reactjs - TypeError: undefined is not an object (evaluating '_firebase.firebase.database')

Question

I am trying out firebase using react native and want to post the data from textbox whenever user hits add. Its giving the error TypeError: undefined is not an object (evaluating '_firebase.firebase.database'). Here is my code.

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


export default function MLManage({navigation}) {

 const [text,setText]=useState('');

 function saveitem(){
    const db=firebase.database().ref("test");
    data.push({
      text : text
    })
    this.setState({text: ""})
  
  }
   
  

    return (
      <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center', marginBottom: 20,padding:20 }}>
        <Text>Machine Learning algo Screen</Text>
        <TextInput
          style={{ width:300, borderColor: 'gray', borderWidth: 1 }}
          onChangeText={(text) => setText(text)}
        />
        <Button title="add"  onPress={()=>{
          saveitem()
        }}/>
      </View>
    );
  }

Answer 1

等待大神答复