maac_mvvm 0.2.3

maac_mvvm is a package supporting easy MVVM pattern implementation without any dependency injection wrapping, allowing freedom of choice.

maac_mvvm

The core package of the MAAC ecosystem. It provides the base classes for the MVVM pattern and a lifecycle management system that mirrors the robustness of Android development.

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🚀 Key Features

• Lifecycle Synchronization: Android-inspired onResume, onPause, and onDispose hooks.
• Reactive State: StreamData for clean data binding.
• Efficient Rebuilds: StreamDataConsumer for granular UI updates, with an optional useCache predicate to skip rebuilding for values that shouldn't visually change the UI.
• Combining Multiple Streams: StreamDataConsumer2/StreamDataConsumer3 for rebuilding off 2 or 3 StreamData sources at once, or MergeStreamDataConsumer for combining any number of them.

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📖 Usage

1. Define your ViewModel

class CounterViewModel extends ViewModel {
  late final _counter = 0.mutableData(this);
  late final counter = _counter.streamData;

  void increment() => _counter.postValue(counter.data + 1);
}

2. Build your UI

class CounterPage extends ViewModelWidget<CounterViewModel> {
  @override
  CounterViewModel createViewModel() => CounterViewModel();

  @override
  Widget build(BuildContext context, CounterViewModel viewModel) {
    return Scaffold(
      body: Center(
        child: StreamDataConsumer<int>(
          streamData: viewModel.counter,
          builder: (context, data) => Text('$data'),
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: viewModel.increment,
        child: Icon(Icons.add),
      ),
    );
  }
}

3. Combine Multiple Streams

Rebuild off more than one StreamData at once with StreamDataConsumer2/StreamDataConsumer3 — each source's latest value is passed straight into the builder, fully typed, no manual combining:

StreamDataConsumer2<int, bool>(
  streamData1: viewModel.counter,
  streamData2: viewModel.isFavorite,
  builder: (context, count, isFavorite) => Text('$count ${isFavorite ? '★' : ''}'),
)

For more than 3 sources, or a source count that isn't known ahead of time, drop down to MergeStreamDataConsumer — the primitive StreamDataConsumer2/3 are built on. It only signals "something changed, rebuild"; read whichever StreamData.data you actually need directly inside the builder:

MergeStreamDataConsumer(
  streams: [viewModel.counter, viewModel.isFavorite, viewModel.themeLabel],
  builder: (context) => Text(
    '${viewModel.counter.data} ${viewModel.isFavorite.data ? '★' : ''} (${viewModel.themeLabel.data})',
  ),
)

All 3 rebuild whenever any source emits — there's no pairing/waiting between sources, so one fast-updating stream never gets held back by a slower one.

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🧭 Documentation

For detailed API specifications, installation guides, and tutorials, please visit our centralized documentation hub:

👉 MAAC Documentation Hub

Specific Guides:

• 🛠️ Core API Specification
• 🏗️ Architecture Philosophy
• 🚦 Quick Start Guide

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🤝 Contributing

Contributions are welcome! Please visit the main repository for more information.