setValueAt(index, value) {
    // temporary solution to avoid input reset
    // on invalid date.
    if (value === 'Invalid date') {
      return null;
    }
    let day, month, year;
    const parts = value.split('/');

    if (parts.length !== 3) {
      day = this.getDayWithHiddenFields(parts).day;
      month = this.getDayWithHiddenFields(parts).month;
      year = this.getDayWithHiddenFields(parts).year;
    }
    else {
      if (this.component.dayFirst) {
        day = parts.shift();
      }
      month = parts.shift();
      if (!this.component.dayFirst) {
        day = parts.shift();
      }
      year = parts.shift();
    }
    if (this.refs.day && this.showDay) {
      this.refs.day.value = day === '00' ? '' : parseInt(day, 10);
    }
    if (this.refs.month && this.showMonth) {
      this.refs.month.value = month === '00' ? '' : parseInt(month, 10);
    }
    if (this.refs.year && this.showYear) {
      this.refs.year.value = year === '0000' ? '' : parseInt(year, 10);
    }
  }
Set the value at a specific index and updates the component's refs.
@param {number} index - The index to set.
@param {any} value - The value to set.
@returns {null|void} - Returns null if the value is invalid, otherwise void.