V2

.vscode/launch.json

@@ -5,24 +5,16 @@
     "version": "0.2.0",
     "configurations": [
         {
-            "name": "example",
-            "cwd": "example",
+            "name": "example_login",
+            "cwd": "examples/login_posts_list",
             "request": "launch",
             "type": "dart"
         },
         {
-            "name": "example (profile mode)",
-            "cwd": "example",
+            "name": "counter",
+            "cwd": "examples/counter",
             "request": "launch",
-            "type": "dart",
-            "flutterMode": "profile"
-        },
-        {
-            "name": "example (release mode)",
-            "cwd": "example",
-            "request": "launch",
-            "type": "dart",
-            "flutterMode": "release"
+            "type": "dart"
         }
     ]
 }

CHANGELOG.md

@@ -1,3 +1,34 @@
+## 2.0.0
+
+**🚨 BREAKING CHANGES - Complete Architecture Rewrite**
+
+This is a major rewrite of the MVI package with significant breaking changes.
+
+### New Architecture
+
+* **Replaced signals with ValueListenable**: Now uses Flutter's built-in ValueListenable and ValueNotifier for reactive state management
+* **Dual ViewModel approach**: 
+  - `SimpleViewModel` for basic state management without effects
+  - `ViewModel` for full MVI pattern with effects support
+* **New mixins**: 
+  - `SimpleViewModelMixin` for connecting widgets to SimpleViewModels
+  - `ViewModelMixin` for connecting widgets to ViewModels with effects
+* **Method rename**: `provideViewModel()` renamed to `createViewModel()` for better clarity
+
+### Migration Guide
+
+This version is not backward compatible. To migrate:
+
+1. Replace `BaseViewModel` with either `SimpleViewModel` or `ViewModel`
+2. Update your mixins to use `SimpleViewModelMixin` or `ViewModelMixin`
+3. Rename `provideViewModel()` to `createViewModel()`
+4. Replace signals-based state observation with ValueListenableBuilder
+
+### Examples
+
+* Added complete counter example demonstrating basic MVI pattern
+* Updated login/posts example with new architecture
+
 ## 1.0.6
 
 * Log information about the ViewModel when debugLabel is not null

README.md

@@ -1,16 +1,3 @@
-<!--
-This README describes the package. If you publish this package to pub.dev,
-this README's contents appear on the landing page for your package.
-
-For information about how to write a good package README, see the guide for
-[writing package pages](https://dart.dev/tools/pub/writing-package-pages).
-
-For general information about developing packages, see the Dart guide for
-[creating packages](https://dart.dev/guides/libraries/create-packages)
-and the Flutter guide for
-[developing packages and plugins](https://flutter.dev/to/develop-packages).
--->
-
 <p align="center">
   <a href="https://pub.dev/packages/mvi">
     <img alt="Pub Version" src="https://img.shields.io/pub/v/mvi">
@@ -28,45 +15,67 @@ and the Flutter guide for
 
 # MVI - Model-View-Intent for Flutter
 
-An implementation of the MVI (Model-View-Intent) pattern for Flutter that uses the `signals` package for managing state.
+A clean and efficient implementation of the MVI (Model-View-Intent) pattern for Flutter using ValueListenable for reactive state management.
 
-This package provides a basic structure to implement the MVI pattern in your Flutter projects, helping you to build reactive and predictable user interfaces.
+This package provides a robust architecture to implement the MVI pattern in your Flutter projects, helping you build reactive, predictable, and testable user interfaces.
 
 ## What is MVI?
 
-MVI is a unidirectional data flow architecture pattern that helps in managing the state of your application in a more predictable way. It is composed of three main components:
+MVI is a unidirectional data flow architecture pattern that helps manage application state predictably. It consists of three main components:
 
 -   **Model**: Represents the state of the application. It's an immutable object that holds all the data needed for the view.
 -   **View**: The user interface (UI) that displays the state. In Flutter, this would be your widgets.
 -   **Intent**: Represents an intention to change the state. These are usually triggered by user interactions with the UI.
 
-## Core Concepts
+Additionally, this implementation supports **Effects** for handling one-time side effects like navigation, showing snackbars, or other UI actions that don't affect state.
+
+## Core Components
+
+### Base Classes
 
-This implementation is built around a few core components:
+-   **`BaseState`**: Abstract base class for all state objects. States should be immutable.
+-   **`BaseEvent`**: Abstract base class for all events (intents) that can trigger state changes.
+-   **`BaseEffect`**: Abstract base class for all effects (one-time side effects).
 
--   `BaseViewModel`: A class that holds the business logic. It receives intents, processes them, and emits new states.
--   `ViewModelMixin`: A mixin that can be used with a `StatefulWidget`'s `State` to automatically listen to state changes from a `BaseViewModel` and rebuild the UI.
+### ViewModels
 
-## State Management with Signals
+-   **`SimpleViewModel`**: For state management without effects.
+-   **`ViewModel`**: For state management with effects support.
 
-This MVI implementation uses the [signals](https://pub.dev/packages/signals) package to manage the state. The state of a `BaseViewModel` is a `Signal` that can be observed by the UI. When a new state is emitted, the UI is automatically rebuilt.
+### Mixins
+
+-   **`SimpleViewModelMixin`**: Mixin for connecting widgets to SimpleViewModels.
+-   **`ViewModelMixin`**: Mixin for connecting widgets to ViewModels with effects support.
+
+## State Management with ValueListenable
+
+This MVI implementation uses Flutter's built-in `ValueListenable` and `ValueNotifier` for reactive state management. The state is observable and automatically triggers UI rebuilds when changed.
 
 ## Getting Started
 
 Add the package to your `pubspec.yaml`:
 
 ```yaml
 dependencies:
-  mvi: ^1.0.0
+  mvi: ^2.0.0
 ```
 
 Then, run `flutter pub get`.
 
-## Usage
+## Example
+
+Check the examples folder for complete implementations and tests:
+
+- [`examples/counter/`](examples/counter/) - Simple counter app demonstrating basic MVI pattern
+- [`examples/login_posts_list/`](examples/login_posts_list/) - Complete app with login flow and data fetching
 
-Check the example folder for a detailed implementation with tests.
+## Features
 
-**Note**: The architecture in this example is designed solely for simplicity and demonstration purposes.
+- ✅ **Reactive State Management**: Built on Flutter's ValueListenable
+- ✅ **Effects Support**: Handle side effects like navigation and dialogs
+- ✅ **Performance Optimized**: Selectors prevent unnecessary rebuilds
+- ✅ **Debug Support**: Built-in logging for development
+- ✅ **Testable**: Easy to unit test ViewModels and business logic
 
 ## Contributing
 

examples/counter/.gitignore

@@ -0,0 +1,45 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.build/
+.buildlog/
+.history
+.svn/
+.swiftpm/
+migrate_working_dir/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# The .vscode folder contains launch configuration and tasks you configure in
+# VS Code which you may wish to be included in version control, so this line
+# is commented out by default.
+#.vscode/
+
+# Flutter/Dart/Pub related
+**/doc/api/
+**/ios/Flutter/.last_build_id
+.dart_tool/
+.flutter-plugins
+.flutter-plugins-dependencies
+.pub-cache/
+.pub/
+/build/
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json
+
+# Android Studio will place build artifacts here
+/android/app/debug
+/android/app/profile
+/android/app/release

examples/counter/.metadata

@@ -0,0 +1,33 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: "d7b523b356d15fb81e7d340bbe52b47f93937323"
+  channel: "stable"
+
+project_type: app
+
+# Tracks metadata for the flutter migrate command
+migration:
+  platforms:
+    - platform: root
+      create_revision: d7b523b356d15fb81e7d340bbe52b47f93937323
+      base_revision: d7b523b356d15fb81e7d340bbe52b47f93937323
+    - platform: android
+      create_revision: d7b523b356d15fb81e7d340bbe52b47f93937323
+      base_revision: d7b523b356d15fb81e7d340bbe52b47f93937323
+    - platform: ios
+      create_revision: d7b523b356d15fb81e7d340bbe52b47f93937323
+      base_revision: d7b523b356d15fb81e7d340bbe52b47f93937323
+
+  # User provided section
+
+  # List of Local paths (relative to this file) that should be
+  # ignored by the migrate tool.
+  #
+  # Files that are not part of the templates will be ignored by default.
+  unmanaged_files:
+    - 'lib/main.dart'
+    - 'ios/Runner.xcodeproj/project.pbxproj'

examples/counter/README.md

@@ -0,0 +1,37 @@
+# Counter MVI Example
+
+A simple counter app demonstrating the MVI pattern using the `mvi` package.
+
+## Features
+
+- Increment and decrement counter
+- Uses `SimpleViewModel` for basic state management without effects
+- Demonstrates the MVI pattern with clean separation of concerns
+
+## Structure
+
+```
+lib/
+├── counter/
+│   ├── view_model/
+│   │   ├── counter_state.dart      # State definition
+│   │   ├── counter_event.dart      # Events (Increment/Decrement)
+│   │   └── counter_view_model.dart # Business logic
+│   └── counter_page.dart           # UI implementation
+└── main.dart                       # App entry point
+```
+
+## Key Components
+
+- **CounterState**: Holds the counter value
+- **CounterEvent**: Defines increment and decrement actions
+- **CounterViewModel**: Handles business logic and state updates
+- **CounterPage**: UI that connects to the ViewModel using `SimpleViewModelMixin`
+
+## Running
+
+```bash
+flutter run
+```
+
+This example demonstrates the basic MVI pattern without effects, making it perfect for understanding the core concepts.

examples/counter/android/app/build.gradle.kts

@@ -0,0 +1,44 @@
+plugins {
+    id("com.android.application")
+    id("kotlin-android")
+    // The Flutter Gradle Plugin must be applied after the Android and Kotlin Gradle plugins.
+    id("dev.flutter.flutter-gradle-plugin")
+}
+
+android {
+    namespace = "com.example.counter"
+    compileSdk = flutter.compileSdkVersion
+    ndkVersion = flutter.ndkVersion
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_11
+        targetCompatibility = JavaVersion.VERSION_11
+    }
+
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_11.toString()
+    }
+
+    defaultConfig {
+        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
+        applicationId = "com.example.counter"
+        // You can update the following values to match your application needs.
+        // For more information, see: https://flutter.dev/to/review-gradle-config.
+        minSdk = flutter.minSdkVersion
+        targetSdk = flutter.targetSdkVersion
+        versionCode = flutter.versionCode
+        versionName = flutter.versionName
+    }
+
+    buildTypes {
+        release {
+            // TODO: Add your own signing config for the release build.
+            // Signing with the debug keys for now, so `flutter run --release` works.
+            signingConfig = signingConfigs.getByName("debug")
+        }
+    }
+}
+
+flutter {
+    source = "../.."
+}

examples/counter/android/app/src/main/AndroidManifest.xml

@@ -0,0 +1,45 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <application
+        android:label="counter"
+        android:name="${applicationName}"
+        android:icon="@mipmap/ic_launcher">
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:launchMode="singleTop"
+            android:taskAffinity=""
+            android:theme="@style/LaunchTheme"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
+            <!-- Specifies an Android theme to apply to this Activity as soon as
+                 the Android process has started. This theme is visible to the user
+                 while the Flutter UI initializes. After that, this theme continues
+                 to determine the Window background behind the Flutter UI. -->
+            <meta-data
+              android:name="io.flutter.embedding.android.NormalTheme"
+              android:resource="@style/NormalTheme"
+              />
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+                <category android:name="android.intent.category.LAUNCHER"/>
+            </intent-filter>
+        </activity>
+        <!-- Don't delete the meta-data below.
+             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
+    </application>
+    <!-- Required to query activities that can process text, see:
+         https://developer.android.com/training/package-visibility and
+         https://developer.android.com/reference/android/content/Intent#ACTION_PROCESS_TEXT.
+
+         In particular, this is used by the Flutter engine in io.flutter.plugin.text.ProcessTextPlugin. -->
+    <queries>
+        <intent>
+            <action android:name="android.intent.action.PROCESS_TEXT"/>
+            <data android:mimeType="text/plain"/>
+        </intent>
+    </queries>
+</manifest>

examples/counter/android/app/src/main/kotlin/com/example/counter/MainActivity.kt

@@ -0,0 +1,5 @@
+package com.example.counter
+
+import io.flutter.embedding.android.FlutterActivity
+
+class MainActivity : FlutterActivity()