Feat/add reaction when

.gitignore

@@ -1,7 +1,7 @@
 /secret.properties
 /local.properties
-/build/
 /.gradle/
 /.idea/
 /mobk-compose/build/
 /mobk-core/build/
+build/

README.md

@@ -68,7 +68,7 @@ kotlin {
 
 ### SwiftUI ###
 
-You need add the following file [Observer.kt](./mobk-swift/Observer.kt) to your
+You need add the following file [Observer.swift](./mobk-swift/Observer.swift) to your
 Xcode project. Be sure to replace the import line with the name of your Kotlin
 framework.
 
@@ -133,3 +133,108 @@ Observer {
     }
 }
 ```
+
+### MobK ViewModel ###
+
+#### Dependency ####
+Add the mobk-viewmodel dependency to your commonMain dependencies :
+
+``` gradle
+kotlin {
+    ...
+    sourceSets {
+        commonMain {
+            dependencies {
+                ...
+                api "io.monkeypatch:mobk-viewmodel:$mobk_version"
+            }
+        }
+```   
+
+#### Usage ####
+
+The ViewModel class is a simple class that can be used to store state and logic for your application.
+It is designed to be used with SwiftUI and Jetpack Compose, but can be used with any UI toolkit.
+
+It provides reactions, that respect lifecycle of the ViewModel, and can be used to perform side effects.
+
+``` kotlin
+class CounterViewModel: MobKViewModel {
+    var counter by observable(0)
+
+    val counterWatch = reaction(
+        delay = 5.seconds,
+        trackingFn = { counter }) { counter ->
+        if (counter != null && counter > 10) {
+            message = "Counter is too high"
+        }
+    }
+
+    val warningWatch = whenReaction(predicate = { counter > 12 }) {
+        message = "Counter is really too high"
+    }
+
+    fun increment() {
+        counter++
+    }
+
+    @override
+    fun onCleared() {
+       super.onCleared()
+         // Do some cleanup here
+    }
+}
+```
+
+#### SwiftUI ####
+
+You need add the following file [MobKViewModel.swift](./mobk-swift/MobKViewModel.swift) to your Xcode project. Be sure to replace the import line with the name of your Kotlin framework.
+
+After that, you can use the @VM property wrapper to manage the lifecycle of your ViewModel. When component is destroyed, the ViewModel will be cleared. 
+Usually, you may also use the @StateObject property wrapper to manage the persistence of your ViewModel.
+
+``` swift
+struct ContentView: View {
+   @StateObject @VM var counterViewModel: CounterViewModel = CounterViewModel()
+
+    var body: some View {
+        VStack {
+            Text(verbatim: self.counterViewModel.counter)
+
+            HStack {
+                Button(action: {
+                    self.counterViewModel.increment()
+                }) {
+                    Text("Increment")
+                }
+            }
+        }
+    }
+}
+```
+
+If your view model has a dependency on a parameter, you have to use the following syntax:
+
+``` swift
+struct ContentView: View {
+   @StateObject @VM var counterViewModel: CounterViewModel
+
+    init(counter: Int) {
+        _counterViewModel = asStateObject(CounterViewModel(counter: counter))
+    }
+
+    var body: some View {
+        VStack {
+            Text(verbatim: self.counterViewModel.counter)
+
+            HStack {
+                Button(action: {
+                    self.counterViewModel.increment()
+                }) {
+                    Text("Increment")
+                }
+            }
+        }
+    }
+}
+```

build.gradle.kts

@@ -0,0 +1,27 @@
+buildscript {
+    repositories {
+        google()
+        mavenCentral()
+    }
+
+    dependencies {
+        classpath("com.android.tools.build:gradle:8.1.1")
+        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.5.21")
+        classpath("org.jetbrains.compose:compose-gradle-plugin:1.5.1")
+    }
+}
+
+plugins {
+    kotlin("multiplatform") version "1.9.10"
+}
+
+allprojects {
+    repositories {
+        google()
+        mavenCentral()
+    }
+}
+
+kotlin {
+    jvm()
+}

gradle.properties

@@ -1 +1,2 @@
-android.useAndroidX=true
+android.useAndroidX=true
+org.jetbrains.compose.experimental.uikit.enabled=true

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Wed Aug 11 10:48:24 CEST 2021
+#Wed Sep 20 20:55:00 CEST 2023
 distributionBase=GRADLE_USER_HOME
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.0.2-bin.zip
 distributionPath=wrapper/dists
-zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip
 zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists