     //MARK: Getters
     
     /// The color for a normal state.
+    ///
+    /// returns: The normal background color
     public func normalBackgroundColor() -> UIColor?
     {
         return objc_getAssociatedObject(self, &BackgroundColorNormal) as? UIColor
     }
+    
     /// The color for a highlighted state.
+    ///
+    /// returns: The highlighted background color.
     public func highlightedBackgroundColor() -> UIColor?
     {
         return objc_getAssociatedObject(self, &BackgroundColorHighlighted) as? UIColor


    //MARK: ControlState
    
    override var highlighted: Bool
    {
        didSet


    //MARK: ButtonActions
    
    /**
     The button updates the background color after a Control Event TouchUpInside.
     
     - parameter sender: the button.
     */
    func buttonTouchUpInside(sender: UIButton)
    {
        sender.backgroundColor = normalBackgroundColor()
    }
    
    /**
     The button updates the background color after a Control Event TouchUpOutside.
     
     - parameter sender: the button.
     */
    func buttonTouchUpOutside(sender: UIButton)
    {
        sender.backgroundColor = normalBackgroundColor()
    }
    
    /**
     The button updates the background color after a Control Event TouchDown.
     
     - parameter sender: the button.
     */
    func buttonTouchDown(sender: UIButton)
    {
        sender.backgroundColor = highlightedBackgroundColor()
    }
    
    /**
     The button updates the background color after a Control Event TouchCancel.
     
     - parameter sender: the button.
     */
    func buttonTouchCancel(sender: UIButton)
    {
        sender.backgroundColor = normalBackgroundColor()
