@mitsuharu/react-native-sunmi-printer-library

React Native module that supports for SUNMI mobile printer devices.

Verification devices

I validate it with GMS enable and developable SUNMI V2 PRO and SUNMI V2s as follows. Though I do not have other devices, users report to work with V1s and V2.

	Android	SUNMI OS	firmware	storage	memory	NFC
SUNMI V2 PRO	7.1	3.6.23	754	16 GB	2 GB	enable
SUNMI V2 PRO (foodpanda)	7.1	1.0.33	138	8 GB	1 GB	disable
SUNMI V2s	11	3.0.11	242	32 GB	3 GB	enable

Installation

React Native

npm install @mitsuharu/react-native-sunmi-printer-library

or

yarn add @mitsuharu/react-native-sunmi-printer-library

Expo

This package contains custom Android native code, so it does not work in Expo Go. Install it in an Expo project that uses a development build:

yarn expo install expo-dev-client @mitsuharu/react-native-sunmi-printer-library

Regenerate the Android project after installing or updating the package, then compile and install it locally. An EAS Build or Expo account is not required:

yarn expo prebuild --platform android --clean
yarn expo run:android --device

See Expo's development build documentation for details. This library supports Android only.

Usage

See the React Native example in example/ or the Expo example in example-expo/ for details.

prepare

import * as SunmiPrinterLibrary from '@mitsuharu/react-native-sunmi-printer-library'

try {
    await SunmiPrinterLibrary.prepare()
} catch (error: any) {
    console.warn("This device is not supported.")
}

print Text

await SunmiPrinterLibrary.printText('Hello World')

or

SunmiPrinterLibrary.printText('Hello World')

Warning

Printing without await is faster, but may be interrupted by other printing. When it use without await, it is better to use with Transaction.

change style

await SunmiPrinterLibrary.setAlignment('center')
await SunmiPrinterLibrary.setTextStyle('bold', true)
await SunmiPrinterLibrary.setParagraphStyle('textRightSpacing', 5)
await SunmiPrinterLibrary.setFontSize(32)
await SunmiPrinterLibrary.printText('Hello World')

print Image (Base64)

const base64 = 'data:image/png;base64,iVBORw0KGgoAAAA...'
await SunmiPrinterLibrary.printImage(base64, 384, 'binary')
await SunmiPrinterLibrary.printImage(base64, 384, 'grayscale')

print QR code

await SunmiPrinterLibrary.printQRCode('Hello World', 8, 'middle')

scan QR code

const result = await SunmiPrinterLibrary.scan()

or

SunmiPrinterLibrary.scan()

useEffect(() => {
   DeviceEventEmitter.addListener(
      SunmiPrinterLibrary.EventType.onScanSuccess,
      (message) => {
        console.log(`[onScanSuccess] ${message}`)
      })
   DeviceEventEmitter.addListener(
      SunmiPrinterLibrary.EventType.onScanFailed, 
      (message) => {
        console.log(`[onScanFailed] ${message}`)
      })
   return () => {
      DeviceEventEmitter.removeAllListeners(SunmiPrinterLibrary.EventType.onScanSuccess)
      DeviceEventEmitter.removeAllListeners(SunmiPrinterLibrary.EventType.onScanFailed)
    }
}, [])

Transaction

await SunmiPrinterLibrary.enterPrinterBuffer(true)

SunmiPrinterLibrary.printText('Transaction Test 0')

await SunmiPrinterLibrary.commitPrinterBuffer()

SunmiPrinterLibrary.printText('Transaction Test 1')
SunmiPrinterLibrary.printText('Transaction Test 2')
SunmiPrinterLibrary.printText('Transaction Test 3')
SunmiPrinterLibrary.lineWrap(4)

await SunmiPrinterLibrary.exitPrinterBuffer(true)

Raw Data (ESC/POS command)

// use to convert data to Base 64
import { Buffer } from 'buffer'

// ESC/POS command
// see: https://developer.sunmi.com/docs/en-US/index
const boldOn = new Uint8Array([0x1B, 0x45, 0x01])
const boldOnBase64 = Buffer.from(boldOn).toString('base64')
await SunmiPrinterLibrary.sendRAWData(boldOnBase64)

await SunmiPrinterLibrary.printText('Bold is ON')

const boldOff = new Uint8Array([0x1B, 0x45, 0x00])
const boldOffBase64= Buffer.from(boldOff).toString('base64')
await SunmiPrinterLibrary.sendRAWData(boldOffBase64)

await SunmiPrinterLibrary.printText('Bold is OFF')

not support

• Cash Drawer API
• Black Mark Print API

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

Develop

yarn
yarn example android

Examples

• example/ is the bare React Native example and uses React Native 0.87.
• example-expo/ is the Expo example and uses Expo SDK 57 with React Native 0.86.
• Both examples reuse the same printer operation screen.

The Expo example uses local Continuous Native Generation. It does not use EAS Build or any other cloud build service. Generate a fresh Android project with Expo Prebuild and build the APK with the generated Gradle Wrapper:

yarn example:expo build:android

The generated example-expo/android/ directory is intentionally ignored. Do not edit it directly; update the Expo app configuration or a config plugin and run Prebuild again.

Development builds on Android 7.x

The Expo SDK 57 development launcher uses java.time.Duration during startup. Without compatibility handling, the APK cannot resolve this API below Android 8.0 and crashes at startup on Android 7.1 devices such as the SUNMI V2 PRO:

java.lang.NoClassDefFoundError: Failed resolution of: Ljava/time/Duration;

The Expo example registers example-expo/plugins/withAndroidCoreLibraryDesugaring.js as a config plugin in app.json. During Prebuild, it enables core library desugaring and adds desugar_jdk_libs, allowing the development build to start on Android 7.x.

Do not add this configuration directly to the generated example-expo/android/app/build.gradle; expo prebuild --clean will replace that file. Keep native configuration in the config plugin instead. See the Expo config plugin documentation and Android Java API desugaring documentation for more information.

To start the Expo development server for an installed development build:

yarn example:expo start

Guides

• Create Pull Requests against the main branch.
• I recommend that add or fix test, readme and example.

Release

Maintainers only: update the version in package.json in a pull request against main. After the pull request is merged and CI succeeds, run the Release to npm workflow from the Actions tab and enter that exact version. The workflow builds and verifies the package, creates a matching tag and GitHub release, and publishes the package to npm. Merging into main never publishes a package.

License

MIT

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Made with create-react-native-library