Sunmi Flutter Helper Plugin #

A Flutter plugin for printing rich thermal receipts on Sunmi Android devices, supporting text, QR codes, barcodes, images, columns, scanner, and NFC features.

Supports:

• Text (with styling)
• QR Code
• Barcode
• Bitmap image
• Dividing lines (solid, dotted, empty)
• Column layout (e.g. item, qty, price)
• NFC reading (RTD_TEXT and RTD_URI)
• Barcode/QR scanning via broadcast

🚀 Getting Started #

1. Add to pubspec.yaml #

dependencies:
  sunmi_flutter_helper: ^0.0.2

2. Android Setup #

Ensure your app is running on a Sunmi device with Android. Add permissions if required:

<uses-permission android:name="android.permission.BLUETOOTH" />

3. Assets (Optional - for image printing) #

flutter:
  assets:
    - assets/images/logo.jpg

🖨 Features & Usage #

✅ Check Printer Connection #

bool isConnected = await SunmiFlutterHelper.isPrinterConnected();

📝 Print Text #

await SunmiFlutterHelper.printText({
  'text': "Welcome to Sunmi",
  'align': "center",
  'bold': true,
  'underline': true,
  'size': 18,
});

📦 Print QR Code #

await SunmiFlutterHelper.printQrCode({
  'qrText': 'https://yourdomain.com',
  'align': 'center',
  'width': 250,
  'height': 250,
});

🧾 Print Barcode #

await SunmiFlutterHelper.printBarcode({
  "data": "123456789012",
  "align": "center",
  "width": 300,
  "height": 100,
  "readable": "TWO" // Options: ONE, TWO, THREE
});

🖼 Print Image #

Uint8List bytes = await loadImageAsset('assets/images/logo.jpg');
await SunmiFlutterHelper.printImage({
  "image": bytes,
  "align": "center",
  "width": 384 // auto-maintains aspect ratio
});

🧱 Print Dividing Line #

await SunmiFlutterHelper.printLine({'type': 'solid', 'height': 4});
await SunmiFlutterHelper.printLine({'type': 'dotted', 'height': 2});
await SunmiFlutterHelper.printLine({'type': 'empty', 'height': 10});

📊 Print Table Columns #

await SunmiFlutterHelper.printColumns({
  'texts': ['Item', 'Qty', 'Amount'],
  'weights': [3, 1, 2],
  'align': 'right'
});

🔍 Scanner Support #

Listen to scanned barcode/QR code data using Sunmi scanner broadcast mode.

StreamSubscription? scanSubscription;

void startScanListener() {
  scanSubscription = EventChannel("sunmi_flutter_helper/scanStream")
      .receiveBroadcastStream()
      .listen((data) {
    print("Scanned code: \$data");
  });
}

void stopScanListener() {
  scanSubscription?.cancel();
}

📶 NFC Reader Support #

Read NFC tags (RTD_TEXT or RTD_URI records).

StreamSubscription? nfcSubscription;

void startNfcListener() {
  nfcSubscription = EventChannel("sunmi_flutter_helper/nfcStream")
      .receiveBroadcastStream()
      .listen((data) {
    print("NFC Data: \$data"); // May be a list of text and/or URI
  });
}

void stopNfcListener() {
  nfcSubscription?.cancel();
}

🛠 Available Parameters #

🔤 Text Printing (printText) #

📏 Dividing Line (printLine) #

📦 QR Code (printQrCode) #

🧾 Barcode (printBarcode) #

🖼 Image (printImage) #

📊 Columns (printColumns) #

📌 Requirements #

• Android 11+
• Tested on: Sunmi Android devices
• Flutter 3.0+

👨‍💻 Maintainer #

4Brains Technologies
https://www.4brains.in
For support or customization: [email protected]

📃 License #

MIT License