问如何使用钩子在react native中保存/下载生成二维码？

EN

import React, { useState } from 'react';
import { StyleSheet, View, Text, TextInput, TouchableOpacity, AsyncStorage } from 'react-native';
import QRCode from 'react-native-qrcode-generator';

export default function App() {
  const [key, setKey] = useState(null);
  const [value, setValue] = useState(null);
  const [downloadKey, setDownloadKey] = useState(null);
  const [qrCodeValue, setQRCodeValue] = useState('');

  const save = async () => {
    //You have to implement the function that saves your information into your database.
    //Here I'm saving data to AsyncStorage. (For sample)

    await AsyncStorage.setItem(key, value);
  }

  const download = async () => {
    //You have to implement the function that retrieves your information from your database for given key.
    //Here I'm retrieving data from AsyncStorage. (For sample)

    const qrValue = await AsyncStorage.getItem(downloadKey);
    setQRCodeValue(qrValue);
  }

  return (
    <View style={styles.container}>

      <View style={styles.row}>
        <TextInput placeholder={'Key'} value={key} onChangeText={(key) => setKey(key)} style={styles.textInput}/>
        <TextInput placeholder={'Value'} value={value} onChangeText={(value) => setValue(value)} style={styles.textInput}/>
      </View>
      <TouchableOpacity style={{ flexDirection: 'row', marginBottom: 50 }} onPress={save}>
        <Text style={styles.button}>Save</Text>
      </TouchableOpacity>

      {qrCodeValue ? <QRCode value={qrCodeValue} size={200} /> : null}

      <Text style={{ margin: 10 }}>{qrCodeValue}</Text>

      <View style={[styles.row, { marginTop: 50 }]}>
        <TextInput placeholder={'Key'} value={downloadKey} onChangeText={(downloadKey) => setDownloadKey(downloadKey)} style={styles.textInput}/>
        <TouchableOpacity style={{ flex: 1, flexDirection: 'row' }} onPress={download}>
          <Text style={styles.button}>Download</Text>
        </TouchableOpacity>
      </View>

    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#fff',
    alignItems: 'center',
    paddingTop: 50,
    paddingBottom: 50
  },
  row: {
    flexDirection: 'row',
  },
  textInput: {
    flex: 1,
    borderColor: '#808080',
    borderWidth: 1,
    borderRadius: 5,
    margin: 5,
    paddingLeft: 5,
    paddingRight: 5,
  },
  button: {
    flex: 1,
    borderColor: '#0040FF',
    backgroundColor: '#0080FF',
    borderWidth: 1,
    borderRadius: 5,
    margin: 5,
    textAlign: 'center',
    textAlignVertical: 'center',
    height: 30
  },
});

import RNQRGenerator from 'rn-qr-generator';
 
RNQRGenerator.generate({
  value: 'string_value',
  height: 100,
  width: 100,
  base64: false,
  backgroundColor: 'black',
  color: 'white',
})
  .then(response => {
    const { uri, width, height, base64 } = response;
  })
  .catch(error => console.log('Error creating QR code image', error));