An unknown bug doesn't allow the quotes app to work. What's the issue?

Atman Atos · Apr 23, 2023

The current error that I am getting is caught TypeError: Cannot read properties of null (reading 'useEffect') I tried adding React to the start of every useEffect and useState method but it doesn't fix it. I've tried different scenarios but the issue persists. Any help with why this code isn't working?

HTML:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>React quote maker</title>
    <script crossorigin src="https://unpkg.com/react@18/umd/react.production.min.js"></script>
    <script crossorigin src="https://unpkg.com/react-dom@18/umd/react-dom.production.min.js"></script>
    <link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC" crossorigin="anonymous">
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/[email protected]/font/bootstrap-icons.css">
    <link rel="shortcut icon" href="quote logo.png" type="image/x-icon">
</head>
<body>
    <script src="https://unpkg.com/@babel/standalone/babel.min.js"></script>
    <div id="root"></div>
  <script type="text/babel">
    const { useEffect, useState } = React;
    import { createRoot } from 'react-dom';
    
    let quotesArr;
   useEffect(() => {
    fetch("https://type.fit/api/quotes")
      .then(res => res.json())
      .then(data => {
        quotesArr = data
        console.log("quotesArr")
        console.log(quotesArr)
        RandomQuotVal()
        RandomAuthVal()
        getRandomColor()
        Myapp()
      })
   }, [])

  const RandomQuotVal = () => {
    return (
      <>
        {quotesArr[Math.floor(Math.random() * quotesArr.length)].text}
      </>
    )
  }

  const RandomAuthVal = () => {
    return (
      <>
        {quotesArr[Math.floor(Math.random() * quotesArr.length)].author}
      </>
    )
  }

  const getRandomColor = () => {
    const letters = "0123456789ABCDEF";
    let color = "#";
    for (let i = 0; i < 6; i++) {
      color += letters[Math.floor(Math.random() * 16)];
    }
    return (
      color
    );
  };



  const Myapp = ({quotesArr}) => {
    const [quote, setQuote] = useState(quotesArr[0].text);
    const [author, setAuthor] = useState(quotesArr[0].author);

    useEffect(() => {
      const bgColor = getRandomColor();
      document.getElementById("main").style.backgroundColor = bgColor;
      document.getElementById("text").style.color = bgColor;
      document.getElementById("author").style.color = bgColor;
    }, [])

    const handleClick = () => {
      const randomIndex = Math.floor(Math.random() * quotesArr.length);
      setQuote(quotesArr[randomIndex].text);
      setAuthor(quotesArr[randomIndex].author);
      const bgColor = getRandomColor();
      document.getElementById("main").style.backgroundColor = bgColor;
      document.getElementById("text").style.color = bgColor;
      document.getElementById("author").style.color = bgColor;
    }

    return (
      <main id="main"  style={{height: "100vh", width: "100vw"}}>
        <div id="quote-box" style={{minHeight: "40vh", height: "fit-content" }} className="container-lg col-lg-6 col-md-6 col-sm-12 col-xs-6 d-flex justify-content-center align-items-center">
          <section className="bg-white text-center rounded p-5 mt-5" style={{width: "100%", height: "auto", boxSizing: "border-box"} }>
            <div id="text" className="fw-bold fs-2">
              "{text}.
            </div>
            <span id="author" className="d-block text-end lead">
              -{author}
            </span>
            <div className="d-flex justify-content-between align-items-center mt-5" >
              <div className="fs-1">
                <a href={`https://twitter.com/intent/tweet?text=${encodeURIComponent(`"${text}" - ${author}`)}`} target="_blank" rel="noopener noreferrer" id="tweet-quote" className="text-decoration-none"><i className="bi bi-twitter"></i></a>
              </div>
              <button type="button" className="btn btn-success align-middle" id="new-quote" onClick={handleClick}>New Quote</button>
            </div>
          </section>
        </div>
        <div className="d-flex justify-content-center mt-5">quotes app</div>
      </main>
      
    )
  }
        const domContainer = document.querySelector('#root');
        const myRoot = ReactDOM.createRoot(domContainer)
        myRoot.render(<Myapp />);
    </script>
    
</body>
</html>

Phro0244 · Apr 23, 2023

It seems like the issue is with importing the useEffect and useState hooks from the React package. You should not import those hooks separately, but rather import the entire React package and access the hooks through it.

Instead of: const { useEffect, useState } = React;
You should use: import React, { useEffect, useState } from 'react';
So the corrected import statement would look like this:

import React, { useEffect, useState } from 'react';
import { createRoot } from 'react-dom';

Also, it seems like you are passing quotesArr as a prop to Myapp, but it is not needed as it is already declared globally. You can remove it from the Myapp component declaration:
const Myapp = () => { ... }

These changes should fix the issue you are facing.

Atman Atos · Apr 24, 2023

Phro0244 said:
It seems like the issue is with importing the useEffect and useState hooks from the React package. You should not import those hooks separately, but rather import the entire React package and access the hooks through it.

Instead of: const { useEffect, useState } = React;
You should use: import React, { useEffect, useState } from 'react';
So the corrected import statement would look like this:

import React, { useEffect, useState } from 'react';
import { createRoot } from 'react-dom';

Also, it seems like you are passing quotesArr as a prop to Myapp, but it is not needed as it is already declared globally. You can remove it from the Myapp component declaration:
const Myapp = () => { ... }

These changes should fix the issue you are facing.

Using
import React, { useEffect, useState } from 'react';
import { createRoot } from 'react-dom';
gives an error
caught ReferenceError: require is not defined

Phro0244 · May 7, 2023

It seems like the issue is with importing the useEffect and useState hooks from the React package. You should not import those hooks separately, but rather import the entire React package and access the hooks through it.

Instead of:
const { useEffect, useState } = React;

You should use:

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

So the corrected import statement would look like this:

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

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An unknown bug doesn't allow the quotes app to work. What's the issue?

Atman Atos

Phro0244

Atman Atos

Phro0244

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