useDidMount
March 13, 2023 ยท View on GitHub
A hook that takes in a function to execute when the component has finished mounting.
Why? ๐ก
- takes care of performing a callback when the component mounts
- Is intended as a shortcut to
useEffect(onMount, [])
Basic Usage:
import { useState } from 'react';
import { Typography } from 'antd';
import useDidMount from 'beautiful-react-hooks/useDidMount';
const ComponentDidMount = () => {
const [mounted, setIsMounted] = useState(false);
useDidMount(() => {
const timeout = setTimeout(() => {
setIsMounted(true);
clearTimeout(timeout);
}, 1000);
});
return (
<DisplayDemo title="useDidMount">
{mounted && (<Typography.Paragraph>Component did mount!</Typography.Paragraph>)}
</DisplayDemo>
);
};
<ComponentDidMount />
Callback setter syntax:
if the first parameter is not provided, the returned function (a callback setter) can be used to set the useDidMount handler, as long as
it is immediately invoked.
Please note: the returned callback setter is meant to change the value of the callback reference only, it does not cause the component rerender nor should not be invoked asynchronously.
import { useState } from 'react';
import { Typography } from 'antd';
import useDidMount from 'beautiful-react-hooks/useDidMount';
const ComponentDidMount = () => {
const [mounted, setIsMounted] = useState(false);
const onMount = useDidMount();
onMount(() => {
const timeout = setTimeout(() => {
setIsMounted(true);
clearTimeout(timeout);
}, 1000);
});
return (
<DisplayDemo title="useDidMount">
{mounted && (<Typography.Paragraph>Component did mount!</Typography.Paragraph>)}
</DisplayDemo>
);
};
<ComponentDidMount />
โ Pro tip:
When using a React function component you should not really think of it in terms of "lifecycle".
The useDidMount hook is indeed intended as a shortcut to useEffect(onMount, []).
To deep understanding useEffect, what it is and how it should be properly used, please read
"A complete guide to useEffect"
by Dan Abramov
Mastering the hook
โ When to use
- When in need of performing a function after the component mounts
๐ When not to use
- You can't use it asynchronously since this will break the rules of hooks
- If using the callback setter, it should not be used asynchronously but immediately invoked
Types
import { type GenericFunction, type Noop } from './shared/types';
/**
* Returns a callback setter for a function to be performed when the component did mount.
*/
declare const useDidMount: <TCallback extends GenericFunction = Noop>(callback?: TCallback | undefined) => import("./shared/types").CallbackSetter<undefined>;
export default useDidMount;