@IBAction func buttonClick(sender: AnyObject) {

            let calendarVC = kConstantObj.SetIntialMainViewController("CalendarViewController")
            self.window?.rootViewController = calendarVC
            self.window?.makeKeyAndVisible()
            }

        if sender  == mounthButton {
               calendarVC.presentationMode(.MonthView)

        } else {

func presentationMode() -> CalendarMode {
            return CalendarMode.MonthView
        }