A set of tiny, composable React components
for handling state with render props.
Why? · Principles · Examples · Documentation · Contributing!
react-values gives you a set of simple, composable helpers that let you build more complex, stateful UI components like toggles, dropdowns, lists, checkbox groups, popovers, tooltips, you name it!
It does this using a small render-prop-based API that exposes helpful transforms like
Anyvalues provide simple transforms like
Arrayvalues provide native methods like
toggle, which we've all re-implemented 100 times.
Datevalues provide really helpful transforms like
Mapvalues provide native methods like
decrement, which have also been re-written in every codebase ever.
Objectvalues provide helpful transforms like
Setvalues provide native methods like
Stringvalues provide native methods like
This saves you from constantly re-writing the same state management logic, so you can keep your components focused on behavior and presentation.
For example, here's the classic state management "counter" example:
import NumberValue from 'react-values'const Counter =<NumberValue =>value increment decrement<button =>+1</button><span>value</span><button =>-1</button></NumberValue>
Of going further, here's a full fledged
value/defaultValue and providing
onChange) implemented in just a few lines of code using a
import BooleanValue from 'react-values'const Toggle = value defaultValue onChange<BooleanValue = = =>value: on toggle<Track = =><Thumb = /></Track></BooleanValue>const Track = styleddiv`position: relative;height: 25px;width: 50px;background-color: ;border-radius: 50px;`const Thumb = styleddiv`position: absolute;left: ;height: 25px;width: 25px;background-color: white;border-radius: 50px;`
But you can go further, because
react-values can "connect" a single value across multiple components. This is helpful any time you need a "global" piece of state in your app, without wanting to add tons of complexity.
For example, using the
<Toggle> from above, here's a modal you can open and close from anywhere in your app:
import createBooleanValue from 'react-values'import Modal Toggle from './ui'const ModalValue =const App =<div ="app"><div ="sidebar"><ModalValue>value set<Toggle = = /></ModalValue></div><div ="content"><ModalValue>value: openedopened && <Modal /></ModalValue></div><div>
react-values gives you seem simple at first, but they can be composed together to create complex behaviors that are still easy to reason about, in just a few lines of code.
While building an app with React, you end up building a lot of stateful components in the process. Whether at the UI kit level for things like toggles, tooltips, checkbox groups, dropdown, etc. Or at the app level for modals, popovers, sorting, filtering, etc.
In the process, you end up re-implementing run of the mill state handling logic all over the place—whether with
this.setState or by adopting some "state management framework" and writing the same boilerplate over and over again. And for your components to be nicely reusable across your application you augment them to handle both "controlled" and "uncontrolled" use cases using
defaultValue. And to make things a bit more manageable, you re-invent common transforms like
decrement, etc. in lots of different components. And if you're working with a team, you end up doing all of this in slightly different ways throughout your codebase.
In the end, you're now maintaing a lot more logic than necessary, duplicated in many different places in slightly different ways. It gets harder and harder to understand your app's data flow. All while your app's bundle size grows.
react-values solves all of that with a few principles...
Leverage render props. It uses a render-prop-based API, exposing its state and a handful of convenient transform functions to you with the flexible function-as-children pattern.
Follow React's conventions. Its components follow React's own naming conventions, using familiar concepts like
value/defaultValue. This makes it extremely easy to slot into existing codebases or frameworks.
concat, etc. to avoid reinventing the wheel and forcing you to constantly read documentation.
Be extremely lightweight. It's extremely lightweight (and tree-shakeable), with most components weighing just a few hundred bytes, so you can even import it from public-facing component libraries.
Prioritize convenience. It's designed to provide convenient functions like
toggle, and smarter ones like
decrementMonth, so you can build complex interactions in just a few lines of code.
To get a sense for how you might use
react-values, check out a few of the examples:
- Basic Toggle — using a
Booleanto create a simple toggle component.
- Reusable Toggle — showing how you might turn that toggle into a controlled component in your own UI kit.
- Counter — a simple counter using a
Numberand its convenience transforms.
- Connected Counters — two counters that are connected together, sharing a single value.
- Time Picker — a more complex time picker component, using
Dateand its convenience transforms.
- Filtering — a basic
Stringvalue used for filtering a list.
- Checkbox Set — using a
Setto keep track of a checkbox group.
- Simple Tooltip — a simplistic tooltip implemented as a
- Simple Modal — a simplistic modal implemented as a
- Connected Modal — a modal whose opened/closed state is controllable from other components.
If you have an idea for an example that shows a common use case, pull request it!
If you're using
react-values for the first time, check out the Getting Started guide to familiarize yourself with how it works. Once you've done that, you'll probably want to check out the full API Reference.
- Getting Started
If even that's not enough, you can always read the source itself.
There are also translations of the documentation into other languages:
If you're maintaining a translation, feel free to pull request it here!
All contributions are super welcome! Check out the Contributing instructions for more info!
react-values is MIT-licensed.