screens/CalendarScreen.js

import React, {useRef, useState, useEffect} from 'react';
import {Animated, Button, StyleSheet, View} from 'react-native';

function FadeInAndOut() {
  const animation = useRef(new Animated.Value(1)).current;
  const [hidden, setHidden] = useState(false);
  useEffect(() => {
    Animated.timing(animation, {
      toValue: hidden ? 0 : 1,
      useNativeDriver: true,
    }).start();
  }, [hidden, animation]);

  return (
    <View>
      <Animated.View
        style={[
          styles.rectangle,
          {
            opacity: animation,
          },
        ]}
      />
      <Button
        title="Toggle"
        onPress={() => {
          setHidden(!hidden);
        }}
      />
    </View>
  );
}

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