UseEffect挂钩:无法在未安装的组件上执行React状态更新

时间:2020-04-20 05:44:29

标签: javascript reactjs

错误:“ index.js:1警告:无法在已卸载的组件上执行React状态更新。这是无操作,但表示您的应用程序中存在内存泄漏。要修复,取消所有订阅并Home(由Context.Consumer创建)中的useEffect清理功能中的异步任务”


import React, { useState, useEffect } from "react";
import { Link } from "react-router-dom";
import { useMutation } from "@apollo/``react-hooks";
import gql from "graphql-tag";
import { Button, Icon, Label } from "semantic-ui-react";

const LikeButton = ({ user, post: { id, likeCount, likes } }) => {
  const [liked, setLiked] = useState(false);
  useEffect(() => {
    if (user && likes.find(like => like.username === user.username)) {
      setLiked(true);
    } else {
      setLiked(false);
    }
  }, [likes, user]);

  const [likePost] = useMutation(LIKE_POST_MUTATION, {
    variables: { postId: id },
    update(proxy, result) {
      likes = result.data.likePost.likes;
    }
  });

  const likeButton = user ? (
    liked ? (
      <Button color="red">
        <Icon name="heart" />
      </Button>
    ) : (
      <Button basic color="red">
        <Icon name="heart" />
      </Button>
    )
  ) : (
    <Button as={Link} to="/login" basic color="red">
      <Icon name="heart" />
    </Button>
  );
  return (
    <Button as="div" labelPosition="right" onClick={user ? likePost : null}>
      {likeButton}
      <Label basic color="red" pointing="left">
        {likeCount}
      </Label>
    </Button>
  );
};

const LIKE_POST_MUTATION = gql`
  mutation likePost($postId: ID!) {
    likePost(postId: $postId) {
      id
      likeCount
      likes {
        id
        username
      }
    }
  }
`;

export default LikeButton;

当我不喜欢帖子时(例如按钮和计数立即更新),效果很好,但是当我喜欢帖子时,必须刷新页面以更新喜欢计数

0 个答案:

没有答案
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