theme_extensions_builder

📖 Full documentation: packages/theme_extensions_builder/README.md

theme_extensions_builder is a powerful code generator for Flutter's ThemeExtension classes. It eliminates boilerplate code by automatically generating copyWith, lerp, ==, and hashCode methods, along with convenient BuildContext extensions for easy theme access.

🎯 Quick Links

• 📚 Full Documentation
• 🎨 Example Project
• 📦 pub.dev Package
• 🐛 Report Issues

📦 Installation

Add the packages to your project:

flutter pub add theme_extensions_builder_annotation
flutter pub add --dev theme_extensions_builder
flutter pub add --dev build_runner

Or add to pubspec.yaml:

dependencies:
  theme_extensions_builder_annotation: ^7.0.0

dev_dependencies:
  build_runner: ^2.10.4
  theme_extensions_builder: ^7.0.0

🚀 Quick Start

Using @ThemeExtensions

For classes extending ThemeExtension:

import 'package:flutter/material.dart';
import 'package:theme_extensions_builder_annotation/theme_extensions_builder_annotation.dart';

part 'app_theme.g.theme.dart';

@ThemeExtensions()
class AppTheme extends ThemeExtension<AppTheme> with _$AppThemeMixin {
  const AppTheme({
    required this.primaryColor,
    required this.spacing,
  });

  final Color primaryColor;
  final double spacing;
}

Generate code:

dart run build_runner build

Use in your app:

Widget build(BuildContext context) {
  final theme = context.appTheme;
  
  return Container(
    padding: EdgeInsets.all(theme.spacing),
    color: theme.primaryColor,
  );
}

Using @ThemeGen

For standalone theme data classes:

@ThemeGen()
class ButtonThemeData with _$ButtonThemeData {
  const ButtonThemeData({
    required this.backgroundColor,
    this.borderRadius = 8.0,
  });

  final Color backgroundColor;
  final double borderRadius;

  static ButtonThemeData? lerp(ButtonThemeData? a, ButtonThemeData? b, double t) =>
      _$ButtonThemeData.lerp(a, b, t);
}

📋 Choose Your Annotation

@ThemeExtensions (Recommended)

For classes extending Flutter's ThemeExtension - ideal for most use cases.

Perfect for:

• Full Flutter theme integration
• Automatic theme switching with lerp animations
• Easy access via BuildContext (e.g., context.appTheme)

Generates:

• Complete ThemeExtension implementation with copyWith and lerp
• BuildContext extension for convenient access
• Equality operators and hashCode

@ThemeGen

For standalone theme data classes without ThemeExtension inheritance.

Perfect for:

• Custom theme systems outside standard Flutter themes
• Maximum control over class structure
• Nested theme data objects

Generates:

• copyWith and merge methods
• Static lerp method
• Equality operators and hashCode

---

📖 Example

Check out the example project for a comprehensive Flutter app with:

• 5 Theme Extensions: App, Button, Card, Typography, and Spacing themes
• Theme Switching: Seamless light/dark mode transitions
• Custom Components: Buttons, cards, and typography showcases
• Best Practices: Real-world organization patterns

📄 License

MIT License - see the LICENSE file for details.