amis-rpc-design/node_modules/rc-virtual-list/es/hooks/useOriginScroll.js

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2023-10-07 19:42:30 +08:00
import { useRef } from 'react';
export default (function (isScrollAtTop, isScrollAtBottom) {
// Do lock for a wheel when scrolling
var lockRef = useRef(false);
var lockTimeoutRef = useRef(null);
function lockScroll() {
clearTimeout(lockTimeoutRef.current);
lockRef.current = true;
lockTimeoutRef.current = setTimeout(function () {
lockRef.current = false;
}, 50);
}
// Pass to ref since global add is in closure
var scrollPingRef = useRef({
top: isScrollAtTop,
bottom: isScrollAtBottom
});
scrollPingRef.current.top = isScrollAtTop;
scrollPingRef.current.bottom = isScrollAtBottom;
return function (deltaY) {
var smoothOffset = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : false;
var originScroll =
// Pass origin wheel when on the top
deltaY < 0 && scrollPingRef.current.top ||
// Pass origin wheel when on the bottom
deltaY > 0 && scrollPingRef.current.bottom;
if (smoothOffset && originScroll) {
// No need lock anymore when it's smooth offset from touchMove interval
clearTimeout(lockTimeoutRef.current);
lockRef.current = false;
} else if (!originScroll || lockRef.current) {
lockScroll();
}
return !lockRef.current && originScroll;
};
});