just_manager

just_manager is a lightweight Flutter state management package built around a flexible and easy-to-use JM (Just Manage) wrapper. It simplifies reactive state updates, multi-listenable management, and rebuild control without introducing heavy boilerplate.

Features

Simple, callable JM<T> wrapper for values.
Easily set, get, and notify listeners.
Support for multiple listenables with JMListener and multiUp.
Optional JMScaffold for auto-rebuilding Scaffold body.
Minimal boilerplate compared to ChangeNotifier and ValueNotifier.

Installation

Add this to your pubspec.yaml:

dependencies:
  just_manager:
    git:
      url: https://github.com/JeaFrid/just-manager.git

Then run:

flutter pub get

Quick Start

1. Create a JM

import 'package:just_manager/just_manager.dart';

final counter = JM<int>(0);

2. Read and Update

// Get current value
print(counter()); // 0

// Update without notifying listeners
counter.callSet(5);

// Update and notify listeners
counter.set(10);

3. Listen for Changes

JMListener(
  listenables: [counter],
  childBuilder: () {
    return Text('Counter: ${counter()}');
  },
);

4. Rebuild Multiple JM Instances

final name = JM<String>('Alice');
final age = JM<int>(25);

// Manually notify all
JM.multiUp([counter, name, age]);

5. Using JMScaffold

JMScaffold is a drop-in replacement for Scaffold that rebuilds its body whenever the specified JM listenables change.

JMScaffold(
  listenables: [counter],
  appBar: AppBar(title: Text('JM Example')),
  body: () {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Text('Counter: ${counter()}'),
          ElevatedButton(
            onPressed: () => counter.set(counter() + 1),
            child: Text('Increment'),
          ),
        ],
      ),
    );
  },
);

API Overview

JM

JM(T value) → Initialize JM with a value.
T call() → Returns the current value.
void callSet(T newValue) → Sets value without notifying listeners.
void set(T newValue) → Sets value and notifies listeners.
void up() → Manually notify listeners.
static void multiUp(List<JM> list) → Notify multiple JM instances at once.

JMListener

JMListener(listenables: [...], childBuilder: () => Widget) → Rebuilds child widget when any JM in listenables changes.

JMScaffold

Drop-in Scaffold replacement.
listenables → List of JM instances to rebuild body when updated.
body → Builder function that returns the body widget.

Why Use JM?

Simplifies state management compared to ChangeNotifier or ValueNotifier.
Callable API allows cleaner and shorter code.
Built-in support for multiple listenables.
Minimalistic and flexible; works with any Flutter widget tree.