Using Ticket class. Print test ticket (bluetooth).

example/blue/lib/main.dart

+import 'dart:typed_data';
+import 'package:flutter/services.dart';
+import 'package:image/image.dart';
 import 'package:esc_pos_printer/esc_pos_printer.dart';
-import 'package:flutter/material.dart';
+import 'package:flutter/material.dart' hide Image;
 import 'package:oktoast/oktoast.dart';
 
 void main() => runApp(MyApp());
@@ -57,19 +60,70 @@ class _MyHomePageState extends State<MyHomePage> {
   void _testPrint(PrinterBluetooth printer) async {
     printerManager.selectPrinter(printer);
 
-    // printerManager.addText('left', styles: PosStyles(align: PosTextAlign.left));
-    // printerManager.addText('center',
-    //     styles: PosStyles(align: PosTextAlign.center));
-    // printerManager.addText('right',
-    //     styles: PosStyles(align: PosTextAlign.right), linesAfter: 3);
+    Ticket ticket = Ticket(PaperSize.mm58);
 
-    printerManager.addText(
+    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');
-    printerManager.addText('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));
-    printerManager.addEmptyLines(3);
+    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);
+    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);
+
+    ticket.row([
+      PosColumn(
+        text: 'col3',
+        width: 3,
+        styles: PosStyles(align: PosTextAlign.center, underline: true),
+      ),
+      PosColumn(
+        text: 'col6',
+        width: 6,
+        styles: PosStyles(align: PosTextAlign.center, underline: true),
+      ),
+      PosColumn(
+        text: 'col3',
+        width: 3,
+        styles: PosStyles(align: PosTextAlign.center, underline: true),
+      ),
+    ]);
+
+    ticket.text('Text size 200%',
+        styles: PosStyles(
+          height: PosTextSize.size2,
+          width: PosTextSize.size2,
+        ));
+
+    // Print 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
+    // ticket.imageRaster(image);
+
+    // Print barcode
+    final List<int> barData = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 4];
+    ticket.barcode(Barcode.upcA(barData));
+
+    // 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);
 
-    printerManager.printTicket().then((val) {
+    printerManager.printTicket(ticket).then((val) {
       showToast('Success!');
     }).catchError((dynamic e) {
       print('catched: ${e.toString()}');

example/blue/pubspec.yaml

@@ -10,6 +10,7 @@ dependencies:
     sdk: flutter
   cupertino_icons: ^0.1.2
   oktoast: ^2.3.0
+  image: ^2.1.4
   esc_pos_printer:
     path: ../../
 
@@ -19,3 +20,5 @@ dev_dependencies:
 
 flutter:
   uses-material-design: true
+  assets:
+    - assets/logo.png

lib/esc_pos_printer.dart

@@ -9,7 +9,7 @@ library esc_pos_printer;
 export './src/barcode.dart';
 export './src/enums.dart';
 export './src/pos_column.dart';
-export './src/pos_generator.dart';
 export './src/pos_styles.dart';
 export './src/printer.dart';
 export './src/printer_bluetooth_manager.dart';
+export './src/ticket.dart';

lib/src/enums.dart

@@ -26,6 +26,15 @@ class PosTextSize {
       16 * (width.value - 1) + (height.value - 1);
 }
 
+class PaperSize {
+  const PaperSize._internal(this.value);
+  final int value;
+  static const mm58 = PaperSize._internal(1);
+  static const mm80 = PaperSize._internal(2);
+
+  static int width(PaperSize size) => size == PaperSize.mm58 ? 350 : 512;
+}
+
 class PosBeepDuration {
   const PosBeepDuration._internal(this.value);
   final int value;

lib/src/pos_generator.dart

-import 'dart:convert';
-// import 'dart:io';
-import 'dart:typed_data';
-// import 'package:gbk_codec/gbk_codec.dart';
-// import 'package:hex/hex.dart';
-// import 'package:image/image.dart';
-// import 'barcode.dart';
-import 'commands.dart';
-import 'enums.dart';
-// import 'pos_column.dart';
-import 'pos_styles.dart';
-
-class PosGenerator {
-  static List<int> emptyLines(int n) {
-    if (n > 0) {
-      return latin1.encode(List.filled(n, '\n').join());
-    }
-    return [];
-  }
-
-  static List<int> text(
-    String text, {
-    PosStyles styles = const PosStyles(),
-    int linesAfter = 0,
-  }) {
-    List<int> bytes = [];
-
-    bytes += latin1.encode(styles.align == PosTextAlign.left
-        ? cAlignLeft
-        : (styles.align == PosTextAlign.center ? cAlignCenter : cAlignRight));
-
-    // Set local code table
-    if (styles.codeTable != null) {
-      bytes += Uint8List.fromList(
-        List.from(cCodeTable.codeUnits)..add(styles.codeTable.value),
-      );
-    }
-    bytes += latin1.encode(text + '\n');
-    bytes += emptyLines(linesAfter);
-
-    return bytes;
-  }
-}

lib/src/printer_bluetooth_manager.dart

@@ -41,7 +41,6 @@ class PrinterBluetoothManager {
   StreamSubscription _scanResultsSubscription;
   StreamSubscription _isScanningSubscription;
   PrinterBluetooth _selectedPrinter;
-  List<int> _printBuffer = [];
 
   final BehaviorSubject<bool> _isScanning = BehaviorSubject.seeded(false);
   Stream<bool> get isScanningStream => _isScanning.stream;
@@ -107,7 +106,7 @@ class PrinterBluetoothManager {
     _bluetoothManager.state.listen((state) async {
       switch (state) {
         case BluetoothManager.CONNECTED:
-          print('********************* CONNECTED');
+          // print('********************* CONNECTED');
           // To avoid double call
           if (!_isConnected) {
             await _bluetoothManager.writeData(bytes);
@@ -115,14 +114,14 @@ class PrinterBluetoothManager {
           }
           // TODO sending disconnect signal should be event-based
           _runDelayed(3).then((dynamic v) async {
-            print('DISCONNECTING......');
+            // print('DISCONNECTING......');
             await _bluetoothManager.disconnect();
             _isPrinting = false;
           });
           _isConnected = true;
           break;
         case BluetoothManager.DISCONNECTED:
-          print('********************* DISCONNECTED');
+          // print('********************* DISCONNECTED');
           _isConnected = false;
           break;
         default:
@@ -139,26 +138,12 @@ class PrinterBluetoothManager {
     });
   }
 
-  void addText(
-    String text, {
-    PosStyles styles = const PosStyles(),
-    int linesAfter = 0,
-  }) {
-    _printBuffer +=
-        PosGenerator.text(text, styles: styles, linesAfter: linesAfter);
-  }
-
-  void addEmptyLines(int n) {
-    _printBuffer += PosGenerator.emptyLines(n);
-  }
-
-  Future<void> printTicket() async {
-    if (_printBuffer.isNotEmpty) {
-      final Future<void> res = writeBytes(_printBuffer);
-      _printBuffer = [];
+  Future<void> printTicket(Ticket ticket) async {
+    if (ticket.bytes.isNotEmpty) {
+      final Future<void> res = writeBytes(ticket.bytes);
       return res;
     } else {
-      throw Exception('Print failed (print buffer is empty)');
+      throw Exception('Print failed (ticket is empty)');
     }
   }
 }