chunked_widget_to_image - Dart API docs

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A Flutter plugin that converts Flutter widgets to image files with support for large images via chunking technology.

Features

Convert any Flutter Widget to PNG or JPEG format image files
Support exporting ultra-large sized images (breaking most platform texture limitations)
Off-screen rendering support without adding Widget to the Widget tree
Automatic pagination export function for long lists/long content
Pre-compiled static libraries for faster build times and consistent behavior
Uses native libraries (libpng, libjpeg-turbo) for high performance and quality on supported platforms (Android/iOS/macOS/Windows)
Linux platform is currently not supported

Installation

Add this to your pubspec.yaml:

dependencies:
  chunked_widget_to_image: ^latest

Then run:

flutter pub get

Platform Implementation

This plugin uses different implementations based on the platform:

Supported platforms (Android/iOS/macOS/Windows): Uses native libraries (libpng, libjpeg-turbo) for high performance and quality
Linux platform is currently not supported

The plugin now uses pre-compiled static libraries for image processing instead of build-time configuration options. This approach eliminates the need for build-time environment variables and provides faster build times.

Usage

Basic Usage

// Create controller
final controller = WidgetToImageController();

// Use in widget tree
WidgetToImage(
  controller: controller,
  child: YourWidget(), // The widget you want to convert to image
),

// Export to image file
controller.toImageFile(
  outPath: '/path/to/output.png',
  format: ImageFormat.png,
  callback: (result, message) {
    if (result) {
      print('Image exported successfully: $message');
    } else {
      print('Image export failed: $message');
    }
  },
);

Off-screen Rendering

// Export widget without adding it to the widget tree
controller.toImageFileFromWidget(
  YourWidget(),
  outPath: '/path/to/output.jpg',
  format: ImageFormat.jpg,
  callback: (result, message) {
    // Handle result
  },
);

Long Content Export

// Export long list or long content widget
controller.toImageFileFromLongWidget(
  YourLongWidget(),
  outPath: '/path/to/output.png',
  format: ImageFormat.png,
  callback: (result, message) {
    // Handle result
  },
);

Supported Platforms

Android
iOS
macOS
Windows

Building

The plugin now uses pre-compiled static libraries for image processing instead of building from source. This approach provides:

Faster build times
Consistent behavior across environments
Reduced build complexity

Supported platforms (Android/iOS/macOS/Windows) use native libraries (libpng, libjpeg-turbo) distributed as pre-compiled static libraries.

Windows platform uses native libraries (libpng, libjpeg-turbo) for high performance and quality. Linux platform is currently not supported.

macOS Architecture Support

The macOS platform now supports only ARM64 architecture (Apple Silicon). This change simplifies distribution and ensures optimal performance on modern macOS devices.

Error Handling

When a feature is disabled at compile time and a user attempts to use it:

Functions will return error code -1 indicating the feature is not available
No crashes or undefined behavior will occur

Contributing

Contributions are welcome! Feel free to submit issues and pull requests.

License

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

Chunked Widget to Image Plugin