add ConfirmationEvent

Author: Alex

reactiveviewmodel/build.gradle

@@ -44,7 +44,7 @@ afterEvaluate {
             release(MavenPublication) {
                 from components.release
                 groupId = 'com.alexdeww.reactiveviewmodel'
-                version = '2.3.8'
+                version = '2.3.9'
             }
         }
     }

reactiveviewmodel/src/main/java/com/alexdeww/reactiveviewmodel/core/ReactiveViewModel.kt

@@ -3,6 +3,7 @@ package com.alexdeww.reactiveviewmodel.core
 import androidx.lifecycle.ViewModel
 import com.alexdeww.reactiveviewmodel.core.common.RvmComponent
 import com.alexdeww.reactiveviewmodel.core.property.Action
+import com.alexdeww.reactiveviewmodel.core.property.ConfirmationEvent
 import com.alexdeww.reactiveviewmodel.core.property.Event
 import com.alexdeww.reactiveviewmodel.core.property.State
 import io.reactivex.rxjava3.disposables.CompositeDisposable
@@ -36,6 +37,12 @@ abstract class ReactiveViewModel : ViewModel(), RvmComponent {
     protected fun eventNone(debounceInterval: Long? = null): Event<Unit> =
         Event(debounceInterval)
 
+    protected fun <T : Any> confirmationEvent(debounceInterval: Long? = null): ConfirmationEvent<T> =
+        ConfirmationEvent(debounceInterval)
+
+    protected fun confirmationEventNone(debounceInterval: Long? = null): ConfirmationEvent<Unit> =
+        ConfirmationEvent(debounceInterval)
+
     protected fun <T : Any> action(debounceInterval: Long? = null): Action<T> =
         Action(debounceInterval)
 

reactiveviewmodel/src/main/java/com/alexdeww/reactiveviewmodel/core/RvmExtensions.kt

@@ -5,6 +5,7 @@ import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.Observer
 import com.alexdeww.reactiveviewmodel.core.property.Action
+import com.alexdeww.reactiveviewmodel.core.property.ConfirmationEvent
 import com.alexdeww.reactiveviewmodel.core.property.Event
 import com.alexdeww.reactiveviewmodel.core.property.State
 import io.reactivex.rxjava3.core.*
@@ -19,11 +20,20 @@ fun <T> LiveData<T>.observe(owner: LifecycleOwner, action: OnLiveDataAction<T>):
     return observer
 }
 
-fun <T : Any> Event<T>.observe(owner: LifecycleOwner, action: OnLiveDataAction<T>): Observer<T> =
-    liveData.observe(owner = owner, action = action)
+fun <T : Any> Event<T>.observe(
+    owner: LifecycleOwner,
+    action: OnLiveDataAction<T>
+): Observer<T> = liveData.observe(owner = owner, action = action)
 
-fun <T : Any> State<T>.observe(owner: LifecycleOwner, action: OnLiveDataAction<T>): Observer<T> =
-    liveData.observe(owner = owner, action = action)
+fun <T : Any> ConfirmationEvent<T>.observe(
+    owner: LifecycleOwner,
+    action: OnLiveDataAction<T>
+): Observer<T> = liveData.observe(owner = owner, action = action)
+
+fun <T : Any> State<T>.observe(
+    owner: LifecycleOwner,
+    action: OnLiveDataAction<T>
+): Observer<T> = liveData.observe(owner = owner, action = action)
 
 fun Action<Unit>.call() = call(Unit)
 

reactiveviewmodel/src/main/java/com/alexdeww/reactiveviewmodel/core/RvmViewComponent.kt

@@ -6,6 +6,7 @@ import android.widget.RatingBar
 import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.Observer
+import com.alexdeww.reactiveviewmodel.core.property.ConfirmationEvent
 import com.alexdeww.reactiveviewmodel.core.property.Event
 import com.alexdeww.reactiveviewmodel.core.property.State
 import com.alexdeww.reactiveviewmodel.widget.*
@@ -31,6 +32,9 @@ interface RvmViewComponent {
     fun <T : Any> Event<T>.observe(action: OnLiveDataAction<T>): Observer<T> =
         observe(componentLifecycleOwner, action)
 
+    fun <T : Any> ConfirmationEvent<T>.observe(action: OnLiveDataAction<T>): Observer<T> =
+        observe(componentLifecycleOwner, action)
+
     fun <T : Any> DisplayableControl<T>.observe(
         action: DisplayableAction<T>
     ): Observer<DisplayableControl.Action<T>> = this@observe.action.observe {

reactiveviewmodel/src/main/java/com/alexdeww/reactiveviewmodel/core/common/RvmComponent.kt

@@ -1,6 +1,7 @@
 package com.alexdeww.reactiveviewmodel.core.common
 
 import com.alexdeww.reactiveviewmodel.core.property.Action
+import com.alexdeww.reactiveviewmodel.core.property.ConfirmationEvent
 import com.alexdeww.reactiveviewmodel.core.property.Event
 import com.alexdeww.reactiveviewmodel.core.property.State
 import io.reactivex.rxjava3.core.Observable
@@ -30,4 +31,12 @@ interface RvmComponent {
 
     val <T : Any> Event<T>.observable: Observable<T> get() = this.observable
 
+    fun <T : Any> ConfirmationEvent<T>.call(value: T) = this.consumer.accept(value)
+
+    fun ConfirmationEvent<Unit>.call() = this.consumer.accept(Unit)
+
+    val <T : Any> ConfirmationEvent<T>.consumer: Consumer<T> get() = this.consumer
+
+    val <T : Any> ConfirmationEvent<T>.observable: Observable<T> get() = this.observable
+
 }

reactiveviewmodel/src/main/java/com/alexdeww/reactiveviewmodel/core/property/ConfirmationEvent.kt

@@ -0,0 +1,87 @@
+package com.alexdeww.reactiveviewmodel.core.property
+
+import androidx.annotation.MainThread
+import androidx.collection.ArraySet
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MediatorLiveData
+import androidx.lifecycle.Observer
+import com.alexdeww.reactiveviewmodel.core.property.ConfirmationEvent.ObserverWrapper
+import io.reactivex.rxjava3.core.Flowable
+import io.reactivex.rxjava3.core.Observable
+import io.reactivex.rxjava3.functions.Consumer
+
+class ConfirmationEvent<T : Any> internal constructor(debounceInterval: Long? = null) {
+
+    private sealed class EventType {
+        data class Pending(val data: Any) : EventType()
+        object Confirmed : EventType()
+    }
+
+    private val eventState = State<EventType>(EventType.Confirmed, debounceInterval)
+
+    internal val consumer: Consumer<T> = Consumer {
+        eventState.consumer.accept(EventType.Pending(it))
+    }
+
+    @Suppress("UNCHECKED_CAST")
+    internal val observable: Observable<T> = eventState.observable
+        .ofType(EventType.Pending::class.java)
+        .map { it.data as T }
+
+    val liveData: LiveData<T> by lazy { ConfirmationEventLiveData() }
+    val viewFlowable: Flowable<T> by lazy { observable.toViewFlowable() }
+    val isConfirmed: Boolean get() = eventState.value === EventType.Confirmed
+
+    fun confirm() {
+        eventState.consumer.accept(EventType.Confirmed)
+    }
+
+    private inner class ConfirmationEventLiveData : MediatorLiveData<T>() {
+
+        private val observers = ArraySet<ConfirmationEvent.ObserverWrapper<T>>()
+
+        @MainThread
+        override fun observe(owner: LifecycleOwner, observer: Observer<in T>) {
+            val wrapper = ObserverWrapper(observer)
+            observers.add(wrapper)
+            super.observe(owner, wrapper)
+        }
+
+        @MainThread
+        override fun removeObserver(observer: Observer<in T>) {
+            if (observers.remove(observer as Observer<*>)) {
+                super.removeObserver(observer)
+                return
+            }
+
+            val iterator = observers.iterator()
+            while (iterator.hasNext()) {
+                val wrapper = iterator.next()
+                if (wrapper.observer == observer) {
+                    iterator.remove()
+                    super.removeObserver(observer)
+                    break
+                }
+            }
+        }
+
+        @Suppress("UNCHECKED_CAST")
+        override fun onActive() {
+            super.onActive()
+            addSource(eventState.liveData) { value = (it as? EventType.Pending)?.data as T }
+        }
+
+        override fun onInactive() {
+            removeSource(eventState.liveData)
+            super.onInactive()
+        }
+    }
+
+    private class ObserverWrapper<T>(val observer: Observer<in T>) : Observer<T> {
+        override fun onChanged(t: T?) {
+            if (t != null) observer.onChanged(t)
+        }
+    }
+
+}