@jgierer12/hooks v0.2.5

My personal library of reusable React hooks

Installation

This package is published on both the GitHub Package Registry and the npm registry. To use the GPR, change the registry for the @jgierer12 scope before installing:

echo "@jgierer12:registry=https://npm.pkg.github.com" >> .npmrc

npm install @jgierer12/hooks

import { useMount } from "@jgierer12/hooks";
useMount(...)

// or

import * as hooks from "@jgierer12/hooks";
hooks.useMount(...)

API

Constants

useEventListener

Listen for a specified event and run a callback when it occurs

Kind: global constant

Example

useEventListener(`click`, event => {
  console.log(`Clicked on ${event.target}`);
});

Example

useEventListener(
  `focus`,
  event => {
    console.log(`Input was focused`);
  },
  myInput
);

useMount

Run a callback only on initial mount, but not on rerenders

Kind: global constant

Example

useMount(() => {
  fetchExtraResources();
});

useObjectState

On setState, deep-merge old and new state objects. This resembles React.Component's this.setState, but with deep merging instead of shallow merging

Kind: global constant

Example

const [state, setState] = useObjectState({
  name: {
    first: `Jonas`,
    middle: `Ben`,
    last: `Gierer`,
  },
  age: 4,
});

setState({
  name: {
    middle: ``,
  },
  age: 20,
});

console.log(state);
// {
//    name: {
//      first: `Jonas`,
//      middle: ``,
//      last: `Gierer`,
//    },
//    age: 20,
// }

usePersistentState

useState while persisting the state to localStorage across sessions

Kind: global constant

Example

const [name, setName] = usePersistentState(`name`, `Mike`);
setName(`Jonas`); // `name` will be initialized to `Jonas` instead of `Mike` in all future sessions

useRerender

Run a callback only on rerenders (if dependencies changed), but not on initial mount

Kind: global constant

Example

useRerender(() => {
  props.onChange(value);
}, [value]);

useTimeout

Run a callback function after waiting for a specified duration

Kind: global constant

Example

useTimeout(
  () => {
    console.log(`2 seconds have passed since the component was mounted`);
  },
  2000,
  null,
  useMount
);

Example

useTimeout(() => {
  console.log(
    `100 milliseconds have passed since the component was last rendered`
  );
}, 100);

Example

useTimeout(
  () => {
    console.log(`0.5 seconds have passed since myVar was last changed`);
  },
  500,
  [myVar],
  useRerender
);

License

MIT © 2019 Jonas Gierer