pos_printer_d 1.0.3

A clean Flutter plugin for POS thermal printers. Supports Bluetooth, USB, and Network (TCP) connections with a simple unified API.

POS Printer D

A clean Flutter plugin for POS thermal printers. Supports Bluetooth, USB, and Network (TCP) connections.

Reference - flutter_pos_printer_platform

Features

• ✅ Bluetooth - Classic Bluetooth and BLE (Android, iOS)
• ✅ USB - Direct USB connection (Android, Windows)
• ✅ Network/TCP - Ethernet printers (All platforms)
• ✅ Simple API - Single PrinterService for all operations
• ✅ Reactive - Stream-based state management
• ✅ Type-safe - Full Dart null-safety support

Installation

Add to your pubspec.yaml:

dependencies:
  pos_printer_d: ^1.0.0

Or from Git:

dependencies:
  pos_printer_d:
    git:
      url: https://github.com/alexdlov/pos_printer.git

Quick Start

import 'package:pos_printer_d/pos_printer_d.dart';

// Get the service instance
final printerService = PrinterService.instance;

// Discover printers
await for (final device in printerService.discover(PrinterType.bluetooth)) {
  print('Found: ${device.name}');
}

// Connect to a printer
await printerService.connect(device);

// Send ESC/POS data
await printerService.send(bytes);

// Disconnect
await printerService.disconnect();

API Overview

PrinterService

Main entry point for all printer operations:

final service = PrinterService.instance;

// Check supported types
service.supportedTypes; // [bluetooth, usb, network]
service.isSupported(PrinterType.bluetooth); // true/false

// Discovery
service.discover(PrinterType.bluetooth);
service.discoverAll(); // All types at once
service.stopDiscovery();

// Connection
service.connect(device, config: ConnectionConfig.reliable);
service.connectToIp('192.168.1.100', port: 9100);
service.disconnect();
service.isConnected; // bool
service.currentDevice; // PrinterDevice?

// State
service.stateStream; // Stream<ConnectionState>
service.currentState; // ConnectionState

// Printing
service.send(bytes);
service.sendBytes(list);
service.sendText('Hello');

// ESC/POS helpers
service.initialize();
service.cut();
service.feed(3);
service.beep();

PrinterDevice

Represents a discovered printer:

// Factory constructors
PrinterDevice.bluetooth(name: 'Printer', address: 'AA:BB:CC:DD:EE:FF');
PrinterDevice.usb(name: 'USB Printer', vendorId: '1234', productId: '5678');
PrinterDevice.network(address: '192.168.1.100', port: 9100);

// Properties
device.name;        // Display name
device.type;        // PrinterType
device.address;     // MAC/IP address
device.vendorId;    // USB vendor (USB only)
device.productId;   // USB product (USB only)
device.port;        // Network port (Network only)
device.isBle;       // BLE flag (Bluetooth only)

ConnectionConfig

Configure connection behavior:

ConnectionConfig(
  timeout: Duration(seconds: 5),
  autoReconnect: false,
  discoveryTimeout: Duration(seconds: 10),
);

// Presets
ConnectionConfig.defaultConfig;
ConnectionConfig.fast;
ConnectionConfig.reliable;

ConnectionState

Track connection status:

enum ConnectionState {
  disconnected,
  connecting,
  connected,
  error,
}

// Extensions
state.isConnected;    // bool
state.isConnecting;   // bool
state.displayName;    // "Connected", "Connecting...", etc.

Platform Support

Feature	Android	iOS	Windows	macOS	Linux
Bluetooth	✅	✅	❌	❌	❌
USB	✅	❌	✅	❌	❌
Network	✅	✅	✅	✅	✅

Permissions

Android

Add to AndroidManifest.xml:

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

iOS

Add to Info.plist:

<key>NSBluetoothAlwaysUsageDescription</key>
<string>This app needs Bluetooth to connect to printers</string>
<key>NSBluetoothPeripheralUsageDescription</key>
<string>This app needs Bluetooth to connect to printers</string>

Example

See the example directory for a complete demo app.

License

MIT