WinRTXamlToolkit.Controls.Calendar.OnHeaderClick C# (CSharp) Method

        internal void OnHeaderClick()
        {
            Debug.Assert(DisplayMode == CalendarMode.Year || DisplayMode == CalendarMode.Decade, "The DisplayMode should be Year or Decade");
            CalendarItem monthControl = MonthControl;
            if (monthControl != null && monthControl.MonthView != null && monthControl.YearView != null)
            {
                monthControl.MonthView.Visibility = Visibility.Collapsed;
                monthControl.YearView.Visibility = Visibility.Visible;
                UpdateMonths();
            }
        }