不变冲突试图使帧超出索引NaN的范围

我正在跑步 react-native 聊天应用示例 Even Bacon 跑进 frame out of range NaN 错误:

这里是package.json:

 "firebase": "^5.8.0",
    "react": "16.6.3",
    "react-native": "0.57.8",
    "react-native-elements": "^0.19.1",
    "react-native-gesture-handler": "^1.0.15",
    "react-native-gifted-chat": "^0.7.0",
    "react-navigation": "^3.0.9"

有一些关于不同情况下的错误的在线文章。错误指向 GiftedChat 在Chat.js。我也不知道是什么导致了这个错误。

import React, { Component} from 'react';
import {View, StyleSheet } from 'react-native';
import { GiftedChat } from 'react-native-gifted-chat';
import Fire from '../Fire';

class Chat extends React.Component {
    static navigationOptions = ({ navigation}) => ({
        title: (navigation.state.params || {}).name || 'Chat!',
    });

    state = {
        messages: {},
    };

    componentDidMount() {
        Fire.shared.on(message =>
              this.setState(previousState => ({
                messages: GiftedChat.append(previousState.messages, message),
              }))
        );
    }

    componentWillUnmount() {
      Fire.shared.off();
    }

    get user() {
      // return our name and our UID for GiftedChat to parse
      return {
          name: this.props.navigation.state.params.name,
          _id: Fire.shared.uid,
      };
    }

    render() {
        return (
            <GiftedChat   <<<<==this is line:37
              messages={this.state.messages}
              onSend={Fire.shared.send}
              user={this.user}
            /> 
        );
    }
}

const styles = StyleSheet.create({});



export default Chat;