acud/es/virtual-list/hooks/useFrameWheel.js

acg react 组件库

import { useRef } from 'react';
import raf from "rc-util/es/raf";
import isFF from '../utils/isFirefox';
import useOriginScroll from './useOriginScroll';
export default function useFrameWheel(inVirtual, isScrollAtTop, isScrollAtBottom, onWheelDelta) {
  var offsetRef = useRef(0);
  var nextFrameRef = useRef(null);
  // Firefox patch
  var wheelValueRef = useRef(null);
  var isMouseScrollRef = useRef(false);
  // Scroll status sync
  var originScroll = useOriginScroll(isScrollAtTop, isScrollAtBottom);
  function onWheel(event) {
    if (!inVirtual) return;
    raf.cancel(nextFrameRef.current);
    var deltaY = event.deltaY;
    offsetRef.current += deltaY;
    wheelValueRef.current = deltaY;
    // Do nothing when scroll at the edge, Skip check when is in scroll
    if (originScroll(deltaY)) return;
    // Proxy of scroll events
    if (!isFF) {
      event.preventDefault();
    }
    nextFrameRef.current = raf(function () {
      // Patch a multiple for Firefox to fix wheel number too small
      // ref: https://github.com/ant-design/ant-design/issues/26372#issuecomment-679460266
      var patchMultiple = isMouseScrollRef.current ? 10 : 1;
      onWheelDelta(offsetRef.current * patchMultiple);
      offsetRef.current = 0;
    });
  }
  // A patch for firefox
  function onFireFoxScroll(event) {
    if (!inVirtual) return;
    isMouseScrollRef.current = event.detail === wheelValueRef.current;
  }
  return [onWheel, onFireFoxScroll];
}