react-bootstrap-typeahead/es/components/Hint/Hint.js

React typeahead with Bootstrap styling

import React, { useEffect, useRef } from 'react';
import { useTypeaheadContext } from '../../core/Context';

// IE doesn't seem to get the composite computed value (eg: 'padding',
// 'borderStyle', etc.), so generate these from the individual values.
function interpolateStyle(styles, attr) {
  var subattr = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : '';
  // Title-case the sub-attribute.
  if (subattr) {
    /* eslint-disable-next-line no-param-reassign */
    subattr = subattr.replace(subattr[0], subattr[0].toUpperCase());
  }
  return ['Top', 'Right', 'Bottom', 'Left'].map(function (dir) {
    return styles["".concat(attr).concat(dir).concat(subattr)];
  }).join(' ');
}
function copyStyles(inputNode, hintNode) {
  var inputStyle = window.getComputedStyle(inputNode);

  /* eslint-disable no-param-reassign */
  hintNode.style.borderStyle = interpolateStyle(inputStyle, 'border', 'style');
  hintNode.style.borderWidth = interpolateStyle(inputStyle, 'border', 'width');
  hintNode.style.fontSize = inputStyle.fontSize;
  hintNode.style.fontWeight = inputStyle.fontWeight;
  hintNode.style.height = inputStyle.height;
  hintNode.style.lineHeight = inputStyle.lineHeight;
  hintNode.style.margin = interpolateStyle(inputStyle, 'margin');
  hintNode.style.padding = interpolateStyle(inputStyle, 'padding');
  /* eslint-enable no-param-reassign */
}

export var useHint = function useHint() {
  var _useTypeaheadContext = useTypeaheadContext(),
    hintText = _useTypeaheadContext.hintText,
    inputNode = _useTypeaheadContext.inputNode;
  var hintRef = useRef(null);
  useEffect(function () {
    // Scroll hint input when the text input is scrolling.
    var handleInputScroll = function handleInputScroll() {
      if (hintRef.current && inputNode) {
        hintRef.current.scrollLeft = inputNode.scrollLeft;
      }
    };
    inputNode === null || inputNode === void 0 || inputNode.addEventListener('scroll', handleInputScroll);
    return function () {
      inputNode === null || inputNode === void 0 || inputNode.removeEventListener('scroll', handleInputScroll);
    };
  }, [inputNode]);
  useEffect(function () {
    if (inputNode && hintRef.current) {
      copyStyles(inputNode, hintRef.current);
    }
  });
  return {
    hintRef: hintRef,
    hintText: hintText
  };
};
var Hint = function Hint(_ref) {
  var children = _ref.children,
    className = _ref.className;
  var _useHint = useHint(),
    hintRef = _useHint.hintRef,
    hintText = _useHint.hintText;
  return /*#__PURE__*/React.createElement("div", {
    className: className,
    style: {
      display: 'flex',
      flex: 1,
      height: '100%',
      position: 'relative'
    }
  }, children, /*#__PURE__*/React.createElement("input", {
    "aria-hidden": true,
    className: "rbt-input-hint",
    ref: hintRef,
    readOnly: true,
    style: {
      backgroundColor: 'transparent',
      borderColor: 'transparent',
      boxShadow: 'none',
      color: 'rgba(0, 0, 0, 0.54)',
      left: 0,
      pointerEvents: 'none',
      position: 'absolute',
      top: 0,
      width: '100%'
    },
    tabIndex: -1,
    value: hintText
  }));
};
export default Hint;