NyxPrinter Flutter Plugin #

The NyxPrinter package is a Flutter plugin that allows you to interact with printers, enabling functionalities such as printing text, barcodes, QR codes, and images. It leverages platform-specific code to communicate with the printer and perform various tasks.

Features #

• Print Text: Allows printing formatted text.
• Print Barcode: Enables printing of barcodes with customizable dimensions.
• Print QR Code: Enables printing of QR codes with customizable dimensions.
• Print Image: Allows printing PNG images.

Installation #

To use NyxPrinter in your Flutter project, add the following dependency to your pubspec.yaml file:

dependencies:
  nyx_printer: ^latest_version

Then, run the following command in your terminal to install the package:

flutter pub get

Importing the Package #

In your Dart file, import the necessary classes:

import 'package:nyx_printer/nyx_printer.dart';

Usage #

Below is an overview of how to use the NyxPrinter package:

1. Get Printer Version #

Use the getVersion method to retrieve the printer's version number. A successful result will return 0.

int? version = await NyxPrinter().getVersion();

2. Print Text #

To print text with specific formatting, use the printText method. You can optionally provide a NyxTextFormat object to define the text style, alignment, size, and more.

int? result = await NyxPrinter().printText(
  "Hello, World!", 
  textFormat: NyxTextFormat(
    textSize: 20, 
    style: NyxFontStyle.bold, 
    align: NyxAlign.center
  )
);

3. Print Barcode #

To print a barcode, use the printBarcode method. You can set the barcode's width and height.

int? result = await NyxPrinter().printBarcode(
  "1234567890", 
  width: 400, 
  height: 200
);

4. Print QR Code #

To print a QR code, use the printQrCode method. Like the barcode, you can adjust the width and height of the QR code.

int? result = await NyxPrinter().printQrCode(
  "https://flutter.cn", 
  width: 300, 
  height: 300
);

5. Print Image #

To print an image, convert your image to a Uint8List (PNG format), and pass it to the printImage method.

Uint8List imageBytes = await getImageBytes();  // Retrieve your PNG image as bytes
int? result = await NyxPrinter().printImage(imageBytes);

NyxTextFormat #

The NyxTextFormat class provides options for formatting text that is printed.

Properties: #

• textSize: Defines the font size (default is 24).
• underline: Specifies if the text should be underlined (default is false).
• textScaleX: Horizontal text scaling (default is 1.0).
• textScaleY: Vertical text scaling (default is 1.0).
• letterSpacing: Defines the spacing between letters (default is 0).
• lineSpacing: Defines the spacing between lines (default is 0).
• topPadding: Padding at the top (default is 0).
• leftPadding: Padding on the left (default is 0).
• align: Text alignment, can be left, center, or right (default is left).
• style: Font style, can be normal, bold, italic, or boldItalic (default is normal).
• font: Font family, can be defaultFont, defaultBold, sansSerif, serif, or monospace (default is defaultFont).

Example: #

NyxTextFormat(
  textSize: 30, 
  underline: true, 
  textScaleX: 1.5, 
  textScaleY: 1.5, 
  align: NyxAlign.center
);

Methods: #

The NyxTextFormat class provides the toMap method to convert the formatting options into a Map<String, dynamic>, which can be passed to platform-specific code.

Map<String, dynamic> formatMap = textFormat.toMap();

Enumerations #

NyxFontStyle #

Defines the style of the font:

• normal: Regular text.
• bold: Bold text.
• italic: Italic text.
• boldItalic: Bold and italic text.

NyxFont #

Defines the font family:

• defaultFont: The default font.
• defaultBold: Bold default font.
• sansSerif: Sans-serif font.
• serif: Serif font.
• monospace: Monospace font.

NyxAlign #

Defines text alignment:

• left: Left-aligned text.
• center: Center-aligned text.
• right: Right-aligned text.

Error Handling #

If any operation fails, the Future<int?> will return a non-zero error code. Ensure you handle errors appropriately.

Example Error Handling: #

int? result = await NyxPrinter().printText("Sample Text");
if (result != 0) {
  print("Failed to print text, error code: $result");
} else {
  print("Text printed successfully");
}

Contribution #

Feel free to fork the repository, submit issues, or pull requests. Contributions are welcome!

License #

This package is open-source and available under the MIT License.

Based on https://github.com/yyzz2333/NyxPrinterClient