brother_print_library #

Flutter Android plugin for wrapping BrotherPrintLibrary.aar.

The package exposes a Dart API over Brother printer discovery, channel opening, image/PDF/PRN/raw-data printing, print cancellation, and printer status queries. It is Android-only because the bundled SDK is an Android AAR.

Installation #

dependencies:
  brother_print_library: ^0.1.4

Android apps must request runtime permissions required by the transport they use. The plugin manifest declares common network, Bluetooth, BLE, and USB features, but Android 6+ and Android 12+ still require the host app to request runtime permissions such as location, BLUETOOTH_SCAN, and BLUETOOTH_CONNECT.

Usage #

final brother = BrotherPrintLibrary();

final search = await brother.searchNetwork(durationSeconds: 5);
final channel = search.channels.first;

final open = await brother.openChannel(channel);
if (!open.success) {
  throw StateError(open.error?.code ?? 'Open channel failed');
}

final settings = BrotherPrintSettings(
  printerModel: PrinterModel.QL_820NWB,
  settingsType: 'QL',
  options: <String, Object?>{
    'labelSize': 'RollW62',
    'numCopies': 1,
    'autoCut': true,
    'scaleMode': 'FitPaperAspect',
  },
);

final result = await brother.printImage('/storage/emulated/0/Download/label.png', settings);
if (!result.success) {
  throw StateError(result.error?.description ?? result.error?.code ?? 'Print failed');
}

await brother.closeChannel();

Print encoded image bytes through the Android Bitmap overload:

final imageBytes = await labelTemplate.imageBytes;

final result = await brother.printImageBytes(imageBytes, settings);
if (!result.success) {
  throw StateError(result.error?.description ?? result.error?.code ?? 'Print failed');
}

Read typed printer status:

final statusResult = await brother.getPrinterStatus();
final status = statusResult.status;

if (statusResult.success && status != null) {
  final model = status.model;
  final errorCode = status.errorCode;
  final labelSize = status.mediaInfo?.qlLabelSize;
  final batteryLevel = status.batteryStatus?.chargeLevel?.current;
}

You can also open a known printer directly:

await brother.openChannel(BrotherChannel.wifi('192.168.1.100'));
await brother.openChannel(BrotherChannel.bluetooth('00:11:22:33:44:55'));
await brother.openChannel(BrotherChannel.bluetoothLowEnergy('local-name-or-address'));
await brother.openChannel(BrotherChannel.usb());

Print Settings #

BrotherPrintSettings.printerModel uses the typed PrinterModel enum. The enum names match Brother SDK PrinterModel names, for example PrinterModel.QL_820NWB.

BrotherPrintSettings forwards options to the Android SDK. Option enum values must match Brother SDK names exactly. Common image fields include:

scaleMode, scaleValue, orientation, rotation, halftone, hAlignment, vAlignment, compress, halftoneThreshold, numCopies, skipStatusCheck, printQuality, and trimTrailingBlankData.

If workPath is not provided, Android uses an internal app cache directory. You can still override it with options: {'workPath': '/path/to/work/dir'}.

Series-specific fields currently supported:

QL: labelSize, autoCut, cutAtEnd, resolution, autoCutForEachPageCount, biColorRedEnhancement, biColorGreenEnhancement, biColorBlueEnhancement, feedDirectionMargins, workPath.

PT: labelSize, cutmarkPrint, cutPause, autoCut, halfCut, chainPrint, specialTapePrint, resolution, autoCutForEachPageCount, forceVanishingMargin, feedDirectionMargins, workPath.

PJ: paperSize, paperType, paperInsertionPosition, feedMode, extraFeedDots, density, rollCase, printSpeed, usingCarbonCopyPaper, printDashLine, workPath, forceStretchPrintableArea.

TD: density, peelLabel, workPath, autoCut, cutAtEnd, autoCutForEachPageCount, feedDirectionMargins, customRecord.

RJ: density, rotate180degrees, peelLabel, feedDirectionMargins, workPath.

MW: paperSize, workPath.

Printer Status #

getPrinterStatus() returns BrotherStatusResult. Its status property is a BrotherPrinterStatus? with fields matching Brother SDK PrinterStatus:

rawData, model, errorCode, mediaInfo, and batteryStatus.

mediaInfo is parsed as BrotherPrinterMediaInfo; batteryStatus is parsed as BrotherPrinterBatteryStatus.

Bundled SDK #

This package includes android/libs/BrotherPrintLibrary.aar. Before publishing or distributing this package, confirm that your Brother SDK license permits redistribution through pub.flutter-io.cn or your private package registry.