Method onPrevMonthTransition

src/components/DayPicker.jsx:546–572

(nextFocusedDate)

  }

  onPrevMonthTransition(nextFocusedDate) {
    const { daySize, isRTL, numberOfMonths } = this.props;
    const { calendarMonthWidth, monthTitleHeight } = this.state;

    let translationValue;
    if (this.isVertical()) {
      const calendarMonthWeeksHeight = this.calendarMonthWeeks[0] * (daySize - 1);
      translationValue = monthTitleHeight + calendarMonthWeeksHeight + 1;
    } else if (this.isHorizontal()) {
      translationValue = calendarMonthWidth;
      if (isRTL) {
        translationValue = -2 * calendarMonthWidth;
      }

      const visibleCalendarWeeks = this.calendarMonthWeeks.slice(0, numberOfMonths);
      const calendarMonthWeeksHeight = Math.max(0, ...visibleCalendarWeeks) * (daySize - 1);
      const newMonthHeight = monthTitleHeight + calendarMonthWeeksHeight + 1;
      this.adjustDayPickerHeight(newMonthHeight);
    }

    this.setState({
      monthTransition: PREV_TRANSITION,
      translationValue,
      focusedDate: null,
      nextFocusedDate,
    });
  }

  onMonthChange(currentMonth) {
    this.setCalendarMonthWeeks(currentMonth);