Added PrinterNetworkManager. Updated examples.

example/discover_printers/.flutter-plugins-dependencies

+{"_info":"// This is a generated file; do not edit or check into version control.","dependencyGraph":[{"name":"flutter_bluetooth_basic","dependencies":[]},{"name":"wifi","dependencies":[]}]}
\ No newline at end of file

example/discover_printers/ios/Flutter/Flutter.podspec

+#
+# NOTE: This podspec is NOT to be published. It is only used as a local source!
+#
+
+Pod::Spec.new do |s|
+  s.name             = 'Flutter'
+  s.version          = '1.0.0'
+  s.summary          = 'High-performance, high-fidelity mobile apps.'
+  s.description      = <<-DESC
+Flutter provides an easy and productive way to build and deploy high-performance mobile apps for Android and iOS.
+                       DESC
+  s.homepage         = 'https://flutter.io'
+  s.license          = { :type => 'MIT' }
+  s.author           = { 'Flutter Dev Team' => 'flutter-dev@googlegroups.com' }
+  s.source           = { :git => 'https://github.com/flutter/engine', :tag => s.version.to_s }
+  s.ios.deployment_target = '8.0'
+  s.vendored_frameworks = 'Flutter.framework'
+end

example/discover_printers/ios/Flutter/flutter_export_environment.sh

@@ -2,9 +2,10 @@
 # This is a generated file; do not edit or check into version control.
 export "FLUTTER_ROOT=/Users/andrey/Documents/flutter"
 export "FLUTTER_APPLICATION_PATH=/Users/andrey/Documents/Tablemi_v2/esc_pos_printer/example/discover_printers"
-export "FLUTTER_TARGET=lib/main.dart"
+export "FLUTTER_TARGET=/Users/andrey/Documents/Tablemi_v2/esc_pos_printer/example/discover_printers/lib/main.dart"
 export "FLUTTER_BUILD_DIR=build"
 export "SYMROOT=${SOURCE_ROOT}/../build/ios"
 export "FLUTTER_FRAMEWORK_DIR=/Users/andrey/Documents/flutter/bin/cache/artifacts/engine/ios"
 export "FLUTTER_BUILD_NAME=1.0.0"
 export "FLUTTER_BUILD_NUMBER=1"
+export "TRACK_WIDGET_CREATION=true"

example/discover_printers/ios/Podfile.lock

 PODS:
   - Flutter (1.0.0)
+  - flutter_bluetooth_basic (0.0.1):
+    - Flutter
   - wifi (0.0.1):
     - Flutter
 
 DEPENDENCIES:
   - Flutter (from `.symlinks/flutter/ios`)
+  - flutter_bluetooth_basic (from `.symlinks/plugins/flutter_bluetooth_basic/ios`)
   - wifi (from `.symlinks/plugins/wifi/ios`)
 
 EXTERNAL SOURCES:
   Flutter:
     :path: ".symlinks/flutter/ios"
+  flutter_bluetooth_basic:
+    :path: ".symlinks/plugins/flutter_bluetooth_basic/ios"
   wifi:
     :path: ".symlinks/plugins/wifi/ios"
 
 SPEC CHECKSUMS:
-  Flutter: 58dd7d1b27887414a370fcccb9e645c08ffd7a6a
+  Flutter: 0e3d915762c693b495b44d77113d4970485de6ec
+  flutter_bluetooth_basic: 0e4e27e22b50b3a25cc1d1e131953feb4af414f4
   wifi: d7d77c94109e36c4175d845f0a5964eadba71060
 
 PODFILE CHECKSUM: aff02bfeed411c636180d6812254b2daeea14d09
 
-COCOAPODS: 1.7.5
+COCOAPODS: 1.8.4

example/discover_printers/lib/main.dart

@@ -63,7 +63,7 @@ class _MyHomePageState extends State<MyHomePage> {
     }
     print('subnet:\t$subnet, port:\t$port');
 
-    final stream = NetworkAnalyzer.discover(subnet, port);
+    final stream = NetworkAnalyzer.discover2(subnet, port);
 
     stream.listen((NetworkAddress addr) {
       if (addr.exists) {
@@ -87,23 +87,26 @@ class _MyHomePageState extends State<MyHomePage> {
       });
   }
 
-  void testPrint(String printerIp, BuildContext ctx) {
-    Printer.connect(printerIp,
-            port: int.parse(portController.text), timeout: Duration(seconds: 5))
-        .then((printer) async {
-      printer.println('Normal text');
-      printer.println('Bold text', styles: PosStyles(bold: true));
-      printer.println('Reverse text', styles: PosStyles(reverse: true));
-      printer.println('Underlined text',
+  Future<Ticket> testTicket() async {
+    final Ticket ticket = Ticket(PaperSize.mm80);
+
+    ticket.text(
+        'Regular: aA bB cC dD eE fF gG hH iI jJ kK lL mM nN oO pP qQ rR sS tT uU vV wW xX yY zZ');
+    ticket.text('Special 1: àÀ èÈ éÉ ûÛ üÜ çÇ ôÔ',
+        styles: PosStyles(codeTable: PosCodeTable.westEur));
+    ticket.text('Special 2: blåbærgrød',
+        styles: PosStyles(codeTable: PosCodeTable.westEur));
+
+    ticket.text('Bold text', styles: PosStyles(bold: true));
+    ticket.text('Reverse text', styles: PosStyles(reverse: true));
+    ticket.text('Underlined text',
         styles: PosStyles(underline: true), linesAfter: 1);
-      printer.println('Align left',
-          styles: PosStyles(align: PosTextAlign.left));
-      printer.println('Align center',
-          styles: PosStyles(align: PosTextAlign.center));
-      printer.println('Align right',
+    ticket.text('Align left', styles: PosStyles(align: PosTextAlign.left));
+    ticket.text('Align center', styles: PosStyles(align: PosTextAlign.center));
+    ticket.text('Align right',
         styles: PosStyles(align: PosTextAlign.right), linesAfter: 1);
 
-      printer.printRow([
+    ticket.row([
       PosColumn(
         text: 'col3',
         width: 3,
@@ -121,7 +124,7 @@ class _MyHomePageState extends State<MyHomePage> {
       ),
     ]);
 
-      printer.println('Text size 200%',
+    ticket.text('Text size 200%',
         styles: PosStyles(
           height: PosTextSize.size2,
           width: PosTextSize.size2,
@@ -131,20 +134,36 @@ class _MyHomePageState extends State<MyHomePage> {
     final ByteData data = await rootBundle.load('assets/logo.png');
     final Uint8List bytes = data.buffer.asUint8List();
     final Image image = decodeImage(bytes);
-      printer.printImage(image);
+    ticket.image(image);
+    // Print image using an alternative (obsolette) command
+    // ticket.imageRaster(image);
 
-      printer.cut();
-      printer.disconnect();
+    // Print barcode
+    final List<int> barData = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 4];
+    ticket.barcode(Barcode.upcA(barData));
 
-      final snackBar =
-          SnackBar(content: Text('Success', textAlign: TextAlign.center));
-      Scaffold.of(ctx).showSnackBar(snackBar);
-    }).catchError((dynamic e) {
-      print('exception');
-      final snackBar =
-          SnackBar(content: Text('Fail', textAlign: TextAlign.center));
+    // Print mixed (chinese + latin) text. Only for printers supporting Kanji mode
+    // ticket.text(
+    //   'hello ! 中文字 # world @ éphémère &',
+    //   styles: PosStyles(codeTable: PosCodeTable.westEur),
+    //   containsChinese: true,
+    // );
+
+    ticket.feed(2);
+
+    ticket.cut();
+    return ticket;
+  }
+
+  void testPrint(String printerIp, BuildContext ctx) async {
+    final PrinterNetworkManager printerManager = PrinterNetworkManager();
+    printerManager.selectPrinter(printerIp, port: 9100);
+
+    final PosPrintResult res =
+        await printerManager.printTicket(await testTicket());
+    final snackBar = SnackBar(
+        content: Text(PosPrintResult.msg(res), textAlign: TextAlign.center));
     Scaffold.of(ctx).showSnackBar(snackBar);
-    });
   }
 
   @override

example/discover_printers/pubspec.yaml

@@ -20,7 +20,7 @@ dependencies:
   flutter:
     sdk: flutter
   wifi: ^0.1.5
-  ping_discover_network: ^0.1.2
+  ping_discover_network: ^0.2.0+1
   image: ^2.1.4
   esc_pos_printer:
     path: ../../

example/example.dart

 import 'dart:io';
-import 'package:esc_pos_printer/esc_pos_printer.dart';
+import 'dart:typed_data';
+import 'package:flutter/services.dart';
 import 'package:image/image.dart';
+import 'package:esc_pos_printer/esc_pos_printer.dart';
 
-void main() {
-  // To discover existing printers in your subnet, consider using
+void main() async {
+  final PrinterNetworkManager printerManager = PrinterNetworkManager();
+  // To discover network printers in your subnet, consider using
   // ping_discover_network package (https://pub.dev/packages/ping_discover_network).
-  // Note that most of ESC/POS printers by default listen on port 9100.
-  Printer.connect('192.168.0.123', port: 9100).then((printer) {
-    printer.println(
+  // Note that most of ESC/POS printers are available on port 9100 by default.
+  printerManager.selectPrinter('192.168.0.123', port: 9100);
+
+  final PosPrintResult res =
+      await printerManager.printTicket(await testTicket());
+  print('Print result: ${PosPrintResult.msg(res)}');
+}
+
+Future<Ticket> testTicket() async {
+  final Ticket ticket = Ticket(PaperSize.mm80);
+
+  ticket.text(
       'Regular: aA bB cC dD eE fF gG hH iI jJ kK lL mM nN oO pP qQ rR sS tT uU vV wW xX yY zZ');
-    printer.println('Special 1: àÀ èÈ éÉ ûÛ üÜ çÇ ôÔ',
+  ticket.text('Special 1: àÀ èÈ éÉ ûÛ üÜ çÇ ôÔ',
       styles: PosStyles(codeTable: PosCodeTable.westEur));
-    printer.println('Special 2: blåbærgrød',
+  ticket.text('Special 2: blåbærgrød',
       styles: PosStyles(codeTable: PosCodeTable.westEur));
 
-    printer.println('Bold text', styles: PosStyles(bold: true));
-    printer.println('Reverse text', styles: PosStyles(reverse: true));
-    printer.println('Underlined text',
+  ticket.text('Bold text', styles: PosStyles(bold: true));
+  ticket.text('Reverse text', styles: PosStyles(reverse: true));
+  ticket.text('Underlined text',
       styles: PosStyles(underline: true), linesAfter: 1);
-    printer.println('Align left', styles: PosStyles(align: PosTextAlign.left));
-    printer.println('Align center',
-        styles: PosStyles(align: PosTextAlign.center));
-    printer.println('Align right',
+  ticket.text('Align left', styles: PosStyles(align: PosTextAlign.left));
+  ticket.text('Align center', styles: PosStyles(align: PosTextAlign.center));
+  ticket.text('Align right',
       styles: PosStyles(align: PosTextAlign.right), linesAfter: 1);
-    printer.printRow([
+
+  ticket.row([
     PosColumn(
       text: 'col3',
       width: 3,
@@ -40,30 +52,34 @@ void main() {
       styles: PosStyles(align: PosTextAlign.center, underline: true),
     ),
   ]);
-    printer.println('Text size 200%',
+
+  ticket.text('Text size 200%',
       styles: PosStyles(
         height: PosTextSize.size2,
         width: PosTextSize.size2,
       ));
 
   // Print image
-    const String filename = './logo.png';
-    final Image image = decodeImage(File(filename).readAsBytesSync());
-    printer.printImage(image);
+  final ByteData data = await rootBundle.load('assets/logo.png');
+  final Uint8List bytes = data.buffer.asUint8List();
+  final Image image = decodeImage(bytes);
+  ticket.image(image);
   // Print image using an alternative (obsolette) command
-    // printer.printImageRaster(image);
+  // ticket.imageRaster(image);
 
   // Print barcode
   final List<int> barData = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 4];
-    printer.printBarcode(Barcode.upcA(barData));
+  ticket.barcode(Barcode.upcA(barData));
 
   // Print mixed (chinese + latin) text. Only for printers supporting Kanji mode
-    // printer.println(
+  // ticket.text(
   //   'hello ! 中文字 # world @ éphémère &',
   //   styles: PosStyles(codeTable: PosCodeTable.westEur),
+  //   containsChinese: true,
   // );
 
-    printer.cut();
-    printer.disconnect();
-  });
+  ticket.feed(2);
+
+  ticket.cut();
+  return ticket;
 }

lib/esc_pos_printer.dart

@@ -11,6 +11,6 @@ export './src/barcode.dart';
 export './src/enums.dart';
 export './src/pos_column.dart';
 export './src/pos_styles.dart';
-export './src/printer.dart';
 export './src/printer_bluetooth_manager.dart';
+export './src/printer_network_manager.dart';
 export './src/ticket.dart';

lib/src/enums.dart

@@ -10,6 +10,29 @@ enum PosTextAlign { left, center, right }
 enum PosCutMode { full, partial }
 enum PosFontType { fontA, fontB }
 
+class PosPrintResult {
+  const PosPrintResult._internal(this.value);
+  final int value;
+  static const success = PosPrintResult._internal(1);
+  static const timeout = PosPrintResult._internal(2);
+  static const printerNotSelected = PosPrintResult._internal(3);
+  static const ticketEmpty = PosPrintResult._internal(4);
+
+  static String msg(PosPrintResult val) {
+    if (val == PosPrintResult.success) {
+      return 'Success';
+    } else if (val == PosPrintResult.timeout) {
+      return 'Error. Printer connection timeout';
+    } else if (val == PosPrintResult.printerNotSelected) {
+      return 'Error. Printer not selected';
+    } else if (val == PosPrintResult.ticketEmpty) {
+      return 'Error. Ticket is empty';
+    } else {
+      return 'Unknown error';
+    }
+  }
+}
+
 class PosTextSize {
   const PosTextSize._internal(this.value);
   final int value;

lib/src/printer_bluetooth_manager.dart

@@ -94,7 +94,6 @@ class PrinterBluetoothManager {
     _bluetoothManager.state.listen((state) async {
       switch (state) {
         case BluetoothManager.CONNECTED:
-          // print('********************* CONNECTED');
           // To avoid double call
           if (!_isConnected) {
             await _bluetoothManager.writeData(bytes);
@@ -102,14 +101,12 @@ class PrinterBluetoothManager {
           }
           // TODO sending disconnect signal should be event-based
           _runDelayed(3).then((dynamic v) async {
-            // print('DISCONNECTING......');
             await _bluetoothManager.disconnect();
             _isPrinting = false;
           });
           _isConnected = true;
           break;
         case BluetoothManager.DISCONNECTED:
-          // print('********************* DISCONNECTED');
           _isConnected = false;
           break;
         default:
@@ -127,7 +124,7 @@ class PrinterBluetoothManager {
   }
 
   Future<void> printTicket(Ticket ticket) async {
-    if (ticket.bytes.isNotEmpty) {
+    if (ticket != null && ticket.bytes.isNotEmpty) {
       final Future<void> res = writeBytes(ticket.bytes);
       return res;
     } else {

lib/src/printer_network_manager.dart

+/*
+ * esc_pos_printer
+ * Created by Andrey Ushakov
+ * 
+ * Copyright (c) 2019-2020. All rights reserved.
+ * See LICENSE for distribution and usage details.
+ */
+
+import 'dart:io';
+import './enums.dart';
+import './ticket.dart';
+
+/// Printer Network Manager
+class PrinterNetworkManager {
+  String _host;
+  int _port;
+  Duration _timeout;
+
+  /// Select a network printer
+  ///
+  /// [timeout] is used to specify the maximum allowed time to wait
+  /// for a connection to be established.
+  void selectPrinter(
+    String host, {
+    int port = 9100,
+    Duration timeout = const Duration(seconds: 5),
+  }) {
+    _host = host;
+    _port = port;
+    _timeout = timeout;
+  }
+
+  Future<PosPrintResult> printTicket(Ticket ticket) {
+    if (_host == null || _port == null) {
+      return Future<PosPrintResult>.value(PosPrintResult.printerNotSelected);
+    } else if (ticket == null || ticket.bytes.isEmpty) {
+      return Future<PosPrintResult>.value(PosPrintResult.ticketEmpty);
+    }
+
+    return Socket.connect(_host, _port, timeout: _timeout)
+        .then((Socket socket) {
+      socket.add(ticket.bytes);
+      socket.destroy();
+      return Future<PosPrintResult>.value(PosPrintResult.success);
+    }).catchError((dynamic e) {
+      return Future<PosPrintResult>.value(PosPrintResult.timeout);
+    });
+  }
+}