reactive_orm 0.0.9

A reactive object-relationship state management layer for Flutter with fine-grained field reactivity.

reactive_orm

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⚠️ Note: reactive_orm stands for a Reactive Object–Relationship Model.
It is not a database ORM.
It is a lightweight, field-level state management solution for Flutter UI, inspired by ORM-style modeling of objects and relationships — fully in-memory and UI-focused.

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🎬 Demo

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✨ Core Philosophy

• Models are plain Dart objects
• State changes happen via normal field mutation
• UI reacts automatically, with optional field-specific reactivity
• No ChangeNotifier, providers, streams, or extra boilerplate
• Supports object-wise, field-wise, and nested reactivity
• ORM-inspired design:
  • Objects represent application state
  • Relationships define propagation (Many → One, Many ↔ Many)
  • Reactivity keeps the UI in sync

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✨ Features

• ✅ Reactive models with automatic UI updates
• ✅ Object-wise reactivity (entire model rebuilds)
• ✅ Field-wise reactivity (only selected fields rebuild)
• ✅ Nested & shared models supported
• ✅ Many → One and Many ↔ Many relationships
• ✅ Multiple widgets can listen to the same model
• ✅ Minimal boilerplate
• ✅ ORM-style mental model (Objects + Relationships)

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🆚 Comparison

Feature	setState	Redux	ValueNotifier	Provider / ChangeNotifier	BLoC	Riverpod	MobX	reactive_orm
Plain Dart models	⚠️ Widget-bound	❌ Reducer-driven	⚠️ Wrapped value	❌ Extends notifier	❌ State classes	❌ Provider-based	⚠️ Annotated	✅ Plain Dart objects
Direct field mutation	⚠️ Inside widget	❌	⚠️ value = x	❌	❌	❌	⚠️ Observables	✅ model.field = value
Automatic UI updates	⚠️ Manual call	✅	✅	✅	✅	✅	✅	✅
Field-wise reactivity	❌	❌	❌	❌ Object-level	❌	❌	✅	✅ Field-wise + object-wise
Multiple widgets listening	❌	✅	Manual wiring	Manual wiring	Stream subscriptions	Provider wiring	Automatic	Automatic
Nested models	❌	❌	Manual	⚠️ Manual	❌	⚠️ Manual	⚠️ Manual	✅ Built-in
Relationship support	❌	❌	❌	❌	❌	❌	❌	✅ Many → One, Many ↔ Many
Boilerplate	Very Low	Very High	Medium	Medium	High	Medium	Medium	Minimal, ORM-style
Async-first design	❌	⚠️ Middleware	❌	⚠️ Optional	✅	✅	⚠️ Optional	❌
Immutability required	❌	✅	❌	❌	✅	✅	❌	❌
Mental model	Widget-local state	Global immutable store	Single reactive value	Observable objects	Event → State streams	Immutable containers	Observable variables	Live object graph (ORM-style)
Ideal for	Tiny local state	Large predictable apps	Simple values	Small–medium apps	Async-heavy logic	Predictable state	Explicit reactivity	Complex reactive domain models

In More Brief --------------

Provider vs reactive_orm

Feature	Provider / ChangeNotifier	reactive_orm
Plain Dart models	❌ Extends ChangeNotifier	✅ Plain Dart objects
Field assignment syntax	setX(); notifyListeners()	model.field = newValue
Automatic UI updates	✅	✅
Field-wise reactivity	❌ Object-level only	✅ Field-wise + object-wise
Multiple widgets listening	Manual provider wiring	Automatic
Nested models	⚠️ Manual propagation	✅ Built-in
Relationships	❌	✅ Many → One, Many ↔ Many
Boilerplate	Medium	Minimal, ORM-style
Ideal for	Small–medium apps	Complex reactive domain models

BLoC vs reactive_orm

Feature	BLoC	reactive_orm
State update style	Events → Streams → State	Direct field mutation
Immutability	Required	Optional / mutable
Boilerplate	High	Minimal
Field-wise reactivity	❌	✅
Nested models	❌	✅
Relationships	❌	✅ Many → One, Many ↔ Many
Async-first design	✅	❌
Mental model	Event-driven	ORM-style object graph
Ideal for	Complex async flows	Domain-driven UI state

Riverpod vs reactive_orm

Feature	Riverpod	reactive_orm
State model	Immutable snapshots	Live mutable objects
Update syntax	state = state.copyWith()	model.field = newValue
Field-wise reactivity	❌	✅
Nested models	⚠️ Manual	✅ Built-in
Relationships	❌	✅ Many → One, Many ↔ Many
Boilerplate	Medium	Minimal
Compile-time safety	✅ Strong	⚠️ Runtime
Ideal for	Predictable state flows	Relational domain models

MobX vs reactive_orm

Feature	MobX	reactive_orm
Reactivity declaration	Annotations + codegen	Automatic
Field-wise reactivity	✅	✅
Plain Dart models	⚠️ Annotated	✅ Plain Dart
Boilerplate	Medium	Minimal
Nested models	⚠️ Manual	✅ Built-in
Relationships	❌	✅ Many → One, Many ↔ Many
Tooling required	Code generation	None
Ideal for	Explicit reactive fields	ORM-style reactive objects

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🚀 Getting Started

Installation

dependencies:
  reactive_orm: <latest_version>

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🧩 Basic Usage

1️⃣ Create a Reactive Model

import 'package:reactive_orm/reactive_orm.dart';

class Task extends ReactiveModel {
  String _title;
  bool _completed = false;
  String _status = "Idle";

  Task({required String title}) : _title = title;

  String get title => _title;
  set title(String value) {
    if (_title != value) {
      _title = value;
      notifyListeners('title');
    }
  }

  bool get completed => _completed;
  set completed(bool value) {
    if (_completed != value) {
      _completed = value;
      notifyListeners('completed');
    }
  }

  String get status => _status;
  set status(String value) {
    if (_status != value) {
      _status = value;
      notifyListeners('status');
    }
  }
}

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2️⃣ Object-wise Reactivity (Whole Object)

Any field change rebuilds the widget:

final task = Task(title: "Object-wise");

ReactiveBuilder<Task>(
  model: task,
  builder: (t) => ListTile(
    title: Text(t.title),
    subtitle: Text(t.status),
    trailing: Checkbox(
      value: t.completed,
      onChanged: (v) => t.completed = v!,
    ),
  ),
);

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3️⃣ Field-wise Reactivity (Optimized)

Widget rebuilds only when specified fields change:

final task = Task(title: "Field-wise");

ReactiveBuilder<Task>(
  model: task,
  fields: ['completed', 'status'],
  builder: (t) => ListTile(
    title: Text(t.title),
    subtitle: Text(t.status),
    trailing: Checkbox(
      value: t.completed,
      onChanged: (v) => t.completed = v!,
    ),
  ),
);

• Rebuilds only when completed or status changes.
• Changes to other fields are ignored.

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🔗 Relationship Patterns

1-> Many → One (Aggregation)

Multiple models feed a single reactive observer:

class Dashboard extends ReactiveModel {
  final List<Task> sources;
  Dashboard(this.sources) {
    for (final task in sources) addNested(task);
  }
}

final dashboard = Dashboard([task1, task2]);

ReactiveBuilder<Dashboard>(
  model: dashboard,
  builder: (_) => Text("Dashboard updated"),
);

• ✔ Any task change updates the dashboard automatically.

2-> Many ↔ Many (Shared Models)

Same model instance used across multiple parents:

class Group extends ReactiveModel {
  final String name;
  final List<Task> tasks;

  Group({required this.name, required this.tasks}) {
    for (final task in tasks) addNested(task);
  }
}

• ✔ One task update reflects everywhere.
• ✔ No duplication or manual syncing required.

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🧠 How It Works (High Level)

• Models extend ReactiveModel.
• Field setters call notifyListeners(fieldName) when the value changes.
• ReactiveBuilder widgets listen to either:
  • Whole model (object-wise)
  • Specific fields (field-wise)
• Nested models propagate changes upward automatically.
• Widgets rebuild safely, respecting Flutter lifecycle.

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🛣 Roadmap

• Batch updates / transactions
• Async persistence hooks
• Database adapters (optional)
• DevTools / debug inspector
• Optional code generation

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🧪 Status

• Version: 0.0.7
• Stability: Stable (suitable for prototyping and early production)
• Focus: Reactive domain models & scalable state management

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📌 Summary

reactive_orm is ideal when you want:

• Clean Dart models with fine-grained reactivity
• A Reactive Object–Relationship Model for UI state
• Object-wise and field-wise rebuild control
• Nested and shared models without manual wiring
• Minimal boilerplate with a clear mental model
• A lightweight yet scalable state management solution for Flutter apps