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import React, { useCallback } from 'react';
import { Poll } from 'which-types';
import PollCard from '../PollCard/PollCard';
interface PropTypes {
polls: Poll[];
mutate: (polls: Poll[], refetch: boolean) => void;
index: number;
style: React.CSSProperties;
key: string;
}
const compareProps = (oldProps: PropTypes, newProps: PropTypes) => {
if (oldProps.key !== newProps.key) return false;
if (oldProps.index !== newProps.index) return false;
if (oldProps.polls !== newProps.polls) return false;
// TODO: uncomment line below to listen to style updates
// if (JSON.stringify(oldProps.style)!== JSON.stringify(newProps.style)) return false;
return true;
};
const RenderItem: React.FC<PropTypes> = React.memo(({
polls, mutate, index, style, key
}) => {
const poll = polls[index];
const setPoll = useCallback((newPoll: Poll) => {
const newPolls = [...polls];
newPolls[index] = newPoll;
// Force-update list-size so everything re-renders
mutate([], false);
mutate(newPolls, false);
}, [mutate, index, polls]);
return (
// To re-render on list resize, add this info to key
<div key={`${key}-${poll._id}-${polls.length}`} style={style}>
<PollCard poll={poll} setPoll={setPoll} />
</div>
);
}, compareProps);
export default RenderItem;
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