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I am running a function that downloads the data from the server and runs it after an interval with the help of setInterval. The issue is that I am unable to change the state of the component inside the setInterval(inside the function I have defined). I need this state to be changed because Child component needs to re-render a few things whenever downloads happen.

Here is the similar code (just for demo purpose) which demonstrate the problem I am facing.

import React, { useState, useEffect, useRef, useReducer } from 'react';
import './App.css';
import Child from './Child';

const App = () => {
  const [reset, setReset] = useState(false);

  const changeState = () => {
    console.log('changing state from', reset);
    setReset(!reset);
    console.log('changing state to', reset);
  };

  const init = () => {
    setInterval(changeState, 1000);
  };

  return (
    <>
      <button onClick={init}>Start</button>
      <button onClick={changeState}>Change</button>
      <Child reset={reset} />
    </>
  );
};

export default App;

  1. When you click the Change button state of the button changes perfectly.
  2. but if you click start button (click it once), it will start calling the setReset to change the state but it has no impact. This is how the output looks like in this case.

enter image description here

Child component

import React, { useState, useEffect, useRef, useReducer } from 'react';


const Child = (props) => {
    
    return (
      <>
       {props.reset ? "hello" : "tello"}
      </>
    );
};


export default Child;

You can edit the code here https://stackblitz.com/edit/react-aj5wdf?devtoolsheight=33&file=src/App.js

Note: I have beginner-level experience with React.

Thanks.

Suleman
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0 Answers0