setInterval 使用 nextjs 和钩子

Question

I' m traying to implement a loading using nextjs and hooks. I have to do a fetch to check new info every 3 minutes and when thats appends I want to use a loading. I create a setLoading and it starts at false and inside a setIntervar pass to true, but I dont 'know why dosen 't work.. why? Thanks!

here is my code:

import React, { useState, useEffect } from "react";
import Context from "../../config/Context";
import { checkNewData } from "../../helper/index";

function Home() {

  const [contentLoading, setLoading] = useState(false);
  const data = context.events[0];

  useEffect(() => {
    setInterval(() => {
      if (data.live == false) {
        setLoading(true);
        checkNewData();
      }
      setLoading(false)
    }, 10000);

  return (
    <React.Fragment>
      {contentLoading ? <p>loading</p> : <p>no loading</p>
    </React.Fragment>
  );
}

export default Home;

Answer 1

Ok, so here You have working interval

(Every 3 sec calling api, and counts how many times it works(not needed just FYI)

In the function responsible for Api call you should turn on the loader - then every 3 seconds the data is called again

---

const Home = (props) => {

        const [loading, setLoading] = useState(false);
        const [check, setCheck] = useState(0)

        const callApi = () => {
            Here you should call your api + set loader
            if fetching(setLoading(true))
            if fetched(setLoading(false))
        }

        useEffect(() => {
            const id = setInterval(() => {
                callApi()
                setCheck(check + 1)
            }, 3000);
            return () => clearInterval(id);
        }, [check])

        return (
            <React.Fragment>
                {loading ? <p>Loading</p> : <p>No Loading</p>}
                <p>Times check execute {check}</p>
            </React.Fragment>
        );
    }

Answer 2

A better way to do this now will be to use a plugin like SWR . It will handle the data fetch and even the loading state seamlessly. Check the documentation here: https://swr.vercel.app