开发者问题收集

React-router 显示无效的钩子调用

2021-11-19
6420

我的 React 应用中发生了 invalid hook 错误,该错误是由 react-router 引起的,但我似乎无法检测出它来自何处。完整错误如下:

Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:
1. You might have mismatching versions of React and the renderer (such as React DOM)
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app
See https://reactjs.org/link/invalid-hook-call for tips about how to debug and fix this problem.

我的 React 版本没有不匹配,错误也不是由上述任何原因引起的(不能肯定地说,但我确实没有)。我遵循了 此处 的 react-router 文档。我知道我搞砸了一些东西,但我不知道在哪里。

以下是必要的组件,从入口文件开始。

index.js

import React from "react";
import ReactDOM from "react-dom";
import { BrowserRouter } from "react-router-dom";
import {
  ApolloProvider,
  ApolloClient,
  createHttpLink,
  InMemoryCache,
} from "@apollo/client";
import { setContext } from "@apollo/client/link/context";
import {AUTH_TOKEN} from "./constants";
import App from "./components/App";
import "./styles/index.css";

const httpLink = createHttpLink({ uri: "http://localhost:4000" });

const authLink = setContext((_, { headers }) => {
  const token = localStorage.getItem(AUTH_TOKEN);

  return {
    ...headers,
    authorization: token ? `Bearer ${token}` : "",
  };
});

/*Instantiates Apollo client and connect to GraphQL server.
This will take the server link and an instantiation of the cache funtionality*/
const client = new ApolloClient({
  link: authLink.concat(httpLink),
  cache: new InMemoryCache(),
});

ReactDOM.render(
  <BrowserRouter>
    <ApolloProvider client={client}>
      <React.StrictMode>
        <App />
      </React.StrictMode>
    </ApolloProvider>
  </BrowserRouter>,
  document.getElementById("root")
);

App.js

import React from "react";
import LinkList from "./LinkList";
import CreateLink from "./CreateLink";
import Header from "./Header";
import Login from './Login';
import { Routes, Route } from "react-router-dom";
import "../styles/App.css";

function App() {
  return (
    <div className="center w85">
      <Header />
      <div className="ph3 pv1 background-gray">
        <Routes>
          <Route path="/" element={<LinkList/>} />
          <Route path="/create" element={<CreateLink/>} />
          <Route path="/login" element={<Login/>} />
        </Routes>
      </div>
    </div>
  );
}

export default App;

Header.js

import React from "react";
import { useNavigate, Link } from "react-router-dom";
import { AUTH_TOKEN } from "../constants";

export default function Header() {
    const history = useNavigate();
    const authToken = localStorage.getItem(AUTH_TOKEN);

    return (
        <div className="flex pa1 justify-between nowrap orange">
            <div className="flex flex-fixed black">
                <div className="fw7 mr1">Hacker News</div>
                <Link to="/" className="ml1 no-underline black">
                    new
                </Link>
                <div className="ml1">|</div>
                <Link to="/top" className="ml1 no-underline black">
                    top
                </Link>
                <div className="ml1">|</div>
                <Link to="/search" className="ml1 no-underline black">
                    search
                </Link>
                {authToken && (
                    <div className="flex">
                        <div className="ml1">|</div>
                        <Link to="/create" className="ml1 no-underline black">
                            submit
                        </Link>
                    </div>
                )}
            </div>
            <div className="flex flex-fixed">
                {authToken ? (
                    <div
                        className="ml1 pointer black"
                        onClick={() => {
                            localStorage.removeItem(AUTH_TOKEN);
                            history.push(`/`);
                        }}
                    >
                        logout
                    </div>
                ) : (
                    <Link to="/login" className="ml1 no-underline black">
                        login
                    </Link>
                )}
            </div>
        </div>
    );
}

LinkList.js

import React from "react";
import { useQuery, gql } from "@apollo/client";
import Link from "./Link";

const LinkList = () => {

  const FEED_QUERY = gql`
    {
      feed {
        id
        links {
          id
          createdAt
          url
          description
        }
      }
    }
  `;

  const { loading, error, data } = useQuery(FEED_QUERY);

  if (loading) return <p style={{padding: 20, textAlign:"center"}}>Loading...</p>;

  if (error) console.log(error);

  return (
    <div>
      {data &&
        data.feed.links.map((link) => <Link key={link.id} link={link} />)}
    </div>
  );
};

export default LinkList;

CreateLink.js

import React, { useState } from "react";
import { useMutation, gql } from "@apollo/client";
import { useNavigate } from "react-router-dom";

export default function CreateLink() {
    const [formState, setFormState] = useState({ description: "", url: "" });

    const history = useNavigate();

    const CREATE_LINK_MUTATION = gql`
        mutation PostMutation($url: String!, $description: String!) {
            post(url: $url, description: $description) {
                id
                createdAt
                url
                description
            }
        }
    `;

    const [createLink] = useMutation(CREATE_LINK_MUTATION, {
        variables: {
            description: formState.description,
            url: formState.url,
        },
        onCompleted: () => history.push("/")
    });

    return (
        <div>
            <form
                onSubmit={(e) => {
                    e.preventDefault();
                    createLink();
                }}
            >
                <div className="flex flex-column mt3">
                    <input
                        type="text"
                        className="mt2"
                        placeholder="A description for the link"
                        onChange={(e) =>
                            setFormState({
                                ...formState,
                                description: e.target.value,
                            })
                        }
                        value={formState.description}
                    />
                    <input
                        className="mb2"
                        value={formState.url}
                        onChange={(e) =>
                            setFormState({
                                ...formState,
                                url: e.target.value,
                            })
                        }
                        type="text"
                        placeholder="The URL for the link"
                    />
                </div>
                <button type="submit">Submit</button>
            </form>
        </div>
    );
}

Login.js

import React, { useState } from "react";
import { useNavigate } from "react-router-dom";
import { gql, useMutation } from "@apollo/client";
import { AUTH_TOKEN } from '../constants';

export default function Login() {
    let history = useNavigate();

    const [formState, setFormState] = useState({
        login: true,
        email: "",
        password: "",
        name: "",
    });

    const SIGNUP_MUTATION = gql`
        mutation SignupMutation(
            $email: string
            $password: string
            $name: string
        ) {
            signup(email: $email, password: $password, name: $name) {
                token
                user {
                    name
                    email
                }
            }
        }
    `;

    const [signup] = useMutation(SIGNUP_MUTATION, {
        variables: {
            email: formState.email,
            password: formState.password,
            name: formState.password,
        },
        onCompleted: ({ signup }) => {
            localStorage.setItem(AUTH_TOKEN, signup.token);
            history.push("/create");
        },
    });

    const LOGIN_MUTATION = gql`
        mutation LoginMutation($email: string, $password: string) {
            login(email: $email, password: $password) {
                token
            }
        }
    `;

    const [login] = useMutation(LOGIN_MUTATION, {
        variables: {
            email: formState.email,
            password: formState.password,
        },
        onCompleted: ({ login }) => {
            localStorage.setItem(AUTH_TOKEN, signup.token);
            history.push("/");
        },
    });

    return (
        <div>
            <h4 className="mv3">{formState.login ? "Login" : "Sign Up"}</h4>
            <div className="flex flex-column">
                {!formState.login && (
                    <input
                        value={formState.name}
                        onChange={(e) =>
                            setFormState({
                                ...formState,
                                name: e.target.value,
                            })
                        }
                        type="text"
                        placeholder="Your name"
                    />
                )}
                <input
                    value={formState.email}
                    onChange={(e) =>
                        setFormState({
                            ...formState,
                            email: e.target.value,
                        })
                    }
                    type="text"
                    placeholder="Your email address"
                />
                <input
                    value={formState.password}
                    onChange={(e) =>
                        setFormState({
                            ...formState,
                            password: e.target.value,
                        })
                    }
                    type="password"
                    placeholder="Choose a safe password"
                />
            </div>
            <div className="flex mt3">
                <button
                    className="pointer mr2 button"
                    onClick={() => (formState.login ? login : signup)}
                >
                    {formState.login ? "login" : "create account"}
                </button>
                <button
                    className="pointer button"
                    onClick={(e) =>
                        setFormState({
                            ...formState,
                            login: !formState.login,
                        })
                    }
                >
                    {formState.login
                        ? "need to create an account?"
                        : "already have an account?"}
                </button>
            </div>
        </div>
    );
}

根据项目中的软件包安装的 React 版本:

[email protected] c:\projects\react-apollo-integration\frontend
+-- @apollo/[email protected]
| `-- [email protected] deduped
+-- @testing-library/[email protected]
| +-- [email protected] deduped
| `-- [email protected] deduped
+-- [email protected]
| `-- [email protected] deduped
+-- [email protected]
| `-- [email protected] deduped
`-- [email protected]
1个回答

我发现我做错了什么。我在项目目录之外安装了 react-router 包。我的错!

Romeo
2021-11-20