@mui/material/node/useScrollTrigger/useScrollTrigger.js

Quickly build beautiful React apps. MUI is a simple and customizable component library to build faster, beautiful, and more accessible React applications. Follow your own design system, or start with Material Design.

"use strict";

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = useScrollTrigger;

var _extends2 = _interopRequireDefault(require("@babel/runtime/helpers/extends"));

var _objectWithoutPropertiesLoose2 = _interopRequireDefault(require("@babel/runtime/helpers/objectWithoutPropertiesLoose"));

var React = _interopRequireWildcard(require("react"));

const _excluded = ["getTrigger", "target"];

function _getRequireWildcardCache(nodeInterop) { if (typeof WeakMap !== "function") return null; var cacheBabelInterop = new WeakMap(); var cacheNodeInterop = new WeakMap(); return (_getRequireWildcardCache = function (nodeInterop) { return nodeInterop ? cacheNodeInterop : cacheBabelInterop; })(nodeInterop); }

function _interopRequireWildcard(obj, nodeInterop) { if (!nodeInterop && obj && obj.__esModule) { return obj; } if (obj === null || typeof obj !== "object" && typeof obj !== "function") { return { default: obj }; } var cache = _getRequireWildcardCache(nodeInterop); if (cache && cache.has(obj)) { return cache.get(obj); } var newObj = {}; var hasPropertyDescriptor = Object.defineProperty && Object.getOwnPropertyDescriptor; for (var key in obj) { if (key !== "default" && Object.prototype.hasOwnProperty.call(obj, key)) { var desc = hasPropertyDescriptor ? Object.getOwnPropertyDescriptor(obj, key) : null; if (desc && (desc.get || desc.set)) { Object.defineProperty(newObj, key, desc); } else { newObj[key] = obj[key]; } } } newObj.default = obj; if (cache) { cache.set(obj, newObj); } return newObj; }

function defaultTrigger(store, options) {
  const {
    disableHysteresis = false,
    threshold = 100,
    target
  } = options;
  const previous = store.current;

  if (target) {
    // Get vertical scroll
    store.current = target.pageYOffset !== undefined ? target.pageYOffset : target.scrollTop;
  }

  if (!disableHysteresis && previous !== undefined) {
    if (store.current < previous) {
      return false;
    }
  }

  return store.current > threshold;
}

const defaultTarget = typeof window !== 'undefined' ? window : null;

function useScrollTrigger(options = {}) {
  const {
    getTrigger = defaultTrigger,
    target = defaultTarget
  } = options,
        other = (0, _objectWithoutPropertiesLoose2.default)(options, _excluded);
  const store = React.useRef();
  const [trigger, setTrigger] = React.useState(() => getTrigger(store, other));
  React.useEffect(() => {
    const handleScroll = () => {
      setTrigger(getTrigger(store, (0, _extends2.default)({
        target
      }, other)));
    };

    handleScroll(); // Re-evaluate trigger when dependencies change

    target.addEventListener('scroll', handleScroll);
    return () => {
      target.removeEventListener('scroll', handleScroll);
    }; // See Option 3. https://github.com/facebook/react/issues/14476#issuecomment-471199055
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [target, getTrigger, JSON.stringify(other)]);
  return trigger;
}