I am trying to create a simple stopwatch app and getting the following error. I have tried the solutions for similar question yet have been unable to identify the real cause and solve it
here's my code
import React, { useState, useEffect } from "react"
function Watch() {
const [iter, setiter] = useState(0);
const [running, setRunning] = useState(false);
const [time, setTime] = useState("0:0:0");
const [start, setStart] = useState([]);
const [today, setToday] = useState([]);
useEffect(() => {
let interval;
if (iter == 0) {
var today = new Date()
setStart([today.getHours(), today.getMinutes(), today.getSeconds()])
}
if (running) {
interval = setInterval(() => {
setiter((previter) => previter + 10);
}, 10);
} else if (!running) {
clearInterval(interval);
}
var t = new Date()
setToday([t.getHours(), t.getMinutes(), t.getSeconds()])
return () => clearInterval(interval);
}, [running]);
return (
<div className="stopwatch">
<div className="numbers">
{setTime(running ? (String(today[0] - start[0]) + ':' + String(today[1] - start[1]) + ':' + String(today[2] - start[2])) : time)}
<span>{time}</span>
</div>
<div className="buttons">
<button onClick={() => setRunning(true)}>Start</button>
<button onClick={() => setRunning(false)}>Stop</button>
<button onClick={() => setTime("0:0:0")}>Reset</button>
</div>
</div>
);
};
export default Watch
Please note I am beginner at Next.js this is one of my first project.
Please consider this part again. The error comes from the below line:
<div className="numbers">
{setTime(running ? (String(today[0] - start[0]) + ':' + String(today[1] - start[1]) + ':' + String(today[2] - start[2])) : time)}
<span>{time}</span>
</div>
Please set time while component mounting using useEffect hook rather than now.
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