@mui/material/useScrollTrigger/useScrollTrigger.js

Material UI is an open-source React component library that implements Google's Material Design. It's comprehensive and can be used in production out of the box.

"use strict";
'use client';

var _interopRequireWildcard = require("@babel/runtime/helpers/interopRequireWildcard").default;
Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = useScrollTrigger;
var React = _interopRequireWildcard(require("react"));
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,
    ...other
  } = options;
  const store = React.useRef();
  const [trigger, setTrigger] = React.useState(() => getTrigger(store, other));
  React.useEffect(() => {
    if (target === null) {
      return setTrigger(false);
    }
    const handleScroll = () => {
      setTrigger(getTrigger(store, {
        target,
        ...other
      }));
    };
    handleScroll(); // Re-evaluate trigger when dependencies change
    target.addEventListener('scroll', handleScroll, {
      passive: true
    });
    return () => {
      target.removeEventListener('scroll', handleScroll, {
        passive: true
      });
    };
    // See Option 3. https://github.com/facebook/react/issues/14476#issuecomment-471199055
    // TODO: uncomment once we enable eslint-plugin-react-compiler // eslint-disable-next-line react-compiler/react-compiler
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [target, getTrigger, JSON.stringify(other)]);
  return trigger;
}