Question

我正在研究React-Native项目，并在尝试实施反应导航时遇到问题。我按照教程进行操作，在尝试运行项目时，我收到一条错误消息：

Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: object. You likely forgot to export your component from the file it’s defined in.

我在网上搜索过，包括这个网站，但无法找到任何解决方案。这是我的代码： index.js：

import React, { Component } from 'react';
import { Stack } from './config/Router';

class Application extends Component{
  render(){
    <View>
      return <Stack />;
    </View>
  }
}

export default Application;

这是路由器：

import React from 'react';
import { StackNavigator } from 'react-navigation';

import Login from '../components/Login';
import Home from '../components/Home';

export const Stack = StackNavigator({
  Login:{
    screen: Login
  },
  Home:{
    screen: Home,
    navigationOptions: {
      title: 'Home'
    }
  }
});

这是index.ios.js：

import { AppRegistry } from 'react-native';
import Application from './index'

AppRegistry.registerComponent('Application', () => Application);

如何修复错误？提前谢谢！

Answer 1

看起来像是

class Application extends Component{
  render(){
    <View>
      return <Stack />;
    </View>
  }
}

应该是

class Application extends Component{
  render(){
    return(
      <View>
        <Stack />
      </View>
    );
  }
}

此外，您还需要在index.js中导入View组件

You likely forgot to export your component from the file it’s defined in.

这几乎总是导致无效元素错误的原因，因此请务必仔细检查导入。

元素类型无效：期望得到一个字符串/类/函数：object

1 个答案: