From d74d7c62bae3a865a6c617876e71c0282a423a35 Mon Sep 17 00:00:00 2001
From: Bnyro <bnyro@tutanota.com>
Date: Tue, 23 Jul 2024 17:58:53 +0200
Subject: [PATCH] fix: scroll state of trends not preserved

---
 .../libretube/ui/fragments/TrendsFragment.kt   | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/app/src/main/java/com/github/libretube/ui/fragments/TrendsFragment.kt b/app/src/main/java/com/github/libretube/ui/fragments/TrendsFragment.kt
index c61377044..fd1c878e1 100644
--- a/app/src/main/java/com/github/libretube/ui/fragments/TrendsFragment.kt
+++ b/app/src/main/java/com/github/libretube/ui/fragments/TrendsFragment.kt
@@ -1,14 +1,14 @@
 package com.github.libretube.ui.fragments
 
 import android.content.Intent
+import android.content.res.Configuration
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import androidx.core.view.isGone
 import androidx.fragment.app.activityViewModels
-import androidx.lifecycle.DefaultLifecycleObserver
-import androidx.lifecycle.LifecycleOwner
+import androidx.recyclerview.widget.RecyclerView
 import com.github.libretube.R
 import com.github.libretube.databinding.FragmentTrendsBinding
 import com.github.libretube.ui.activities.SettingsActivity
@@ -41,8 +41,9 @@ class TrendsFragment : DynamicLayoutManagerFragment() {
         viewModel.trendingVideos.observe(viewLifecycleOwner) { videos ->
             if (videos == null) return@observe
 
-            binding.recview.layoutManager?.onRestoreInstanceState(viewModel.recyclerViewState)
             binding.recview.adapter = VideosAdapter(videos.toMutableList())
+            binding.recview.layoutManager?.onRestoreInstanceState(viewModel.recyclerViewState)
+
             binding.homeRefresh.isRefreshing = false
             binding.progressBar.isGone = true
 
@@ -61,8 +62,9 @@ class TrendsFragment : DynamicLayoutManagerFragment() {
             viewModel.fetchTrending(requireContext())
         }
 
-        viewLifecycleOwner.lifecycle.addObserver(object : DefaultLifecycleObserver {
-            override fun onDestroy(owner: LifecycleOwner) {
+        binding.recview.addOnScrollListener(object : RecyclerView.OnScrollListener() {
+            override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
+                super.onScrollStateChanged(recyclerView, newState)
                 viewModel.recyclerViewState = _binding?.recview?.layoutManager?.onSaveInstanceState()
             }
         })
@@ -70,6 +72,12 @@ class TrendsFragment : DynamicLayoutManagerFragment() {
         viewModel.fetchTrending(requireContext())
     }
 
+    override fun onConfigurationChanged(newConfig: Configuration) {
+        super.onConfigurationChanged(newConfig)
+        // manually restore the recyclerview state due to https://github.com/material-components/material-components-android/issues/3473
+        binding.recview.layoutManager?.onRestoreInstanceState(viewModel.recyclerViewState)
+    }
+
     override fun onDestroyView() {
         super.onDestroyView()
         _binding = null