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useSync

A subscription based state management solution for React!

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Table of Contents

• Installation
• Usage
• Notes
• License

Installation:

Install the package from npm:

$ npm install usesync --save

Then simply require it:

const { useSync, sync, storage } = require("usesync") // CJS

or

import useSync, { sync, storage } from "usesync" // ESM

Usage:

useSync(id: string, initialValue?: any): any

This is the hook that you will use across your React components, it allows them to subscribe to a specific sync with the ID you give:

const Component = () => {
    useSync('hello')
    return (
        <div>
            Hello World!
        </div>
    )
}

Subscribing to muiltiple syncs is possible, just call the hook multiple times with different IDs:

const Component = () => {
    useSync('id num 1')
    useSync('id num 2')
    return (
        <div>
            Hello World!
        </div>
    )
}

Updating sync IDs at runtime is allowed:

const GreetUser = (id) => {
    const user = getUser(id)
    useSync(`Users ${id}`)
    return (
        <div>
            Hello {user.firstName}!
        </div>
    )
}

To synchronize state in multiple components simply call the hook inside all of them and give the same ID:

const ComponentA = () => {
    const name = useSync('hello', 'World')
    return (
        <div>
            Hello {name}! (A)
        </div>
    )
}
const ComponentB = () => {
    const name = useSync('hello', 'World')
    return (
        <div>
            Hello {name}! (B)
        </div>
    )
}

sync(id: string, newValue?: any): void

The hook alone does nothing, to dispatch a sync you need to call this function, this will cause all the subscribed components to re-render. Here is an example:

import React from 'react'
import ReactDOM from 'react-dom'
import useSync, { sync } from "usesync"


const ComponentA = () => {
    useSync('Components')
    return (
        <div>
            Random Number (A): {Math.random()}
        </div>
    )
}
const ComponentB = () => {
    useSync('Components')
    useSync('ComponentB')
    return (
        <div>
            Random Number (B): {Math.random()}
        </div>
    )
}
const ComponentC = () => {
    useSync('Components')
    return (
        <div>
            Random Number (C): {Math.random()}
        </div>
    )
}
const App = () => {
    const handleClick = () => {
        sync('Components')
    }
    const handleClick2 = () => {
        sync('ComponentB')
    }
    return (
        <div>
            <ComponentA />
            <ComponentB />
            <ComponentC />
            <ComponentC />
            <button onClick={handleClick}>re-render all</button>
            <button onClick={handleClick2}>re-render component b</button>
        </div>
    )
}

ReactDOM.render(<App />, document.getElementById('app'))

Try it on CodePen!

New: You may pass a sync value to this function, and access it from the subscribed components:

import React from 'react'
import ReactDOM from 'react-dom'
import useSync, { sync } from "usesync"


const initialValue = Math.random()

const ComponentA = () => {
    const randomNumber = useSync('Components', initialValue)
    return (
        <div>
            Random Number (A): {randomNumber}
        </div>
    )
}
const ComponentB = () => {
    const randomNumber = useSync('Components', initialValue)
    return (
        <div>
            Random Number (B): {randomNumber}
        </div>
    )
}
const ComponentC = () => {
    const randomNumber = useSync('Components', initialValue)
    return (
        <div>
            Random Number (C): {randomNumber}
        </div>
    )
}
const App = () => {
    const handleClick = () => {
        sync('Components', Math.random())
    }
    return (
        <div>
            <ComponentA />
            <ComponentB />
            <ComponentC />
            <ComponentC />
            <button onClick={handleClick}>re-render all</button>
        </div>
    )
}

ReactDOM.render(<App />, document.getElementById('app'))

Try it on CodePen!

storage: Object

This is an optional object that is globaly available across your app, it can be used to store states for your componenets. Here is an example:

import React from 'react'
import ReactDOM from 'react-dom'
import useSync, { sync, storage } from "usesync"


storage.randomNumber = Math.random()

const ComponentA = () => {
    useSync('Components')
    return (
        <div>
            Random Number (A): {storage.randomNumber}
        </div>
    )
}
const ComponentB = () => {
    useSync('Components')
    useSync('ComponentB')
    return (
        <div>
            Random Number (B): {storage.randomNumber}
        </div>
    )
}
const ComponentC = () => {
    useSync('Components')
    return (
        <div>
            Random Number (C): {storage.randomNumber}
        </div>
    )
}
const App = () => {
    const handleClick = () => {
        storage.randomNumber = Math.random()
        sync('Components')
    }
    const handleClick2 = () => {
        storage.randomNumber = Math.random()
        sync('ComponentB')
    }
    return (
        <div>
            <ComponentA />
            <ComponentB />
            <ComponentC />
            <ComponentC />
            <button onClick={handleClick}>re-render all</button>
            <button onClick={handleClick2}>re-render component b</button>
        </div>
    )
}

ReactDOM.render(<App />, document.getElementById('app'))

Try it on CodePen!

Notes

Give this cool project a star ⭐! I will appreciate it ❤

License

MIT © iMrDJAi