README

react-piano

An interactive piano keyboard for React. Supports custom sounds, touch/click/keyboard events, and fully configurable styling. Try it out on CodeSandbox.

Installing

yarn add react-piano

Alternatively, you can download the UMD build from unpkg.

Usage

You can view or fork the CodeSandbox demo to get a live version of the component in action.

Import the component and styles:

import { Piano, KeyboardShortcuts, MidiNumbers } from 'react-piano';
import 'react-piano/dist/styles.css';

Importing CSS requires a CSS loader (if you're using create-react-app, this is already set up for you). If you don't have a CSS loader, you can alternatively copy the CSS file into your project from src/styles.css.

Then to use the component:

function App() {
  const firstNote = MidiNumbers.fromNote('c3');
  const lastNote = MidiNumbers.fromNote('f5');
  const keyboardShortcuts = KeyboardShortcuts.create({
    firstNote: firstNote,
    lastNote: lastNote,
    keyboardConfig: KeyboardShortcuts.HOME_ROW,
  });

  return (
    <Piano
      noteRange={{ first: firstNote, last: lastNote }}
      playNote={(midiNumber) => {
        // Play a given note - see notes below
      }}
      stopNote={(midiNumber) => {
        // Stop playing a given note - see notes below
      }}
      width={1000}
      keyboardShortcuts={keyboardShortcuts}
    />
  );
}

Implementing audio playback

react-piano does not implement audio playback of each note, so you have to implement it with playNote and stopNote props. This gives you the ability to use any sounds you'd like with the rendered piano. The react-piano demo page uses @danigb's excellent soundfont-player to play realistic-sounding soundfont samples. Take a look at the CodeSandbox demo to see how you can implement that yourself.

Props

Name	Type	Description
`noteRange`	Required object	An object with format `{ first: 48, last: 77 }` where first and last are MIDI numbers that correspond to natural notes. You can use `MidiNumbers.NATURAL_MIDI_NUMBERS` to identify whether a number is a natural note or not.
`playNote`	Required function	`(midiNumber) => void` function to play a note specified by MIDI number.
`stopNote`	Required function	`(midiNumber) => void` function to stop playing a note.
`width`	Conditionally required number	Width in pixels of the component. While this is not strictly required, if you omit it, the container around the `<Piano>` will need to have an explicit width and height in order to render correctly.
`activeNotes`	Array of numbers	An array of MIDI numbers, e.g. `[44, 47, 54]`, which allows you to programmatically play notes on the piano.
`keyWidthToHeight`	Number	Ratio of key width to height. Used to specify the dimensions of the piano key.
`renderNoteLabel`	Function	`({ keyboardShortcut, midiNumber, isActive, isAccidental }) => node` function to render a label on piano keys that have keyboard shortcuts
`className`	String	A className to add to the component.
`disabled`	Boolean	Whether to show disabled state. Useful when audio sounds need to be asynchronously loaded.
`keyboardShortcuts`	Array of object	An array of form `[{ key: 'a', midiNumber: 48 }, ...]`, where `key` is a `keyEvent.key` value. You can generate this using `KeyboardShortcuts.create`, or use your own method to generate it. You can omit it if you don't want to use keyboard shortcuts. Note: this shouldn't be generated inline in JSX because it can cause problems when diffing for shortcut changes.
`onPlayNoteInput`	Function	`(midiNumber, { prevActiveNotes }) => void` function that fires whenever a play-note event is fired. Can use `prevActiveNotes` to record notes.
`onStopNoteInput`	Function	`(midiNumber, { prevActiveNotes }) => void` function that fires whenever a stop-note event is fired. Can use `prevActiveNotes` to record notes.

Recording/saving notes

You can "record" notes that are played on a <Piano> by using onPlayNoteInput or onStopNoteInput, and you can then play back the recording by using activeNotes. See this CodeSandbox which demonstrates how to set that up.

Customizing styles

You can customize many aspects of the piano using CSS. In javascript, you can override the base styles by creating your own set of overrides:

import 'react-piano/dist/styles.css';
import './customPianoStyles.css';  // import a set of overrides

In the CSS file you can do things like:

.ReactPiano__Key--active {
  background: #f00;  /* Change the default active key color to bright red */
}

.ReactPiano__Key--accidental {
  background: #000;  /* Change accidental keys to be completely black */
}

See styles.css for more detail on what styles can be customized.

Upgrading versions

See the CHANGELOG which contains migration guides for instructions on upgrading to each major version.

Browser compatibility

To support IE, you'll need to provide an Array.find polyfill.

License

MIT

Usage no npm install needed!