为什么反应本机会给我有关我的功能的错误？

Question

图像中有错误。 我正在尝试使用右侧菜单制作应用程序。我做了很多尝试，我几乎成功使用了react bootstrap，但实际上没有成功。现在，我尝试使用此弹出菜单，但出现很多错误。幸运的是，我解决了大多数问题，但是我不知道如何解决这一问题。我希望该菜单打开我创建并称为设置的第二个页面（屏幕）。我希望它可以打开网站的链接。有人知道如何解决此错误吗？ 这是我的代码： 主页：

import React from 'react';
import {Text,View,Button,Icon} from 'react-native';
import PopupMenu from './popupmenu';

onPopupEvent = (eventName, index) => {
  if (eventName !== 'itemSelected') return
  if (index === 0) showSettins = () =>{this.props.navigation.navigate('Settings');}
  else showSettins = () =>{this.props.navigation.navigate('Settings');}
}


export default class HomeScreen extends React.Component {




static navigationOptions = {
  title: 'Home',
  headerRight:(
    <PopupMenu actions={['Settings']} onPress={this.onPopupEvent} />
  ),
};



render() {
  const {navigate} = this.props.navigation;
  return (
    <View>
      <Text>Home</Text>
    </View>
  );
 }
}

弹出菜单页面：

import React, { Component} from 'react'
import PropTypes from 'prop-types'
import { View, UIManager, findNodeHandle, TouchableOpacity } from 'react-native'
import Icon from 'react-native-vector-icons/MaterialIcons'

const ICON_SIZE = 24

export default class PopupMenu extends Component {
  static propTypes = {
    // array of strings, will be list items of Menu
    actions:  PropTypes.arrayOf(PropTypes.string).isRequired,
    onPress: PropTypes.func.isRequired
  }

  constructor (props) {
    super(props)
    this.state = {
      icon: null
    }
  }

  onError () {
    console.log('Popup Error')
  }

  onPress = () => {
    if (this.state.icon) {
      UIManager.showPopupMenu(
        findNodeHandle(this.state.icon),
        this.props.actions,
        this.onError,
        this.props.onPress
      )
    }
  }

  render () {
    return (
      <View>
        <TouchableOpacity onPress={this.onPress}>
          <Icon
            name='more-vert'
            size={ICON_SIZE}
            color={'grey'}
            ref={this.onRef} />
        </TouchableOpacity>
      </View>
    )
  }

  onRef = icon => {
    if (!this.state.icon) {
      this.setState({icon})
    }
  }
}