Function useSliderState

packages/react-stately/src/slider/useSliderState.ts:216–407

(
  props: SliderStateOptions<T>
)

 * @param props
 */
export function useSliderState<T extends number | number[]>(
  props: SliderStateOptions<T>
): SliderState {
  const {
    isDisabled = false,
    minValue = DEFAULT_MIN_VALUE,
    maxValue = DEFAULT_MAX_VALUE,
    numberFormatter: formatter,
    step = DEFAULT_STEP_VALUE,
    orientation = 'horizontal'
  } = props;

  // Page step should be at least equal to step and always a multiple of the step.
  let pageSize = useMemo(() => {
    let calcPageSize = (maxValue - minValue) / 10;
    calcPageSize = snapValueToStep(calcPageSize, 0, calcPageSize + step, step);
    return Math.max(calcPageSize, step);
  }, [step, maxValue, minValue]);

  let restrictValues = useCallback(
    (values: number[] | undefined) =>
      values?.map((val, idx) => {
        let min = idx === 0 ? minValue : values[idx - 1];
        let max = idx === values.length - 1 ? maxValue : values[idx + 1];
        return snapValueToStep(val, min, max, step);
      }),
    [minValue, maxValue, step]
  );

  let value = useMemo(
    () => restrictValues(convertValue(props.value)),
    [props.value, restrictValues]
  );
  let defaultValue = useMemo(
    () => restrictValues(convertValue(props.defaultValue) ?? [minValue])!,
    [props.defaultValue, minValue, restrictValues]
  );
  let onChange = createOnChange(props.value, props.defaultValue, props.onChange);
  let onChangeEnd = createOnChange(props.value, props.defaultValue, props.onChangeEnd);

  const [values, setValuesState] = useControlledState<number[]>(value, defaultValue, onChange);
  let [initialValues] = useState(values);
  const [isDraggings, setDraggingsState] = useState<boolean[]>(
    new Array(values.length).fill(false)
  );
  const isEditablesRef = useRef<boolean[]>(new Array(values.length).fill(true));
  const [focusedIndex, setFocusedIndex] = useState<number | undefined>(undefined);

  const valuesRef = useRef<number[]>(values);
  const isDraggingsRef = useRef<boolean[]>(isDraggings);

  let setValues = (values: number[]) => {
    valuesRef.current = values;
    setValuesState(values);
  };

  let setDraggings = (draggings: boolean[]) => {
    isDraggingsRef.current = draggings;