⚡ reactivity

A minimal and elegant state management solution for Flutter
Rebuild only what matters — with zero boilerplate.

✅ Built for performance
🧠 Easy to learn
🎯 Flutter-native
💙 Perfect for UI-driven apps

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🧨 The Power of ValueState + Named Records

The core feature of reactivity is seamless support for Dart Records via ValueState.

With ValueState, you manage multiple pieces of state — like name, age, isAdmin — using a single named record, with full type safety and zero boilerplate.

🤯 Example: Clean and Reactive

final user = ValueState<({String name, int age, bool isAdmin})>();

ReactiveState(user.on(
  (u) => Text('Name: ${u.name}, Age: ${u.age}, Admin: ${u.isAdmin}'),
));

user.refreshWith((name: 'Felipe', age: 30, isAdmin: true));

✔ No classes
✔ Fully typed
✔ Instantly reactive
✔ Native Dart syntax

If you love Dart’s record syntax, this will feel like magic.

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✨ Features Overview

• 🔄 refresh() — global rebuild trigger
• 🧩 Reactive, ReactiveState, ReactiveStatus, ReactiveShow — declarative reactive widgets
• 🧱 ValueState, InitedState, VoidState — flexible state containers
• 🚦 refreshStatus() — reactive flow using enums
• ❓ ReactiveNullable, ReactiveNullableList — handle nulls & empty states gracefully

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🚀 Getting Started

Add the dependency:

dependencies:
  reactivity: ^1.0.0

Import it in your Dart file:

import 'package:reactivity/reactivity.dart';

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⚙ Usage Examples

Global rebuild

int counter = 0;

Reactive(() => Text('Counter: $counter'));

counter++;
refresh(); // Triggers rebuild

Rebuild by key

final myKey = ReactiveKey();

Reactive(() => Text("Hello"), reactiveKey: myKey);

refreshOnly(myKey); // Rebuild just this one

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🧱 State Containers

InitedState

final name = InitedState<String>("Kaian");

ReactiveState(name.on((value) => Text("Hello $value")));

name.refreshWith("Felipe");

ValueState

final count = ValueState<int>();

ReactiveState(count.on((value) => Text('Count: $value')));

count.refreshWith(1);
count.refreshUpdate((value) => value! + 1);

VoidState

final trigger = VoidState();

ReactiveState(trigger.on(() => Text("Triggered!")));

trigger.refresh();

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🚦 ReactiveStatus

enum Status { loading, success, error }

refreshStatus(Status.loading);

ReactiveStatus<Status>(
  cases: {
    Status.loading: () => CircularProgressIndicator(),
    Status.success: () => Text("Done!"),
    Status.error: () => Text("Oops"),
  },
  defaultCase: () => Text("Idle"),
);

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🎭 Conditional Rendering

ReactiveShow

bool isLogged = false;

ReactiveShow(
  showIf: () => isLogged,
  builder: () => Text("Welcome"),
  elseShow: Text("Login required"),
);

isLogged = true;
refresh();

ReactiveNullable

String? username;

ReactiveNullable<String>(
  value: username,
  builder: (name) => Text("Hi $name"),
  ifNull: Text("No user"),
);

username = "Felipe";
refresh();

ReactiveNullableList

List<String>? items;

ReactiveNullableList<String>(
  values: items,
  builder: (list) => ListView(children: list.map(Text.new).toList()),
  ifNull: CircularProgressIndicator(),
  ifEmpty: Text("No items"),
);

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✅ Why reactivity?

• 🌟 First-class support for Dart Named Records
• 🚫 No context, no classes, no scope hassles
• 🧼 Clean and minimal API
• 💬 Declarative, expressive, and beautiful
• 🎯 Native to the Flutter widget tree

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🤝 Contributing

Got ideas or found bugs?
Feel free to open issues or submit a pull request. Let's build this together!

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📄 License

MIT License © Felipe Kaian

Libraries

reactive

reactive_notifier

reactive_nullable

reactive_nullable_list

reactive_show

reactive_state

reactive_states

reactive_status

reactivity