react-async-ui

This package provides state management primitives to build modal user interactions that you can await, resolve and reject using a familiar, Promise-based API.

Design goals

• Provide lightweight building blocks to express modal UI behavior as async/await workflows
• Provide a headless hooks-based API that keeps you flexible in your choice of UI component library and styling solution
• Provide first-class TypeScript support and documentation

Installation

npm install react-async-ui

API

The react-async-ui package exports the useAsyncModalState hook to manage the lifecycle of a modal UI element that can be shown, await'ed, and can optionally accept parameters and return a result to the caller.

const [state, showModal] = useAsyncModalState<TValue, TResult>()

Similar to React's setState hook, it returns an array with exactly two elements:

• state: Represents the current interaction state. This object has the following properties:

  Name	Description
  isOpen	true if the modal is open, false otherwise
  props	(Only available when isOpen is true)
  props.value	The (optional) parameter passed to showModal()
  props.resolve()	Completes the modal interaction. Takes an optional result parameter that will be returned from showModal().
  props.reject()	Fails the modal interaction with an exception. Takes an optional reason parameter that will be thrown from showModal().

• showModal(): A callback to open the modal and optionally pass along a parameter value. It returns a Promise object, so you can await it to obtain the result of the modal interaction when the modal component calls state.props.{resolve|reject}:

  const result = await showModal(42)

Example

Let's build a simple greeter dialog that takes a single string argument (i.e., the name of the person to greet) and can be dismissed through "OK" and "Cancel" buttons:

import { useAsyncModalState } from 'react-async-ui'

function App() {
  // Declare state for a modal interaction that takes a string
  // argument and completes with either 'ok' or 'cancel'
  const [state, showModal] = useAsyncModalState<string, 'ok' | 'cancel'>()

  const sayHello = async () => {
    const result = await showModal('world')

    if (result === 'ok') {
      // TODO: Handle "ok" result
    }
  }

  return (
    <>
      <button onClick={sayHello}>
        Say hello!
      </button>

      {/* Only render dialog when state says it's open */}
      {state.isOpen && <GreeterDialog {...state.props} />}
    </>
  )
}

The corresponding dialog component then uses state.props to access the passed value and return a result through showModal:

import { AsyncModalProps } from 'react-async-ui'

function GreeterDialog({ value, resolve }: AsyncModalProps<string, 'ok' | 'cancel'>) {
  return (
    <dialog open>
      <p>Hello, {value}!</p>
      <button onClick={() => resolve('ok')}> OK </button>
      <button onClick={() => resolve('cancel')}> Cancel </button>
    </dialog>
  )
}