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@gragland
Last active Nov 30, 2022
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React Hook recipe from https://usehooks.com
import React, { useState, useEffect, useCallback } from 'react';
// Usage
function App() {
const { execute, status, value, error } = useAsync(myFunction, false);
return (
<div>
{status === 'idle' && <div>Start your journey by clicking a button</div>}
{status === 'success' && <div>{value}</div>}
{status === 'error' && <div>{error}</div>}
<button onClick={execute} disabled={status === 'pending'}>
{status !== 'pending' ? 'Click me' : 'Loading...'}
</button>
</div>
);
}
// An async function for testing our hook.
// Will be successful 50% of the time.
const myFunction = () => {
return new Promise((resolve, reject) => {
setTimeout(() => {
const rnd = Math.random() * 10;
rnd <= 5
? resolve('Submitted successfully 🙌')
: reject('Oh no there was an error 😞');
}, 2000);
});
};
// Hook
const useAsync = (asyncFunction, immediate = true) => {
const [status, setStatus] = useState('idle');
const [value, setValue] = useState(null);
const [error, setError] = useState(null);
// The execute function wraps asyncFunction and
// handles setting state for pending, value, and error.
// useCallback ensures the below useEffect is not called
// on every render, but only if asyncFunction changes.
const execute = useCallback(() => {
setStatus('pending');
setValue(null);
setError(null);
return asyncFunction()
.then(response => {
setValue(response);
setStatus('success');
})
.catch(error => {
setError(error);
setStatus('error');
});
}, [asyncFunction]);
// Call execute if we want to fire it right away.
// Otherwise execute can be called later, such as
// in an onClick handler.
useEffect(() => {
if (immediate) {
execute();
}
}, [execute, immediate]);
return { execute, status, value, error };
};
@TusharShahi
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TusharShahi commented Jun 25, 2022

Is it ideal to use a function as a useCallback dependency? Function is created fresh in every render (unless handled).

@tamiradler
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tamiradler commented Nov 30, 2022

The init value of state should be depend on immediate variable:
const [status, setStatus] = useState(() => immediate ? 'pending' : 'idle' );

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