weekLabel: 'W',
            customRangeLabel: 'Custom Range',
            daysOfWeek: moment.weekdaysMin(),
            monthNames: moment.monthsShort(),
            firstDay: moment.localeData().firstDayOfWeek()
        };

        this.callback = function() { };

        //some state information
        this.isShowing = false;
        this.leftCalendar = {};
        this.rightCalendar = {};