# react-native-citizen-escposprinter

A React Native wrapper of the
[Citizen ECSPOSPrinter SDK](https://www.citizen-systems.co.jp/en/printer/download),
supporting the
[New Architecture](https://reactnative.dev/docs/the-new-architecture/landing-page)
and classic builds.

The current version embeds these SDKs:

1. [CSJAndroidPOSSDK_V212E.zip](https://www.citizen-systems.co.jp/cms/c-s/en/printer/download/sdk-print/CSJAndroidPOSSDK_V212E.zip)
1. [CSJiOSSwiftSDK_V212E.zip](https://www.citizen-systems.co.jp/cms/c-s/en/printer/download/sdk-print/CSJiOSSwiftSDK_V212E.zip)

## Usage

Most of the methods are a simple wrapper of the native SDK. For a complete list
of methods and their details, you may refer to the PDF manual inside the
[Citizen SDK](https://www.citizen-systems.co.jp/en/printer/download).

```tsx
import {
  connect,
  ESCPOSConst,
  searchCitizenPrinters,
} from "react-native-citizen-escposprinter";

const main = async () => {
  const results = await searchCitizenPrinters(
    ESCPOSConst.CMP_PORT_WiFi,
  );
  console.info("Found printers:", results);

  const printer = await connect(
    ESCPOSConst.CMP_PORT_WiFi,
    results[0].ipAddress
  );
  await printer.printText("Hello World!\n");
  await printer.cutPaper(ESCPOSConst.CMP_CUT_FULL_PREFEED);
  await printer.disconnect();
};
```

## ⚠️ Known Issues

### Error `RCTEvents.receiveEvent() is not registered`

tl;dr Do not use `index.tsx` as your entrypoint, use something like `app.tsx`
instead.

This error happens when all of the following conditions are met:

1. You have `expo-router` installed
2. You have new architecture enabled
3. You are using `index.tsx` as your entrypoint

When expo-router's own modified entrypoint sees your `index.tsx`, it will be
confused and incorrectly overrides some native modules.

### Partial USB Support

USB connections without specified a serial number is supported and tested in the
following environments (see
[#7](https://github.com/vicary/react-native-citizen-escposprinter/pull/7)):

1. Android in "old" architecture
2. Android in
   [New Architecture](https://reactnative.dev/docs/the-new-architecture/landing-page)

## Contributing

See the [contributing guide](CONTRIBUTING.md) to learn how to contribute to the
repository and the development workflow.

If you use this library at work, consider
[sponsoring](https://github.com/sponsors/vicary) for a first-class technical
support.