use-prop-change v0.1.4

use-prop-change

use-prop-change React hook for simplifying setState decomposition into smaller setters for particular state parts. It can usefull when you need:

• transfer control over part of the state to another component;
• set or change some data in nested state tree;
• simplify working with forms without big library;

example on codesandbox

Install

$ npm install use-prop-change

or

$ yarn add use-prop-change

Usage Example

import React, { useState } from "react";
import usePropChange from "use-prop-change";

import Friends from "./Friends"; // this component responsible for friends field

const forInput = (handler) => (e) => handler(e.target.value);

const defaultPerson = {
  name: "Dasha",
  age: "23",
  friends: [
    /* whatever here */
  ],
};

export const PersonForm = () => {
  const [person, setPerson] = useState(defaultPerson);

  const handlePersonProp = usePropChange(setPerson);

  return (
    <form onSubmit={/* do something */}>
      <input
        value={person.name}
        onChange={forInput(handlePersonProp("name"))}
      />
      <input value={person.age} onChange={forInput(handlePersonProp("age"))} />
      <Friends
        friends={person.friends}
        onFriendsChange={handlePersonProp("friends")}
      />
    </form>
  );
};

How it works?

use-prop-change use ramda lens under the hood. But you don't need understand them to use this hook.

For example above we can replace

const handlePersonProp = usePropChange(setPerson);

to

const handlePersonProp = (name) => (value) => {
  setPerson((prevState) => ({
    ...prevState,
    [name]: typeof value === "function" ? value(prevState[name]) : value,
  }));
};

But note, handlePersonProp returned from usePropChange more powerfull:

• if first argument is number, new state will be an Array
• if first argument is string, new state will be an Object
• if first argument is array, state will be changed on this path
• 2 arguments (name and value) can be passed together, to just make changes once

You can see all this on example