flutter_thermal_printer 0.0.15

Plugin for Flutter to print on thermal printers via ESC/POS commands.

example/lib/main.dart

// ignore_for_file: depend_on_referenced_packages

import 'dart:async';
import 'dart:developer';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_thermal_printer/flutter_thermal_printer.dart';
import 'package:flutter_thermal_printer/utils/printer.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final _flutterThermalPrinterPlugin = FlutterThermalPrinter.instance;

  List<Printer> printers = [];

  StreamSubscription<List<Printer>>? _devicesStreamSubscription;

  // Get Printer List
  void startScan() async {
    _devicesStreamSubscription?.cancel();
    await _flutterThermalPrinterPlugin.getPrinters();
    _devicesStreamSubscription = _flutterThermalPrinterPlugin.devicesStream
        .listen((List<Printer> event) {
      log(event.map((e) => e.name).toList().toString());
      setState(() {
        printers = event;
        printers.removeWhere((element) =>
            element.name == null ||
            element.name == '' ||
            !element.name!.toLowerCase().contains('print'));
      });
    });
  }

  @override
  void initState() {
    super.initState();
    _devicesStreamSubscription = _flutterThermalPrinterPlugin.devicesStream
        .listen((List<Printer> event) {
      log(event.map((e) => e.name).toList().toString());
      setState(() {
        printers = event;
        printers.removeWhere((element) =>
            element.name == null ||
            element.name == '' ||
            !element.name!.toLowerCase().contains('print'));
      });
    });
  }

  void getUsbDevices() async {
    await _flutterThermalPrinterPlugin.getUsbDevices();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Plugin example app'),
          systemOverlayStyle: const SystemUiOverlayStyle(
            statusBarColor: Colors.transparent,
          ),
        ),
        body: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            ElevatedButton(
              onPressed: () {
                // startScan();
                startScan();
              },
              child: const Text('Get Printers'),
            ),
            Expanded(
              child: ListView.builder(
                itemCount: printers.length,
                itemBuilder: (context, index) {
                  return StreamBuilder(
                      stream: printers[index].connectionState,
                      builder: (context, snapshot) {
                        return ListTile(
                          onTap: () async {
                            if (printers[index].isConnected ?? false) {
                              await _flutterThermalPrinterPlugin
                                  .disconnect(printers[index]);
                            } else {
                              final isConnected =
                                  await _flutterThermalPrinterPlugin
                                      .connect(printers[index]);
                              log("Devices: $isConnected");
                            }
                          },
                          title: Text(printers[index].name ?? 'No Name'),
                          subtitle: Text(
                            "Connected: ${printers[index].isConnected}"
                            " ${snapshot.data}",
                          ),
                          trailing: IconButton(
                            icon: const Icon(Icons.connect_without_contact),
                            onPressed: () async {
                              final profile = await CapabilityProfile.load();
                              final generator =
                                  Generator(PaperSize.mm80, profile);
                              List<int> bytes = [];
                              bytes += generator.text(
                                "Sunil Kumar",
                                styles: const PosStyles(
                                  bold: true,
                                  height: PosTextSize.size3,
                                  width: PosTextSize.size3,
                                ),
                              );
                              bytes += generator.cut();
                              await _flutterThermalPrinterPlugin.printData(
                                printers[index],
                                bytes,
                                longData: true,
                              );
                            },
                          ),
                        );
                      });
                },
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget receiptWidget() {
    return Container(
        padding: const EdgeInsets.all(8),
        color: Colors.white,
        width: 300,
        height: 300,
        child: const Center(
          child: Column(
            children: [
              Text(
                "FLUTTER THERMAL PRINTER",
                style: TextStyle(
                  fontSize: 20,
                  fontWeight: FontWeight.bold,
                  color: Colors.black,
                ),
              ),
              SizedBox(height: 10),
              Text(
                "Hello World",
                style: TextStyle(
                  fontSize: 16,
                  fontWeight: FontWeight.bold,
                  color: Colors.black,
                ),
              ),
              SizedBox(height: 10),
              Text(
                "This is a test receipt",
                style: TextStyle(
                  fontSize: 16,
                  fontWeight: FontWeight.bold,
                  color: Colors.black,
                ),
              ),
            ],
          ),
        ));
  }
}