From e9acc031870b8a1ea5f88ea330e0989d6d4f003c Mon Sep 17 00:00:00 2001
From: ABDELMAJID ID ALI <abdelmajid.idali@adria-bt.com>
Date: Tue, 2 May 2023 11:51:17 +0100
Subject: [PATCH] - Add empty extension function to create empty PagingData

---
 .../com/kuuurt/paging/multiplatform/PagingData.kt      |  7 ++++++-
 .../com/kuuurt/paging/multiplatform/PagingData.kt      | 10 ++++++++--
 .../kuuurt/paging/multiplatform/sample/MainActivity.kt |  3 +++
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/paging/src/commonMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt b/paging/src/commonMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt
index b5a37ff..e8f7ae8 100644
--- a/paging/src/commonMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt
+++ b/paging/src/commonMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt
@@ -8,7 +8,12 @@ package com.kuuurt.paging.multiplatform
  * @since 06/11/2020
  */
 
-expect class PagingData<T : Any>
+expect class PagingData<T : Any> {
+
+    companion object {
+        fun <T : Any> empty(): PagingData<T>
+    }
+}
 
 expect suspend fun <T : Any> PagingData<T>.filter(predicate: suspend (T) -> Boolean): PagingData<T>
 
diff --git a/paging/src/iosMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt b/paging/src/iosMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt
index 1fffd4a..76fc478 100644
--- a/paging/src/iosMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt
+++ b/paging/src/iosMain/kotlin/com/kuuurt/paging/multiplatform/PagingData.kt
@@ -7,9 +7,15 @@ package com.kuuurt.paging.multiplatform
  * @since 06/11/2020
  */
 
-actual class PagingData<T : Any> internal constructor(items: List<T>) : List<T> by items
+actual class PagingData<T : Any> internal constructor(items: List<T>) : List<T> by items {
+    actual companion object {
+        actual fun <T : Any> empty(): PagingData<T> {
+            return PagingData(emptyList())
+        }
+    }
+}
 
-internal fun <T: Any> List<T>.toPagingData(): PagingData<T> =
+internal fun <T : Any> List<T>.toPagingData(): PagingData<T> =
     PagingData(this)
 
 actual suspend fun <T : Any> PagingData<T>.filter(predicate: suspend (T) -> Boolean): PagingData<T> {
diff --git a/sample/android/src/main/java/com/kuuurt/paging/multiplatform/sample/MainActivity.kt b/sample/android/src/main/java/com/kuuurt/paging/multiplatform/sample/MainActivity.kt
index 732d85b..7851989 100644
--- a/sample/android/src/main/java/com/kuuurt/paging/multiplatform/sample/MainActivity.kt
+++ b/sample/android/src/main/java/com/kuuurt/paging/multiplatform/sample/MainActivity.kt
@@ -4,11 +4,13 @@ import android.os.Bundle
 import android.util.Log
 import androidx.appcompat.app.AppCompatActivity
 import androidx.lifecycle.lifecycleScope
+import androidx.paging.PagingData
 import androidx.recyclerview.widget.RecyclerView
 import com.kuuurt.paging.sample.multiplatform.library.MainViewModel
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
+import kotlinx.coroutines.flow.onEmpty
 
 /**
  * Copyright 2020, Kurt Renzo Acosta, All rights reserved.
@@ -41,6 +43,7 @@ class MainActivity : AppCompatActivity(R.layout.activity_main) {
             .launchIn(lifecycleScope)
 
         viewModel.pagingData
+            .onEmpty { testAdapter.submitData(PagingData.empty()) }
             .onEach { testAdapter.submitData(it) }
             .launchIn(lifecycleScope)
     }