ant-design/components/grid/row.tsx

import classNames from 'classnames';
import * as React from 'react';
import { ConfigContext } from '../config-provider';
import useFlexGapSupport from '../_util/hooks/useFlexGapSupport';
import type { Breakpoint, ScreenMap } from '../_util/responsiveObserver';
import useResponsiveObserver, { responsiveArray } from '../_util/responsiveObserver';
import RowContext from './RowContext';
import { useRowStyle } from './style';

const RowAligns = ['top', 'middle', 'bottom', 'stretch'] as const;
const RowJustify = [
  'start',
  'end',
  'center',
  'space-around',
  'space-between',
  'space-evenly',
] as const;

type Responsive = 'xxl' | 'xl' | 'lg' | 'md' | 'sm' | 'xs';
type ResponsiveLike<T> = {
  [key in Responsive]?: T;
};

type Gap = number | undefined;
export type Gutter = number | undefined | Partial<Record<Breakpoint, number>>;

type ResponsiveAligns = ResponsiveLike<typeof RowAligns[number]>;
type ResponsiveJustify = ResponsiveLike<typeof RowJustify[number]>;
export interface RowProps extends React.HTMLAttributes<HTMLDivElement> {
  gutter?: Gutter | [Gutter, Gutter];
  align?: typeof RowAligns[number] | ResponsiveAligns;
  justify?: typeof RowJustify[number] | ResponsiveJustify;
  prefixCls?: string;
  wrap?: boolean;
}

function useMergePropByScreen(oriProp: RowProps['align'] | RowProps['justify'], screen: ScreenMap) {
  const [prop, setProp] = React.useState(typeof oriProp === 'string' ? oriProp : '');

  const calcMergeAlignOrJustify = () => {
    if (typeof oriProp === 'string') {
      setProp(oriProp);
    }
    if (typeof oriProp !== 'object') {
      return;
    }
    for (let i = 0; i < responsiveArray.length; i++) {
      const breakpoint: Breakpoint = responsiveArray[i];
      // if do not match, do nothing
      if (!screen[breakpoint]) continue;
      const curVal = oriProp[breakpoint];
      if (curVal !== undefined) {
        setProp(curVal);
        return;
      }
    }
  };

  React.useEffect(() => {
    calcMergeAlignOrJustify();
  }, [JSON.stringify(oriProp), screen]);

  return prop;
}

const Row = React.forwardRef<HTMLDivElement, RowProps>((props, ref) => {
  const {
    prefixCls: customizePrefixCls,
    justify,
    align,
    className,
    style,
    children,
    gutter = 0,
    wrap,
    ...others
  } = props;

  const { getPrefixCls, direction } = React.useContext(ConfigContext);

  const [screens, setScreens] = React.useState<ScreenMap>({
    xs: true,
    sm: true,
    md: true,
    lg: true,
    xl: true,
    xxl: true,
  });
  // to save screens info when responsiveObserve callback had been call
  const [curScreens, setCurScreens] = React.useState<ScreenMap>({
    xs: false,
    sm: false,
    md: false,
    lg: false,
    xl: false,
    xxl: false,
  });

  // ================================== calc responsive data ==================================
  const mergeAlign = useMergePropByScreen(align, curScreens);

  const mergeJustify = useMergePropByScreen(justify, curScreens);

  const supportFlexGap = useFlexGapSupport();