text: import * as React from 'react';
  import { isFragment } from 'react-is';
  import PropTypes from 'prop-types';
  import clsx from 'clsx';
  import withStyles from '../styles/withStyles';
  
  export const styles = (theme) => ({
    /* Styles applied to the root element. */
    root: {
      display: 'flex',
      justifyContent: 'center',
      height: 56,
      backgroundColor: theme.palette.background.paper,
    },
  });
  
  const BottomNavigation = React.forwardRef(function BottomNavigation(props, ref) {
    const {
      children,
      classes,
      className,
      component: Component = 'div',
      onChange,
      showLabels = false,
      value,
      ...other
    } = props;
  
    return (
      <Component className={clsx(classes.root, className)} ref={ref} {...other}>
        {React.Children.map(children, (child, childIndex) => {
          if (!React.isValidElement(child)) {
            return null;
          }
  
          if (process.env.NODE_ENV !== 'production') {
            if (isFragment(child)) {
              console.error(
                [
                  "Material-UI: The BottomNavigation component doesn't accept a Fragment as a child.",
                  'Consider providing an array instead.',
                ].join('\n'),
              );
            }
          }
  
          const childValue = child.props.value === undefined ? childIndex : child.props.value;
  
          return React.cloneElement(child, {
            selected: childValue === value,
            showLabel: child.props.showLabel !== undefined ? child.props.showLabel : showLabels,
            value: childValue,
            onChange,
          });
        })}
      </Component>
    );
  });
  
  BottomNavigation.propTypes = {
    // ----------------------------- Warning --------------------------------
    // | These PropTypes are generated from the TypeScript type definitions |
    // |     To update them edit the d.ts file and run "yarn proptypes"     |
    // ----------------------------------------------------------------------
    /**
     * The content of the component.
     */
    children: PropTypes.node,
    /**
     * Override or extend the styles applied to the component.
     * See [CSS API](#css) below for more details.
     */
    classes: PropTypes.object,
    /**
     * @ignore
     */
    className: PropTypes.string,
    /**
     * The component used for the root node.
     * Either a string to use a HTML element or a component.
     */
    component: PropTypes.elementType,
    /**
     * Callback fired when the value changes.
     *
     * @param {object} event The event source of the callback.
     * @param {any} value We default to the index of the child.
     */
    onChange: PropTypes.func,
    /**
     * If `true`, all `BottomNavigationAction`s will show their labels.
     * By default, only the selected `BottomNavigationAction` will show its label.
     */
    showLabels: PropTypes.bool,
    /**
     * The value of the currently selected `BottomNavigationAction`.
     */
    value: PropTypes.any,
  };
  
  export default withStyles(styles, { name: 'MuiBottomNavigation' })(BottomNavigation);
  