutableArray(capacity:maxNumberOfKeys)
     var keyLayers = NSMutableArray(capacity:maxNumberOfKeys)

    var keyCornerRadius:CGFloat = 0
    var whiteKeyCount = 0
    
    
    override public init(frame: CGRect) {
        super.init(frame: frame)

import UIKit
import QuartzCore

public protocol GLNPianoViewDelegate: class  {
    func pianoKeyUp(_ keyNumber:UInt8)
    func pianoKeyDown(_ keyNumber:UInt8)
}

@IBDesignable public class GLNPianoView : UIView {
