20 lines
625 B
TypeScript
20 lines
625 B
TypeScript
import { useState } from '../lib/teact/teact';
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import useLastCallback from './useLastCallback';
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const THRESHOLD = 5;
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export default function useScrolledState(threshold = THRESHOLD) {
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const [isAtBeginning, setIsAtBeginning] = useState(true);
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const [isAtEnd, setIsAtEnd] = useState(true);
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const handleScroll = useLastCallback((e: React.UIEvent<HTMLElement>) => {
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const { scrollHeight, scrollTop, clientHeight } = e.target as HTMLElement;
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setIsAtBeginning(scrollTop < threshold);
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setIsAtEnd(scrollHeight - scrollTop - clientHeight < threshold);
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});
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return { isAtBeginning, isAtEnd, handleScroll };
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}
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