vexflow-native

React Native Skia bridge for rendering VexFlow music notation.

Installation

Install the library and its peer dependencies:

npm install vexflow-native react react-native vexflow @shopify/react-native-skia react-native-gesture-handler react-native-reanimated react-native-worklets

ScoreRenderer uses gesture handling and Reanimated worklets for scrolling, so configure react-native-gesture-handler, react-native-reanimated, and react-native-worklets as required by your React Native app.

Entrypoints

• vexflow-native exports the low-level VexflowCanvas bridge for drawing with VexFlow directly.
• vexflow-native/renderer exports ScoreRenderer, a React component that renders the typed score model.
• vexflow-native/state exports the score state types, including Score.
• vexflow-native/musicxml exports parseMusicXmlToScore and MusicXmlParseError.

Fonts

Load a notation font with Skia and pass the returned font provider to the renderer. The defaultFont prop must match one of the font family names passed to useFonts.

import { useFonts } from '@shopify/react-native-skia';

import bravuraFont from './assets/fonts/Bravura.otf';

const fontManager = useFonts({
  Bravura: [bravuraFont],
});

if (!fontManager) {
  return null;
}

React Native Skia web patches

The example app includes a patch-package patch for @shopify/react-native-skia@2.6.2 at example/patches/@shopify+react-native-skia+2.6.2.patch. The repository root applies it after install with:

yarn workspace vexflow-native-example apply-patches

The patch is needed by the web example with this Skia version. It:

• lets Skia web resolve string asset sources;
• forwards JsiSkTypefaceFontProvider.matchFamilyStyle to CanvasKit so fonts registered with useFonts can be matched by family name;
• keeps a small diagnostic log in the web font manager patch.

Native iOS and Android usage does not need this example patch. If your own app targets React Native Web with @shopify/react-native-skia@2.6.2 and hits font matching or asset source issues, apply an equivalent patch in your app with patch-package. Re-check the patch when upgrading Skia, because it is tied to that package version and may become unnecessary after upstream changes.

Render MusicXML

Convert a MusicXML string into a Score, then render it with ScoreRenderer.

import React, { useMemo } from 'react';
import { View } from 'react-native';
import { useFonts } from '@shopify/react-native-skia';
import { ScoreRenderer } from 'vexflow-native/renderer';
import {
  MusicXmlParseError,
  parseMusicXmlToScore,
} from 'vexflow-native/musicxml';

import bravuraFont from './assets/fonts/Bravura.otf';

type MusicXmlScoreProps = {
  xml: string;
};

export function MusicXmlScore({ xml }: MusicXmlScoreProps) {
  const fontManager = useFonts({
    Bravura: [bravuraFont],
  });
  const score = useMemo(
    () => parseMusicXmlToScore(xml, { scoreId: 'imported-score' }),
    [xml]
  );

  if (!fontManager) {
    return null;
  }

  return (
    <View style={{ flex: 1 }}>
      <ScoreRenderer
        score={score}
        defaultFont="Bravura"
        fontManager={fontManager}
      />
    </View>
  );
}

try {
  parseMusicXmlToScore('<score-timewise />');
} catch (error) {
  if (error instanceof MusicXmlParseError) {
    // The current parser targets score-partwise MusicXML.
  }
}

The MusicXML parser currently targets score-partwise documents. score-timewise input throws MusicXmlParseError.

Render a Plain Score Object

Use ScoreRenderer directly when you already have score state or want to build it yourself.

import React from 'react';
import { View } from 'react-native';
import { useFonts } from '@shopify/react-native-skia';
import { ScoreRenderer } from 'vexflow-native/renderer';
import type { Score } from 'vexflow-native/state';

import bravuraFont from './assets/fonts/Bravura.otf';

const score: Score = {
  id: 'plain-score',
  defaults: {
    meter: {
      beats: 4,
      beatUnit: 4,
    },
    keySignature: {
      tonic: 'C',
      mode: 'major',
    },
  },
  staves: [
    {
      id: 'staff-1',
      order: 0,
      defaultClef: 'treble',
      measures: [
        {
          id: 'measure-1',
          number: 1,
          leftModifiers: {
            showClef: true,
            showKeySignature: true,
            showMeter: true,
          },
          voices: [
            {
              id: 'voice-1',
              index: 0,
              items: [
                {
                  id: 'note-1',
                  type: 'note',
                  pitch: { step: 'C', octave: 4 },
                  duration: { length: 'q' },
                  voiceId: 'voice-1',
                },
                {
                  id: 'note-2',
                  type: 'note',
                  pitch: { step: 'D', octave: 4 },
                  duration: { length: 'q' },
                  voiceId: 'voice-1',
                },
                {
                  id: 'note-3',
                  type: 'note',
                  pitch: { step: 'E', octave: 4 },
                  duration: { length: 'q' },
                  voiceId: 'voice-1',
                },
                {
                  id: 'note-4',
                  type: 'note',
                  pitch: { step: 'F', octave: 4 },
                  duration: { length: 'q' },
                  voiceId: 'voice-1',
                },
              ],
            },
          ],
        },
      ],
    },
  ],
};

export function PlainScore() {
  const fontManager = useFonts({
    Bravura: [bravuraFont],
  });

  if (!fontManager) {
    return null;
  }

  return (
    <View style={{ flex: 1 }}>
      <ScoreRenderer
        score={score}
        defaultFont="Bravura"
        fontManager={fontManager}
        rendererType="document"
      />
    </View>
  );
}

rendererType is optional. The default is document; use documentEven for even measure widths across document systems, or infiniteScore for a horizontal single-system layout.

Draw Directly with VexFlow

Use VexflowCanvas when you want direct VexFlow control instead of the typed score model.

import React, { useCallback } from 'react';
import { View } from 'react-native';
import { useFonts } from '@shopify/react-native-skia';
import { Formatter, Stave, StaveNote, Voice } from 'vexflow';
import { VexflowCanvas, type OnDrawParams } from 'vexflow-native';

import bravuraFont from './assets/fonts/Bravura.otf';

export function DirectVexFlow() {
  const fontManager = useFonts({
    Bravura: [bravuraFont],
  });

  const onDraw = useCallback(({ ctx }: OnDrawParams) => {
    const stave = new Stave(10, 40, 400);

    stave.addClef('treble').addTimeSignature('4/4');

    const notes = [
      new StaveNote({ keys: ['c/4'], duration: 'q' }),
      new StaveNote({ keys: ['d/4'], duration: 'q' }),
      new StaveNote({ keys: ['e/4'], duration: 'q' }),
      new StaveNote({ keys: ['f/4'], duration: 'q' }),
    ];

    const voice = new Voice({ numBeats: 4, beatValue: 4 });
    voice.addTickables(notes);

    new Formatter().joinVoices([voice]).formatToStave([voice], stave);

    stave.setContext(ctx).draw();
    voice.draw(ctx, stave);
  }, []);

  if (!fontManager) {
    return null;
  }

  return (
    <View style={{ flex: 1 }}>
      <VexflowCanvas
        onDraw={onDraw}
        fontManager={fontManager}
        defaultFont="Bravura"
      />
    </View>
  );
}

ScoreRenderer props

• score: typed score state to render.
• defaultFont: font family name used as the default VexFlow font.
• fontManager: Skia font provider returned by useFonts.
• colorScheme: optional foreground, background, and ledger line colors.
• rendererType: document, documentEven, or infiniteScore.
• options: optional renderer settings grouped by insets, spacing, and render.
• scrollEnabled: enables or disables pan scrolling. Defaults to true.
• showScrollbars: shows scrollbars when the score overflows. Defaults to true.

Contributing

• Development workflow
• Sending a pull request
• Code of conduct

License

MIT