Flutter JSON Bean Factory

A powerful VSCode extension that automatically generates Dart model classes from JSON data for Flutter development. This extension is a VSCode port of the popular FlutterJsonBeanFactory IntelliJ plugin, bringing the same powerful functionality to VSCode users.

🤖 100% AI Generated: This entire project was developed using AI assistance, demonstrating the power of AI-driven development tools.

✨ Features

• 🚀 One-click JSON to Dart conversion - Generate complete Dart model classes from JSON
• 🔄 Automatic serialization - Generates fromJson() and toJson() methods
• 🛡️ Null safety support - Full support for Dart null safety
• 🎯 Smart type inference - Automatically detects and handles various data types
• 📝 Customizable generation - Extensive configuration options
• ⚡ Batch regeneration - Regenerate all models with Alt+J
• 🔧 Flexible file organization - Configurable output paths
• 🎨 Rich UI dialog - User-friendly JSON input interface

🚀 Quick Start

Installation

1. Open VSCode
2. Go to Extensions (Ctrl+Shift+X)
3. Search for "Flutter JSON Bean Factory"
4. Click Install

Basic Usage

1. Generate from JSON:

   • Use Ctrl+Alt+J (Windows/Linux) or Cmd+Alt+J (Mac)
   • Or right-click in Explorer → "Generate Dart Bean from JSON"
   • Paste your JSON and enter a class name
   • Click "Generate"

2. Regenerate existing models:

   • Use Alt+J to regenerate all models
   • Use Ctrl+Shift+J (Windows/Linux) or Cmd+Shift+J (Mac) to regenerate current file

📋 Example

Input JSON:

{
  "id": 1,
  "name": "John Doe",
  "email": "john@example.com",
  "is_active": true,
  "profile": {
    "age": 30,
    "avatar_url": "https://example.com/avatar.jpg"
  },
  "tags": ["developer", "flutter"]
}

Generated Dart Code:

user.dart:

import 'dart:convert';
import 'package:json_annotation/json_annotation.dart';
import 'package:your_project/generated/json/base/json_field.dart';
import 'package:your_project/generated/json/user.g.dart';

part 'user.g.dart';

@JsonSerializable()
class User {
  late int id;
  late String name;
  late String email;
  @JSONField(name: 'is_active')
  late bool isActive;
  late UserProfile profile;
  late List<String> tags;

  User();

  factory User.fromJson(Map<String, dynamic> json) => $UserFromJson(json);
  Map<String, dynamic> toJson() => $UserToJson(this);

  @override
  String toString() {
    return jsonEncode(this);
  }
}

@JsonSerializable()
class UserProfile {
  late int age;
  @JSONField(name: 'avatar_url')
  late String avatarUrl;

  UserProfile();

  factory UserProfile.fromJson(Map<String, dynamic> json) => $UserProfileFromJson(json);
  Map<String, dynamic> toJson() => $UserProfileToJson(this);

  @override
  String toString() {
    return jsonEncode(this);
  }
}

⌨️ Keyboard Shortcuts

⚙️ Configuration

Access settings via File > Preferences > Settings and search for "Flutter JSON Bean Factory":

File Paths

• Generated Path: Where helper files are saved (default: lib/generated/json)
• Entity Path: Where model files are saved (default: lib/models)
• Scan Path: Where to scan for existing models (default: lib)

Code Generation

• Null Safety: Generate null-safe code (default: true)
• Use JSON Annotation: Use json_annotation package (default: true)
• Class Name Prefix/Suffix: Add prefix/suffix to class names
• Generate toString: Include toString() method (default: true)
• Generate Equality: Include == operator and hashCode (default: false)

Nullable Options

• Open Nullable: Generate nullable fields with ? (default: false)
• Force Non-Nullable: Remove ? from all types (default: false)
• Add Null Checks: Add null checks in fromJson (default: true)

Default Values

• Set Default: Use default values for fields (default: true)
• String Default: Default for String fields (default: '')
• Int Default: Default for int fields (default: 0)
• Bool Default: Default for bool fields (default: false)
• List Default: Default for List fields (default: [])

📁 Project Structure

The extension generates files in the following structure:

lib/
├── models/                    # Entity/Model files
│   ├── user.dart
│   └── product.dart
└── generated/
    └── json/                  # Generated helper files
        ├── base/
        │   └── json_field.dart
        ├── json_convert_content.dart
        ├── user.g.dart
        └── product.g.dart

🔧 Commands

Available Commands

1. Generate Dart Bean from JSON

   • Command ID: flutter-json-bean-factory.generateFromJson
   • Opens interactive dialog for JSON input

2. Regenerate Dart Bean

   • Command ID: flutter-json-bean-factory.regenerateBean
   • Regenerates the currently open Dart model file

3. Regenerate All Dart Beans

   • Command ID: flutter-json-bean-factory.regenerateAllBeans
   • Scans and regenerates all existing Dart models

Context Menus

• Explorer Context Menu: Right-click on folders to generate models
• Editor Context Menu: Right-click in Dart files to regenerate models

🛠️ Requirements

• VSCode 1.74.0 or higher
• Flutter project with pubspec.yaml
• Dart language support

Required Dependencies

Add these to your pubspec.yaml:

dependencies:
  json_annotation: ^4.8.1

dev_dependencies:
  json_serializable: ^6.7.1
  build_runner: ^2.4.7

🔍 Advanced Usage

Working with Complex JSON

The extension handles complex nested structures, arrays, and various data types:

{
  "users": [
    {
      "id": 1,
      "profile": {
        "personal_info": {
          "first_name": "John",
          "last_name": "Doe"
        }
      }
    }
  ],
  "metadata": {
    "total_count": 100,
    "has_more": true
  }
}

Custom Field Mapping

Use @JSONField annotations for custom field mapping:

• Snake case JSON keys → Camel case Dart properties
• Automatic annotation generation for mismatched names

Batch Operations

• Alt+J: Regenerates ALL models in your project
• Preserves existing customizations in entity files
• Updates only the .g.dart files

🐛 Troubleshooting

Common Issues

1. "This command only works in Flutter projects"

   • Ensure your project has a pubspec.yaml file
   • Open the project root folder in VSCode

2. Generated files not found

   • Check your configuration paths
   • Ensure the target directories exist

3. Build errors after generation

   • Run flutter packages pub run build_runner build
   • Add required dependencies to pubspec.yaml

Build Runner Commands

After generating models, run:

# Generate .g.dart files
flutter packages pub run build_runner build

# Watch for changes
flutter packages pub run build_runner watch

# Clean and rebuild
flutter packages pub run build_runner build --delete-conflicting-outputs

🙏 Acknowledgments

This project is based on the excellent FlutterJsonBeanFactory IntelliJ plugin by the FlutterCandies team. We are grateful for their innovative work and open-source contribution to the Flutter community.

Original Project: FlutterJsonBeanFactory for IntelliJ IDEA Original Authors: FlutterCandies Team License: MIT

Special thanks to the FlutterCandies community for creating such a useful tool that inspired this VSCode adaptation.

🤖 AI Development

This entire VSCode extension was developed using 100% AI assistance, showcasing the capabilities of modern AI development tools. The project demonstrates how AI can effectively:

• Port functionality between different IDE platforms
• Understand and replicate complex code generation logic
• Maintain feature parity while adapting to different extension APIs
• Create comprehensive documentation and user interfaces

This serves as an example of AI-driven software development and the potential for AI to accelerate cross-platform tool development.

📄 License

MIT License - see the LICENSE file for details.

🔗 Links

• GitHub Repository - Source code and development
• VSCode Marketplace
• Original IntelliJ Plugin
• FlutterCandies Organization
• Report Issues