Files
flxn-app/src/components/infinite-scroll.tsx
T
2026-07-13 23:57:31 -07:00

74 lines
1.8 KiB
TypeScript

import { ReactNode, useEffect, useRef, useState } from "react";
import { Box } from "@mantine/core";
interface InfiniteScrollProps<T> {
items: T[];
renderItem: (item: T, index: number) => ReactNode;
batchSize?: number;
initialCount?: number;
rootMargin?: string;
loader?: ReactNode;
hasMore?: boolean;
loading?: boolean;
onLoadMore?: () => void;
}
const InfiniteScroll = <T,>({
items,
renderItem,
batchSize = 25,
initialCount = batchSize,
rootMargin = "600px 0px",
loader,
hasMore = false,
loading = false,
onLoadMore,
}: InfiniteScrollProps<T>) => {
const [visibleCount, setVisibleCount] = useState(initialCount);
const [prevItems, setPrevItems] = useState(items);
const sentinelRef = useRef<HTMLDivElement>(null);
if (prevItems !== items) {
setPrevItems(items);
setVisibleCount(initialCount);
}
const hasHiddenItems = visibleCount < items.length;
const showLoader = hasHiddenItems || hasMore || loading;
useEffect(() => {
const sentinel = sentinelRef.current;
if (!sentinel) return;
const observer = new IntersectionObserver(
(entries) => {
if (!entries.some((entry) => entry.isIntersecting)) return;
if (visibleCount < items.length) {
setVisibleCount((count) => Math.min(count + batchSize, items.length));
} else if (hasMore && !loading) {
onLoadMore?.();
}
},
{ rootMargin }
);
observer.observe(sentinel);
return () => observer.disconnect();
}, [items, visibleCount, batchSize, hasMore, loading, onLoadMore, rootMargin]);
return (
<>
{items.slice(0, visibleCount).map((item, index) => renderItem(item, index))}
{showLoader && (
<>
<Box ref={sentinelRef} />
{loader}
</>
)}
</>
);
};
export default InfiniteScroll;