运行 React Native App 中的错误：元素类型无效

Question

图片链接： [1]: https://i.stack.imgur.com/8PwUH.jpg [2]: https://i.stack.imgur.com/MiaA6.jpg [3]: https://i.stack.imgur.com/x0Pfx.jpg

错误：元素类型无效：应为字符串（对于内置组件）或 class/function（对于复合组件）但得到：未定义。您可能忘记从定义它的文件中导出您的组件，或者您可能混淆了默认导入和命名导入。检查 App.

的渲染方法

import React, { useState } from "react";
import { NavigationContainer } from "@react-navigation/native";
import { AppLoading } from "expo";

import AppNavigator from "./app/navigation/AppNavigator";
import AuthNavigator from "./app/navigation/AuthNavigator";
import navigationTheme from "./app/navigation/navigationTheme";
import navigationRef from "./app/navigation/rootNavigation";
import OfflineNotice from "./app/components/OfflineNotice";

import AuthContext from "./app/auth/context";
import authStorage from "./app/auth/storage";

export default function App() {
    const [user, setUser] = useState();
    const [isReady, setIsReady] = useState(false);

    const restoreUser = async () => {
        const user = await authStorage.getUser();
        if (user) setUser(user);
    };

    if (!isReady)
        return (
            <AppLoading
                startAsync={restoreUser}
                onFinish={() => setIsReady(true)}
            />
        );

    return (
        <AuthContext.Provider value={{ user, setUser }}>
            <OfflineNotice />
            <NavigationContainer ref={navigationRef} theme={navigationTheme}>
                {user ? <AppNavigator /> : <AuthNavigator />}
            </NavigationContainer>
        </AuthContext.Provider>
    );
}

Answer 1

默认导入不需要括号 {}。此外，您必须从 expo-app-loading 导入 AppLoading，请参阅以下文档：https://docs.expo.io/versions/latest/sdk/app-loading/

解决这个变化

import { AppLoading } from "expo";

至

import AppLoading from 'expo-app-loading'

希望对您有所帮助

运行 React Native App 中的错误：元素类型无效

Error In Running a React Native App : Element type is invalid

reactjs

react-native

react-native-android

expo