Merge branch 'master' into feature/coroutines-1.7.0

Author: rickclephas

.idea/kotlinc.xml

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name       = 'KMMViewModelCore'
-  s.version    = '1.0.0-ALPHA-6'
+  s.version    = '1.0.0-ALPHA-7'
   s.summary    = 'Library to share Kotlin ViewModels with Swift'
 
   s.homepage   = 'https://github.com/rickclephas/KMM-ViewModel'

KMMViewModelCore.podspec

@@ -8,12 +8,26 @@
 import Combine
 import KMMViewModelCoreObjC
 
-/// Creates an `ObservableObject` for the specified `KMMViewModel`.
-/// - Parameter viewModel: The `KMMViewModel` to wrap in an `ObservableObject`.
+@available(*, deprecated, renamed: "observableViewModel")
 public func createObservableViewModel<ViewModel: KMMViewModel>(
     for viewModel: ViewModel
 ) -> ObservableViewModel<ViewModel> {
-    ObservableViewModel(viewModel)
+    observableViewModel(for: viewModel)
+}
+
+private var observableViewModelKey = "observableViewModel"
+
+/// Gets an `ObservableObject` for the specified `KMMViewModel`.
+/// - Parameter viewModel: The `KMMViewModel` to wrap in an `ObservableObject`.
+public func observableViewModel<ViewModel: KMMViewModel>(
+    for viewModel: ViewModel
+) -> ObservableViewModel<ViewModel> {
+    if let observableViewModel = objc_getAssociatedObject(viewModel, &observableViewModelKey) {
+        return observableViewModel as! ObservableViewModel<ViewModel>
+    }
+    let observableViewModel = ObservableViewModel(viewModel)
+    objc_setAssociatedObject(viewModel, &observableViewModelKey, observableViewModel, .OBJC_ASSOCIATION_ASSIGN)
+    return observableViewModel
 }
 
 /// An `ObservableObject` for a `KMMViewModel`.

KMMViewModelCore/ObservableViewModel.swift

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name       = 'KMMViewModelCoreObjC'
-  s.version    = '1.0.0-ALPHA-6'
+  s.version    = '1.0.0-ALPHA-7'
   s.summary    = 'Library to share Kotlin ViewModels with Swift'
 
   s.homepage   = 'https://github.com/rickclephas/KMM-ViewModel'

KMMViewModelCoreObjC.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name       = 'KMMViewModelSwiftUI'
-  s.version    = '1.0.0-ALPHA-6'
+  s.version    = '1.0.0-ALPHA-7'
   s.summary    = 'Library to share Kotlin ViewModels with SwiftUI'
 
   s.homepage   = 'https://github.com/rickclephas/KMM-ViewModel'

KMMViewModelSwiftUI.podspec

@@ -31,11 +31,10 @@ public extension View {
     /// Supplies a `KMMViewModel` to a view subhierarchy.
     /// - Parameter viewModel: The `KMMViewModel` to supply to a view subhierarchy.
     func environmentViewModel<ViewModel: KMMViewModel>(_ viewModel: ViewModel) -> some View {
-        environmentObject(createObservableViewModel(for: viewModel))
+        environmentObject(observableViewModel(for: viewModel))
     }
 
-    /// Supplies a `KMMViewModel` to a view subhierarchy.
-    /// - Parameter projectedValue: The `projectedValue` from e.g. `StateViewModel`.
+    @available(*, deprecated)
     func environmentViewModel<ViewModel: KMMViewModel>(_ projectedValue: ObservableViewModel<ViewModel>.Projection) -> some View {
         environmentObject(projectedValue.observableObject)
     }

KMMViewModelSwiftUI/EnvironmentViewModel.swift

@@ -15,14 +15,20 @@ public struct ObservedViewModel<ViewModel: KMMViewModel>: DynamicProperty {
 
     @ObservedObject private var observableObject: ObservableViewModel<ViewModel>
 
-    /// The underlying `KMMViewModel` referenced by the `ObservedViewModel`.
-    public var wrappedValue: ViewModel { observableObject.viewModel }
-    
     /// A projection of the observed `KMMViewModel` that creates bindings to its properties using dynamic member lookup.
     public var projectedValue: ObservableViewModel<ViewModel>.Projection
 
-    /// Creates an `ObservedViewModel` for the specified `KMMViewModel` projection.
-    /// - Parameter projectedValue: The `projectedValue` from e.g. `StateViewModel`.
+    /// The underlying `KMMViewModel` referenced by the `ObservedViewModel`.
+    public var wrappedValue: ViewModel {
+        get { observableObject.viewModel }
+        set {
+            let observableObject = observableViewModel(for: newValue)
+            self.observableObject = observableObject
+            self.projectedValue = ObservableViewModel.Projection(observableObject)
+        }
+    }
+    
+    @available(*, deprecated)
     public init(_ projectedValue: ObservableViewModel<ViewModel>.Projection) {
         self.observableObject = projectedValue.observableObject
         self.projectedValue = projectedValue
@@ -31,7 +37,7 @@ public struct ObservedViewModel<ViewModel: KMMViewModel>: DynamicProperty {
     /// Creates an `ObservedViewModel` for the specified `KMMViewModel`.
     /// - Parameter wrappedValue: The `KMMViewModel` to observe.
     public init(wrappedValue: ViewModel) {
-        let observableObject = createObservableViewModel(for: wrappedValue)
+        let observableObject = observableViewModel(for: wrappedValue)
         self.observableObject = observableObject
         self.projectedValue = ObservableViewModel.Projection(observableObject)
     }

KMMViewModelSwiftUI/ObservedViewModel.swift

@@ -27,6 +27,6 @@ public struct StateViewModel<ViewModel: KMMViewModel>: DynamicProperty {
     /// Creates a `StateViewModel` for the specified `KMMViewModel`.
     /// - Parameter wrappedValue: The `KMMViewModel` to observe.
     public init(wrappedValue: @autoclosure @escaping () -> ViewModel) {
-        self._observableObject = StateObject(wrappedValue: createObservableViewModel(for: wrappedValue()))
+        self._observableObject = StateObject(wrappedValue: observableViewModel(for: wrappedValue()))
     }
 }

KMMViewModelSwiftUI/StateViewModel.swift

@@ -4,12 +4,13 @@ A library that allows you to share ViewModels between Android and iOS.
 
 ## Compatibility
 
-The latest version of the library uses Kotlin version `1.8.20`.  
+The latest version of the library uses Kotlin version `1.8.21`.  
 Compatibility versions for newer Kotlin versions are also available:
 
 | Version       | Version suffix  |   Kotlin   | Coroutines |
 |---------------|-----------------|:----------:|:----------:|
-| **_latest_**  | **_no suffix_** | **1.8.20** | **1.6.4**  |
+| **_latest_**  | **_no suffix_** | **1.8.21** | **1.6.4**  |
+| 1.0.0-ALPHA-6 | _no suffix_     |   1.8.20   |   1.6.4    |
 | 1.0.0-ALPHA-4 | _no suffix_     |   1.8.10   |   1.6.4    |
 | 1.0.0-ALPHA-3 | _no suffix_     |   1.8.0    |   1.6.4    |
 
@@ -22,13 +23,12 @@ dependencies {
 }
 ```
 
-Create your ViewModels almost as you would in Android:
+And create your ViewModels:
 ```kotlin
 import com.rickclephas.kmm.viewmodel.KMMViewModel
 import com.rickclephas.kmm.viewmodel.MutableStateFlow
 import com.rickclephas.kmm.viewmodel.stateIn
 
-// 1: use KMMViewModel instead of ViewModel
 open class TimeTravelViewModel: KMMViewModel() {
 
     private val clockTime = Clock.time
@@ -37,10 +37,8 @@ open class TimeTravelViewModel: KMMViewModel() {
      * A [StateFlow] that emits the actual time.
      */
     val actualTime = clockTime.map { formatTime(it) }
-        // 2: supply viewModelScope to your stateIn calls
         .stateIn(viewModelScope, SharingStarted.WhileSubscribed(), "N/A")
 
-    // 3: supply viewModelScope to your MutableStateFlows
     private val _travelEffect = MutableStateFlow<TravelEffect?>(viewModelScope, null)
     /**
      * A [StateFlow] that emits the applied [TravelEffect].
@@ -49,21 +47,55 @@ open class TimeTravelViewModel: KMMViewModel() {
 }
 ```
 
-You need to use `viewModelScope` wherever possible to propagate state changes to iOS.  
-In other cases you can access the `ViewModelScope.coroutineScope` property directly.
+As you might notice it isn't much different from an Android ViewModel.  
+The most obvious difference is the `KMMViewModel` superclass:
+
+```diff
+- import androidx.lifecycle.ViewModel
++ import com.rickclephas.kmm.viewmodel.KMMViewModel
+
+- open class TimeTravelViewModel: ViewModel() {
++ open class TimeTravelViewModel: KMMViewModel() {
+```
+
+Besides that there are only 2 minor differences.  
+The first being a different import for `stateIn`:
+
+```diff
+- import kotlinx.coroutines.flow.stateIn
++ import com.rickclephas.kmm.viewmodel.stateIn
+
+        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(), "N/A")
+```
+
+And the second being a different `MutableStateFlow` constructor:
+
+```diff
+- import kotlinx.coroutines.flow.MutableStateFlow
++ import com.rickclephas.kmm.viewmodel.MutableStateFlow
+
+-    private val _travelEffect = MutableStateFlow<TravelEffect?>(null)
++    private val _travelEffect = MutableStateFlow<TravelEffect?>(viewModelScope, null)
+```
+
+These minor differences will make sure that any state changes are propagate to iOS.  
+
+> **Note**: `viewModelScope` is a wrapper around the actual `CoroutineScope` which can be accessed 
+> via the `ViewModelScope.coroutineScope` property.
 
 ### KMP-NativeCoroutines
 
-Use the `@NativeCoroutinesState` annotation from [KMP-NativeCoroutines](https://github.com/rickclephas/KMP-NativeCoroutines)
+I highly recommend you to use the `@NativeCoroutinesState` annotation from
+[KMP-NativeCoroutines](https://github.com/rickclephas/KMP-NativeCoroutines)
 to turn your `StateFlow`s into properties in Swift:
 
 ```kotlin
 @NativeCoroutinesState
 val travelEffect = _travelEffect.asStateFlow()
 ```
 
-Checkout the [README](https://github.com/rickclephas/KMP-NativeCoroutines/blob/master/README.md)
-for more information and installation instructions for KMP-NativeCoroutines.
+Checkout the KMP-NativeCoroutines [README](https://github.com/rickclephas/KMP-NativeCoroutines/blob/master/README.md)
+for more information and installation instructions.
 
 <details><summary>Alternative</summary>
 <p>
@@ -92,7 +124,7 @@ class TimeTravelFragment: Fragment(R.layout.fragment_time_travel) {
 }
 ```
 
-> **Note:** support for Jetpack Compose is coming soon.
+> **Note:** improved support for Jetpack Compose is coming soon.
 
 ## Swift
 

README.md

@@ -8,7 +8,7 @@ buildscript {
 
 allprojects {
     group = "com.rickclephas.kmm"
-    version = "1.0.0-ALPHA-6"
+    version = "1.0.0-ALPHA-7"
 
     repositories {
         mavenCentral()