Chunked Widget to Image Plugin

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A powerful Flutter plugin that converts Flutter widgets to high-quality image files. Using advanced chunking technology to break through platform texture size limitations, supports exporting ultra-large images to PNG or JPEG format.

✨ Features

• 🎨 Universal Widget Conversion: Convert any Flutter Widget to PNG or JPEG format image files
• 🖼️ Ultra-Large Image Support: Export images of any size, breaking through platform texture limitations (16384px+)
• 🚀 Off-Screen Rendering: Export widgets without adding them to the widget tree
• 📜 Long Content Export: Automatic pagination export for long lists and scrollable content
• ⚡ High Performance: Uses native libraries (libpng, libjpeg-turbo) for optimal performance
• 🌐 Multi-Platform Support: Android, iOS, macOS, Windows, Linux, and HarmonyOS

📦 Installation

Add this to your pubspec.yaml:

dependencies:
  chunked_widget_to_image: ^2.0.0

Then run:

flutter pub get

🎯 Quick Start

Basic Usage

import 'package:chunked_widget_to_image/chunked_widget_to_image.dart';

// Create controller
final controller = WidgetToImageController();

// Wrap your widget with WidgetToImage
WidgetToImage(
  controller: controller,
  child: YourWidget(), // The widget you want to convert
),

// Export to image file
controller.toImageFile(
  outPath: '/path/to/output.png',
  pixelRatio: 1.0,
  format: ImageFormat.png,
  callback: (result, message) {
    if (result) {
      print('✓ Export successful: $message');
    } else {
      print('✗ Export failed: $message');
    }
  },
);

Off-Screen Export

Export widgets without displaying them on screen:

controller.toImageFileFromWidget(
  YourWidget(),
  outPath: '/path/to/output.jpg',
  pixelRatio: 1.0,
  format: ImageFormat.jpg,
  context: context, // Optional: inherit app theme
  targetSize: Size(800, 600), // Optional: specify target size
  delay: Duration(seconds: 1),
  callback: (result, message) {
    // Handle result
  },
);

Long Content Export

Perfect for exporting long lists or scrollable content:

controller.toImageFileFromLongWidget(
  YourLongListWidget(),
  outPath: '/path/to/output.png',
  pixelRatio: 1.0,
  format: ImageFormat.png,
  context: context,
  constraints: BoxConstraints(maxWidth: 800), // Optional: custom constraints
  callback: (result, message) {
    // Handle result
  },
);

📖 API Reference

WidgetToImageController

toImageFile()

Export widget from widget tree to image file.

Parameters:

• outPath (required): Output file path
• pixelRatio: Device pixel ratio (default: 1.0)
• format: Image format (png/jpeg)
• callback: Export result callback
• delay: Delay before capture (default: 20ms)

toImageFileFromWidget()

Export off-screen widget to image file.

Parameters:

• widget (required): Widget to export
• outPath (required): Output file path
• pixelRatio: Device pixel ratio (default: 1.0)
• format: Image format (png/jpeg)
• context: BuildContext for theme inheritance (optional)
• targetSize: Target widget size (optional)
• delay: Delay before capture (default: 1s)
• callback: Export result callback

toImageFileFromLongWidget()

Export long/scrollable widget to image file.

Parameters:

• widget (required): Widget to export
• outPath (required): Output file path
• pixelRatio: Device pixel ratio (default: 1.0)
• format: Image format (png/jpeg)
• context: BuildContext for theme inheritance (optional)
• constraints: BoxConstraints for layout (optional)
• delay: Delay before capture (default: 1s)
• callback: Export result callback

WidgetToImage Widget

A convenience widget that wraps your content with a RepaintBoundary.

WidgetToImage(
  controller: controller,
  child: YourWidget(),
)

🌍 Supported Platforms

Platform	Status	Notes
Android	✅ Supported	Full support
iOS	✅ Supported	Full support
macOS	✅ Supported	ARM64 only (Apple Silicon)
Windows	✅ Supported	Full support
Linux	✅ Supported	FFI support available
HarmonyOS	✅ Supported	Full support

📝 Complete Example

See the example directory for a complete working example including:

• Basic widget export
• Off-screen rendering
• Long list export
• Performance timing
• Full-screen preview

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.