如何在TextInput中添加fix符号，当用户输入某些内容时保持静态(React Native)

import React, { useState } from 'react';
import { TextInput, View, Text, StyleSheet } from 'react-native';

const App = () => {
  const [inputValue, setInputValue] = useState('');

  return (
    <View style={styles.container}>
      <TextInput
        style={styles.input}
        value={inputValue}
        onChangeText={text => setInputValue(text)}
        placeholder="请输入内容"
      />
      {inputValue !== '' && <Text style={styles.fixSymbol}>fix</Text>}
    </View>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
  input: {
    width: 200,
    height: 40,
    borderWidth: 1,
    borderColor: 'gray',
    marginBottom: 10,
    paddingHorizontal: 10,
  },
  fixSymbol: {
    position: 'absolute',
    top: 12,
    right: 10,
    fontSize: 16,
    color: 'gray',
  },
});

export default App;