Flutter打印功能插件flutter_star_prnt_plus的使用
Flutter打印功能插件 flutter_star_prnt_plus 的使用
flutter_star_prnt_plus 是一个用于与 Star Micronics 打印机进行交互的 Flutter 插件。本文将详细介绍如何使用这个插件，包括安装、配置和示例代码。
1. 安装
首先，在你的 pubspec.yaml 文件中添加依赖：
dependencies:
flutter_star_prnt_plus: ^latest_version
然后运行以下命令来获取包：
flutter pub get
2. 更新注意事项
如果你之前使用的版本低于 1.0.4，并且在更新后遇到问题，请运行以下命令清理缓存：
rm -rf ios/Pods && rm ios/Podfile.lock && flutter clean
3. 获取打印机列表
你可以通过调用 portDiscovery 方法来查找可用的打印机。以下是一个简单的示例：
import 'package:flutter_star_prnt/flutter_star_prnt.dart';
// 查找所有类型的打印机
List<PortInfo> list = await StarPrnt.portDiscovery(StarPortType.All);
list.forEach((port) async {
// 检查打印机状态
await StarPrnt.checkStatus(
portName: port.portName,
emulation: 'StarGraphic',
);
});
4. 发送打印命令
一旦你找到了打印机并检查了其状态，就可以发送打印命令了。以下是一个完整的示例：
PrintCommands commands = PrintCommands();
commands.push({
'appendBitmapText': "Hello World"
});
commands.push({
'appendCutPaper': "FullCutWithFeed"
});
await StarPrnt.print(
portName: port.portName,
emulation: 'StarGraphic',
printCommands: commands,
);
5. Android 配置
为了确保插件能够在 Android 设备上正常工作，你需要在 AndroidManifest.xml 文件中添加以下权限：
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.BLUETOOTH"/>
6. iOS 配置
对于 iOS 设备，你需要在 Info.plist 文件中添加以下内容以支持蓝牙打印机：
<key>UISupportedExternalAccessoryProtocols</key>
<array>
<string>jp.star-m.starpro</string>
</array>
7. 示例应用
以下是一个完整的 Flutter 应用示例，展示了如何使用 flutter_star_prnt_plus 插件进行打印操作：
示例代码
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter_star_prnt_plus/flutter_star_prnt.dart';
import 'dart:ui' as ui;
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
[@override](/user/override)
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
GlobalKey _globalKey = new GlobalKey();
bool isLoading = false;
Future<Uint8List> _capturePng() async {
try {
RenderRepaintBoundary? boundary = _globalKey.currentContext!
.findRenderObject() as RenderRepaintBoundary;
ui.Image image = await boundary.toImage(pixelRatio: 3.0);
ByteData? byteData =
await image.toByteData(format: ui.ImageByteFormat.png);
final pngBytes = byteData!.buffer.asUint8List();
return pngBytes;
} catch (e) {
print(e);
return Uint8List(0);
}
}
String emulationFor(String modelName) {
String emulation = 'StarGraphic';
if (modelName.isNotEmpty) {
final em = StarMicronicsUtilities.detectEmulation(modelName: modelName);
emulation = em?.emulation ?? 'StarGraphic';
}
return emulation;
}
[@override](/user/override)
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(title: const Text('Plugin example app')),
body: Column(
children: <Widget>[
TextButton(
onPressed: () async {
List<PortInfo> list = await StarPrnt.portDiscovery(StarPortType.All);
print(list);
list.forEach((port) async {
if (port.portName != null && port.portName!.isNotEmpty) {
print(await StarPrnt.getStatus(
portName: port.portName!,
emulation: emulationFor(port.modelName!),
));
PrintCommands commands = PrintCommands();
String raster = " Star Clothing Boutique\n" +
" 123 Star Road\n" +
" City, State 12345\n" +
"\n" +
"Date:MM/DD/YYYY Time:HH:MM PM\n" +
"--------------------------------------\n" +
"SALE\n" +
"SKU Description Total\n" +
"300678566 PLAIN T-SHIRT 10.99\n" +
"300692003 BLACK DENIM 29.99\n" +
"300651148 BLUE DENIM 29.99\n" +
"300642980 STRIPED DRESS 49.99\n" +
"30063847 BLACK BOOTS 35.99\n" +
"\n" +
"Subtotal 156.95\n" +
"Tax 0.00\n" +
"--------------------------------------\n" +
"Total 156.95\n" +
"--------------------------------------\n" +
"\n" +
"Charge\n" +
"156.95\n" +
"Visa XXXX-XXXX-XXXX-0123\n" +
"Refunds and Exchanges\n" +
"Within 30 days with receipt\n" +
"And tags attached\n";
commands.appendBitmapText(text: raster);
print(await StarPrnt.sendCommands(
portName: port.portName!,
emulation: emulationFor(port.modelName!),
printCommands: commands));
}
});
},
child: Text('Print from text'),
),
TextButton(
onPressed: () async {
List<PortInfo> list = await StarPrnt.portDiscovery(StarPortType.All);
print(list);
list.forEach((port) async {
if (port.portName != null && port.portName!.isNotEmpty) {
print(await StarPrnt.getStatus(
portName: port.portName!,
emulation: emulationFor(port.modelName!),
));
PrintCommands commands = PrintCommands();
commands.appendBitmap(
path: 'https://c8.alamy.com/comp/MPCNP1/camera-logo-design-photograph-logo-vector-icons-MPCNP1.jpg');
print(await StarPrnt.sendCommands(
portName: port.portName!,
emulation: emulationFor(port.modelName!),
printCommands: commands));
}
});
setState(() {
isLoading = false;
});
},
child: Text('Print from URL'),
),
SizedBox(
width: 576, // 3'' only
child: RepaintBoundary(
key: _globalKey,
child: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.center,
children: [
Text('This is a text to print as image, for 3\''),
],
),
),
),
TextButton(
onPressed: () async {
final img = await _capturePng();
setState(() {
isLoading = true;
});
List<PortInfo> list = await StarPrnt.portDiscovery(StarPortType.All);
print(list);
list.forEach((port) async {
if (port.portName != null && port.portName!.isNotEmpty) {
print(await StarPrnt.getStatus(
portName: port.portName!,
emulation: emulationFor(port.modelName!),
));
PrintCommands commands = PrintCommands();
commands.appendBitmapByte(
byteData: img,
diffusion: true,
bothScale: true,
alignment: StarAlignmentPosition.Left,
);
print(await StarPrnt.sendCommands(
portName: port.portName!,
emulation: emulationFor(port.modelName!),
printCommands: commands));
}
});
setState(() {
isLoading = false;
});
},
child: Text('Print from generated image'),
),
],
),
),
);
}
}
更多关于Flutter打印功能插件flutter_star_prnt_plus的使用的实战教程也可以访问 https://www.itying.com/category-92-b0.html
1 回复
更多关于Flutter打印功能插件flutter_star_prnt_plus的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
当然，以下是如何在Flutter项目中使用flutter_star_prnt_plus插件来实现打印功能的示例代码。这个插件通常用于与Star Micronics打印机进行交互。
首先，你需要在你的Flutter项目中添加flutter_star_prnt_plus依赖。在你的pubspec.yaml文件中添加以下依赖：
dependencies:
flutter:
sdk: flutter
flutter_star_prnt_plus: ^x.y.z # 请替换为最新版本号
然后，运行flutter pub get来获取依赖。
接下来，你需要在你的Flutter应用中初始化并使用这个插件。以下是一个简单的示例，展示了如何使用这个插件来发送打印命令：
import 'package:flutter/material.dart';
import 'package:flutter_star_prnt_plus/flutter_star_prnt_plus.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: Text('Flutter Star Print Plus Example'),
),
body: Center(
child: PrintButton(),
),
),
);
}
}
class PrintButton extends StatefulWidget {
@override
_PrintButtonState createState() => _PrintButtonState();
}
class _PrintButtonState extends State<PrintButton> {
String printerName = 'StarTSP650II'; // 请根据你的打印机型号修改
String printerAddress = '00:1A:2B:3C:4D:5E'; // 请根据你的打印机蓝牙地址修改
@override
Widget build(BuildContext context) {
return ElevatedButton(
onPressed: () async {
// 初始化打印机
await FlutterStarPrntPlus.instance.initBluetoothPrinter(printerAddress, printerName);
// 准备打印内容
String textToPrint = "Hello, Flutter!\nThis is a test print.\n";
List<int> data = utf8.encode(textToPrint);
// 发送打印命令
try {
await FlutterStarPrntPlus.instance.printText(data);
ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Print successful')));
} catch (e) {
ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Print failed: ${e.message}')));
}
},
child: Text('Print'),
);
}
}
在这个示例中，我们创建了一个简单的Flutter应用，其中包含一个按钮。当用户点击按钮时，应用会尝试初始化蓝牙打印机，然后发送一个简单的打印任务。
请注意以下几点：
- 你需要确保你的打印机蓝牙地址和型号正确。
utf8.encode(textToPrint)用于将字符串转换为字节数组，因为大多数打印命令需要以字节数组的形式发送。- 这里的
FlutterStarPrntPlus.instance.printText(data)是一个示例方法，具体方法可能会根据插件的版本和打印机的型号有所不同。请查阅最新的插件文档以获取准确的方法调用和参数。
在实际应用中，你可能还需要处理更多的错误情况和用户交互，例如选择打印机、配置打印设置等。确保你阅读并理解flutter_star_prnt_plus插件的文档，以充分利用其功能。
