signal-desktop/ts/components/ContactPills.tsx
2021-09-17 18:24:21 -04:00

38 lines
899 B
TypeScript

// Copyright 2021 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
import React, {
useRef,
useEffect,
Children,
FunctionComponent,
ReactNode,
} from 'react';
import { usePrevious } from '../hooks/usePrevious';
import { scrollToBottom } from '../util/scrollToBottom';
type PropsType = {
children?: ReactNode;
};
export const ContactPills: FunctionComponent<PropsType> = ({ children }) => {
const elRef = useRef<null | HTMLDivElement>(null);
const childCount = Children.count(children);
const previousChildCount = usePrevious(0, childCount);
useEffect(() => {
const hasAddedNewChild = childCount > previousChildCount;
const el = elRef.current;
if (hasAddedNewChild && el) {
scrollToBottom(el);
}
}, [childCount, previousChildCount]);
return (
<div className="module-ContactPills" ref={elRef}>
{children}
</div>
);
};