added Flutter example for image printing

example/discover_printers/lib/main.dart

-import 'package:flutter/material.dart';
+import 'dart:typed_data';
+import 'package:flutter/material.dart' hide Image;
 import 'package:esc_pos_printer/esc_pos_printer.dart';
+import 'package:flutter/services.dart';
 import 'package:ping_discover_network/ping_discover_network.dart';
+import 'package:image/image.dart';
 import 'package:wifi/wifi.dart';
 
 void main() => runApp(MyApp());
@@ -87,7 +90,7 @@ 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) {
+        .then((printer) async {
       printer.println('Normal text');
       printer.println('Bold text', styles: PosStyles(bold: true));
       printer.println('Reverse text', styles: PosStyles(reverse: true));
@@ -124,6 +127,12 @@ class _MyHomePageState extends State<MyHomePage> {
             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);
+      printer.printImage(image);
+
       printer.cut();
       printer.disconnect();
 

example/discover_printers/pubspec.yaml

@@ -21,6 +21,7 @@ dependencies:
     sdk: flutter
   wifi: ^0.1.5
   ping_discover_network: ^0.1.2
+  image: ^2.1.4
   esc_pos_printer:
     path: ../../
 
@@ -44,10 +45,8 @@ flutter:
   # the material Icons class.
   uses-material-design: true
 
-  # To add assets to your application, add an assets section, like this:
-  # assets:
-  #  - images/a_dot_burr.jpeg
-  #  - images/a_dot_ham.jpeg
+  assets:
+    - assets/logo.png
 
   # An image asset can refer to one or more resolution-specific "variants", see
   # https://flutter.dev/assets-and-images/#resolution-aware.