在Gatsby中反应挂钩:无效的挂钩调用 [英] React hooks in Gatsby: Invalid hook call

问题描述

尝试从React示例中实现自定义钩子: https://reactjs.org/docs/hooks-faq.html#how-to-get-the-previous-props-or-state ，但出现以下错误:

Trying to implement a custom hook from a react example: https://reactjs.org/docs/hooks-faq.html#how-to-get-the-previous-props-or-state, but I get the following error:

错误:

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

当我尝试将其作为自定义钩子usePrevious导入时，在useEffect上发生了错误.

The error happen on useEffect when I try to import it as a custom hook usePrevious.

我尝试了以下操作: 验证react-dom和react在同一版本上 react-dom@16.8.5 react@16.8.5

I tried following: verified that react-dom and react is on the same version react-dom@16.8.5 react@16.8.5

已验证我只有一个版本的React

Verfied I only have one version of React

我也相信代码没有违反任何钩子规则.

Also I do belive the code is not breaking any rules of hooks.

也尝试在stackoverflow上查看相关问题.

Also tried looking at related issues here on stackoverflow.

代码:

// file: use-previous.js

import { useRef, useEffect} from "React"

export const usePrevious = (value) =>  {

    const ref = useRef();
    useEffect(() => {
      ref.current = value;
    });




    return ref.current;
}

// file: layout.js

import React, { useState, useEffect } from "react"

import Header from "./header/header"

import { useFacetsData } from "../hooks/use-facets-data"
import { usePrevious } from "../hooks/use-previous"


export default ({ children, ...props }) => {

    const [ searchValue, setSearchValue ] = useState("")

    const [ facetsSelected, setFacetsSelected ] = useState([])

    const facets = useFacetsData()


    const oldSearchValue = usePrevious(searchValue)
    // const oldFacetsSelected = usePrevious(facetsSelected)

    useEffect(() => {
        // if new searchvalue or new facetvalue

        // if (searchValue !== oldSearchValue || facetsSelected !== oldFacetsSelected) makeSearch()
    }) 

    function makeSearch() {
        console.log('make search')

        // move to searchpage 
    }

    function handleSearchChange(search) {
        setSearchValue(search)
    }

    function handleFacetChange(facets) {
        setFacetsSelected(facets)
    }   

    return   (
        <div>
            {/* Main sticky header */}
            <Header 
                facets={ facets } 
                onSearchChange={ handleSearchChange } 
                onFacetChange={ handleFacetChange } >
            </Header>

            {/* route content */}
           {React.cloneElement(children, { facets })}
        </div>
    )
}

推荐答案

您在usePrevious hooks文件中的导入不正确. useRef和useEffect应该从'react'而不是React导入；

Your import in usePrevious hooks file is incorrect. useRef and useEffect should be import from 'react' and not React;

import { useRef, useEffect} from "react"

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