React-Navigation：不变违反：元素类型无效：预期为字符串，但未定义

Question

使用React-Navigation的StackNavigator时出现错误。

下面我向您展示我的代码，我拥有的版本以及package.json的所有配置

这是代码：

import {React} from 'react'
import { StackNavigator } from 'react-navigation';
import LoginForm from '../view/screen/LoginForm'
import Setting from '../view/screen/Setting'

export const AppNavigator = StackNavigator({
  Login: { screen: LoginForm },
  Setting: { screen: Setting }
});

这是我的配置：

 1. react-navigation@1.5.13 
 2. npm version: 5.6.0
 3. react-native-cli: 2.0.1
 4. react-native: 0.57.5

这是我的package.json

  "dependencies": {
    "firebase": "^5.5.9",
    "react": "16.6.1",
    "react-native": "0.57.5",
    "react-native-elements": "^0.19.1",
    "react-native-navigation": "^2.2.0",
    "react-native-ui-lib": "^3.6.1",
    "react-navigation": "^1.0.0-beta.22",
    "react-redux": "^5.1.1",
    "redux": "^4.0.1",
    "redux-thunk": "^2.3.0"
  }

该错误显示在屏幕截图中

App.js是。 21行是带有提供程序组件的行。 看：没有添加StackNavigator，我没有错误。

import AppNavigator from "./routers/Router"

    render(){
        return (
            <Provider store={createStore(reducers, {}, applyMiddleware(ReduxThunk))}>
                <AppNavigator />
            </Provider>
        )
    }
}



export default App;

Answer 1

解决方案是使用export const在AppsNavigator中更改export default。

export default AppNavigator = StackNavigator({
  Login: { screen: LoginForm },
  Setting: { screen: Setting }
});