From 629884a396fc892d4b9d29261ccd9c7ad7a84a73 Mon Sep 17 00:00:00 2001
From: InsanusMokrassar <ovsyannikov.alexey95@gmail.com>
Date: Mon, 23 Nov 2020 00:36:37 +0600
Subject: [PATCH] update left items

---
 CHANGELOG.md                                         |  2 ++
 .../micro_utils/android/recyclerview/LeftItems.kt    | 12 +++++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b19566594cb..db3fc88a875 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 * `Versions`:
     * `Klock`: `1.12.1` -> `2.0.0`
+* `Commons`:
+    * Update left items functionality to include work with `GridLayoutManager`
 * `Repos`:
     * Add interface `VersionsRepo`
         * Add default realization of `VersionsRepo` named `StandardVersionsRepo` which use `StandardVersionsRepoProxy`
diff --git a/android/recyclerview/src/main/kotlin/dev/inmo/micro_utils/android/recyclerview/LeftItems.kt b/android/recyclerview/src/main/kotlin/dev/inmo/micro_utils/android/recyclerview/LeftItems.kt
index fc6d51b864e..d37fc919591 100644
--- a/android/recyclerview/src/main/kotlin/dev/inmo/micro_utils/android/recyclerview/LeftItems.kt
+++ b/android/recyclerview/src/main/kotlin/dev/inmo/micro_utils/android/recyclerview/LeftItems.kt
@@ -1,14 +1,20 @@
 package dev.inmo.micro_utils.android.recyclerview
 
-import androidx.recyclerview.widget.LinearLayoutManager
-import androidx.recyclerview.widget.RecyclerView
+import androidx.recyclerview.widget.*
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.flow.*
 
+@Suppress("NOTHING_TO_INLINE")
+private inline fun RecyclerView.LayoutManager.findLastVisibleItemPositionGetter(): (() -> Int)? = when (this) {
+    is LinearLayoutManager -> ::findLastVisibleItemPosition
+    is GridLayoutManager -> ::findLastVisibleItemPosition
+    else -> null
+}
+
 fun RecyclerView.lastVisibleItemFlow(
     completingScope: CoroutineScope
 ): Flow<Int> {
-    val lastVisibleElementFun: () -> Int = (layoutManager as? LinearLayoutManager) ?.let { it::findLastVisibleItemPosition } ?: error("Currently supported only linear layout manager")
+    val lastVisibleElementFun: () -> Int = layoutManager ?.findLastVisibleItemPositionGetter() ?: error("Currently supported only linear layout manager")
     val lastVisibleFlow = MutableStateFlow(lastVisibleElementFun())
     addOnScrollListener(
         object : RecyclerView.OnScrollListener() {