Fix browse scrolling back to top

same with extensions + migrations

app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferencesHelper.kt

@@ -151,7 +151,7 @@ class PreferencesHelper(val context: Context) {
 
     fun autoUpdateTrack() = prefs.getBoolean(Keys.autoUpdateTrack, true)
 
-    fun lastUsedCatalogueSource() = rxPrefs.getLong(Keys.lastUsedCatalogueSource, -1)
+    fun lastUsedCatalogueSource() = flowPrefs.getLong(Keys.lastUsedCatalogueSource, -1)
 
     fun lastUsedCategory() = rxPrefs.getInteger(Keys.lastUsedCategory, 0)
 

app/src/main/java/eu/kanade/tachiyomi/ui/extension/ExtensionBottomSheet.kt

@@ -6,6 +6,9 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import android.widget.LinearLayout
+import androidx.core.view.get
+import androidx.recyclerview.widget.RecyclerView
+import androidx.viewpager.widget.PagerAdapter.POSITION_NONE
 import com.google.android.material.bottomsheet.BottomSheetBehavior
 import com.google.android.material.tabs.TabLayout
 import eu.davidea.flexibleadapter.FlexibleAdapter
@@ -28,9 +31,7 @@ import eu.kanade.tachiyomi.util.view.collapse
 import eu.kanade.tachiyomi.util.view.doOnApplyWindowInsets
 import eu.kanade.tachiyomi.util.view.expand
 import eu.kanade.tachiyomi.util.view.isExpanded
-import eu.kanade.tachiyomi.util.view.updatePaddingRelative
 import eu.kanade.tachiyomi.util.view.withFadeTransaction
-import eu.kanade.tachiyomi.widget.ViewPagerAdapter
 import uy.kohesive.injekt.Injekt
 import uy.kohesive.injekt.api.get
 
@@ -49,9 +50,12 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
     /**
      * Adapter containing the list of extensions
      */
-    private var adapter: FlexibleAdapter<IFlexible<*>>? = null
+    private var adapter: ExtensionAdapter? = null
     private var migAdapter: FlexibleAdapter<IFlexible<*>>? = null
 
+    val adapters
+        get() = listOf(adapter, migAdapter)
+
     val presenter = ExtensionBottomPresenter(this)
 
     private var extensions: List<ExtensionItem> = emptyList()
@@ -59,9 +63,12 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
     private lateinit var binding: ExtensionsBottomSheetBinding
 
     lateinit var controller: BrowseController
+    var boundViews = arrayListOf<RecyclerWithScrollerView>()
 
-    val extensionFrameLayout = RecyclerWithScrollerBinding.inflate(LayoutInflater.from(context))
+    val extensionFrameLayout: RecyclerWithScrollerView? 
-    val migrationFrameLayout = RecyclerWithScrollerBinding.inflate(LayoutInflater.from(context))
+        get() = binding.pager.findViewWithTag("TabbedRecycler0") as? RecyclerWithScrollerView
+    val migrationFrameLayout: RecyclerWithScrollerView?
+        get() = binding.pager.findViewWithTag("TabbedRecycler1") as? RecyclerWithScrollerView
 
     override fun onFinishInflate() {
         super.onFinishInflate()
@@ -71,29 +78,22 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
     fun onCreate(controller: BrowseController) {
         // Initialize adapter, scroll listener and recycler views
         adapter = ExtensionAdapter(this)
-        migAdapter = ExtensionAdapter(this)
+        adapter?.stateRestorationPolicy = RecyclerView.Adapter.StateRestorationPolicy.PREVENT_WHEN_EMPTY
+        if (migAdapter == null) {
+            migAdapter = SourceAdapter(this)
+        }
+        migAdapter?.stateRestorationPolicy = RecyclerView.Adapter.StateRestorationPolicy.PREVENT_WHEN_EMPTY
         sheetBehavior = BottomSheetBehavior.from(this)
         // Create recycler and set adapter.
-        val extRecyler = extensionFrameLayout.recycler
-        val migRecyler = migrationFrameLayout.recycler
 
-        extRecyler.layoutManager = androidx.recyclerview.widget.LinearLayoutManager(context)
+        binding.pager.adapter = TabbedSheetAdapter()
-        extRecyler.adapter = adapter
+        binding.tabs.setupWithViewPager(binding.pager)
-        extRecyler.setHasFixedSize(true)
-        extRecyler.addItemDecoration(ExtensionDividerItemDecoration(context))
-
-        migRecyler.layoutManager = androidx.recyclerview.widget.LinearLayoutManager(context)
-        migRecyler.setHasFixedSize(true)
-
-        adapter?.fastScroller = extensionFrameLayout.fastScroller
         this.controller = controller
         binding.pager.doOnApplyWindowInsets { _, _, _ ->
             val bottomBar = controller.activityBinding?.bottomNav
-            extRecyler.updatePaddingRelative(bottom = bottomBar?.height ?: 0)
+            // extRecyler?.updatePaddingRelative(bottom = bottomBar?.height ?: 0)
-            migRecyler.updatePaddingRelative(bottom = bottomBar?.height ?: 0)
+            // migRecyler?.updatePaddingRelative(bottom = bottomBar?.height ?: 0)
         }
-        binding.pager.adapter = TabbedSheetAdapter()
-        binding.tabs.setupWithViewPager(binding.pager)
         binding.tabs.addOnTabSelectedListener(object : TabLayout.OnTabSelectedListener {
             override fun onTabSelected(tab: TabLayout.Tab?) {
                 if (canExpand) {
@@ -103,18 +103,18 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
                 when (tab?.position) {
                     0 -> extensionFrameLayout
                     else -> migrationFrameLayout
-                }.recycler.isNestedScrollingEnabled = true
+                }?.binding?.recycler?.isNestedScrollingEnabled = true
                 when (tab?.position) {
                     0 -> extensionFrameLayout
                     else -> migrationFrameLayout
-                }.recycler.requestLayout()
+                }?.binding?.recycler?.requestLayout()
             }
 
             override fun onTabUnselected(tab: TabLayout.Tab?) {
                 when (tab?.position) {
                     0 -> extensionFrameLayout
                     else -> migrationFrameLayout
-                }.recycler.isNestedScrollingEnabled = false
+                }?.binding?.recycler?.isNestedScrollingEnabled = false
                 if (tab?.position == 1) {
                     presenter.deselectSource()
                 }
@@ -125,7 +125,7 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
                 when (tab?.position) {
                     0 -> extensionFrameLayout
                     else -> migrationFrameLayout
-                }.recycler.isNestedScrollingEnabled = true
+                }?.binding?.recycler?.isNestedScrollingEnabled = true
             }
         })
         presenter.onCreate()
@@ -144,7 +144,7 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
 
     fun updatedNestedRecyclers() {
         listOf(extensionFrameLayout, migrationFrameLayout).forEachIndexed { index, recyclerWithScrollerBinding ->
-            recyclerWithScrollerBinding.recycler.isNestedScrollingEnabled = binding.pager.currentItem == index
+            recyclerWithScrollerBinding?.binding?.recycler?.isNestedScrollingEnabled = binding.pager.currentItem == index
         }
     }
 
@@ -162,7 +162,7 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
     }
 
     override fun onButtonClick(position: Int) {
-        val extension = (adapter?.getItem(position) as? ExtensionItem)?.extension ?: return
+        val extension = (migAdapter?.getItem(position) as? ExtensionItem)?.extension ?: return
         when (extension) {
             is Extension.Installed -> {
                 if (!extension.hasUpdate) {
@@ -249,21 +249,19 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
     }
 
     fun setMigrationSources(sources: List<SourceItem>) {
-        val migRecyler = migrationFrameLayout.recycler
         if (migAdapter !is SourceAdapter) {
             migAdapter = SourceAdapter(this)
-            migRecyler.adapter = migAdapter
+            migrationFrameLayout?.onBind(migAdapter!!)
-            migAdapter?.fastScroller = migrationFrameLayout.fastScroller
+            migAdapter?.stateRestorationPolicy = RecyclerView.Adapter.StateRestorationPolicy.PREVENT_WHEN_EMPTY
         }
         migAdapter?.updateDataSet(sources, true)
     }
 
     fun setMigrationManga(manga: List<MangaItem>?) {
-        val migRecyler = migrationFrameLayout.recycler
         if (migAdapter !is MangaAdapter) {
             migAdapter = MangaAdapter(this)
-            migRecyler.adapter = migAdapter
+            migrationFrameLayout?.onBind(migAdapter!!)
-            migAdapter?.fastScroller = migrationFrameLayout.fastScroller
+            migAdapter?.stateRestorationPolicy = RecyclerView.Adapter.StateRestorationPolicy.PREVENT_WHEN_EMPTY
         }
         migAdapter?.updateDataSet(manga, true)
     }
@@ -301,14 +299,7 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
         presenter.uninstallExtension(pkgName)
     }
 
-    private inner class TabbedSheetAdapter : ViewPagerAdapter() {
+    private inner class TabbedSheetAdapter : RecyclerViewPagerAdapter() {
-
-        override fun createView(container: ViewGroup, position: Int): View {
-            return when (position) {
-                0 -> extensionFrameLayout.root
-                else -> migrationFrameLayout.root
-            }
-        }
 
         override fun getCount(): Int {
             return 2
@@ -322,5 +313,60 @@ class ExtensionBottomSheet @JvmOverloads constructor(context: Context, attrs: At
                 }
             )
         }
+
+        /**
+         * Creates a new view for this adapter.
+         *
+         * @return a new view.
+         */
+        override fun createView(container: ViewGroup): View {
+            val binding = RecyclerWithScrollerBinding.inflate(LayoutInflater.from(container.context), container, false)
+            val view: RecyclerWithScrollerView = binding.root
+            view.setUp(this@ExtensionBottomSheet, binding)
+            return view
+        }
+
+        /**
+         * Binds a view with a position.
+         *
+         * @param view the view to bind.
+         * @param position the position in the adapter.
+         */
+        override fun bindView(view: View, position: Int) {
+            (view as RecyclerWithScrollerView).onBind(adapters[position]!!)
+            view.setTag("TabbedRecycler$position")
+            boundViews.add(view)
+        }
+
+        /**
+         * Recycles a view.
+         *
+         * @param view the view to recycle.
+         * @param position the position in the adapter.
+         */
+        override fun recycleView(view: View, position: Int) {
+            // (view as RecyclerWithScrollerView).onRecycle()
+            boundViews.remove(view)
+        }
+
+        /**
+         * Returns the position of the view.
+         */
+        override fun getItemPosition(obj: Any): Int {
+            val view = (obj as? RecyclerWithScrollerView) ?: return POSITION_NONE
+            val index = adapters.indexOfFirst { it == view.binding?.recycler?.adapter }
+            return if (index == -1) POSITION_NONE else index
+        }
+
+        /**
+         * Called when the view of this adapter is being destroyed.
+         */
+        fun onDestroy() {
+            /*for (view in boundViews) {
+                if (view is LibraryCategoryView) {
+                    view.onDestroy()
+                }
+            }*/
+        }
     }
 }

app/src/main/java/eu/kanade/tachiyomi/ui/extension/RecyclerViewPagerAdapter.kt

@@ -0,0 +1,34 @@
+package eu.kanade.tachiyomi.ui.extension
+
+import android.view.View
+import android.view.ViewGroup
+import com.nightlynexus.viewstatepageradapter.ViewStatePagerAdapter
+import java.util.Stack
+
+abstract class RecyclerViewPagerAdapter : ViewStatePagerAdapter() {
+
+    private val pool = Stack<View>()
+
+    var recycle = true
+        set(value) {
+            if (!value) pool.clear()
+            field = value
+        }
+
+    protected abstract fun createView(container: ViewGroup): View
+
+    protected abstract fun bindView(view: View, position: Int)
+
+    protected open fun recycleView(view: View, position: Int) {}
+
+    override fun createView(container: ViewGroup, position: Int): View {
+        val view = if (pool.isNotEmpty()) pool.pop() else createView(container)
+        bindView(view, position)
+        return view
+    }
+
+    override fun destroyView(container: ViewGroup, position: Int, view: View) {
+        recycleView(view, position)
+        if (recycle) pool.push(view)
+    }
+}

app/src/main/java/eu/kanade/tachiyomi/ui/extension/RecyclerWithScrollerView.kt

@@ -0,0 +1,25 @@
+package eu.kanade.tachiyomi.ui.extension
+
+import android.content.Context
+import android.util.AttributeSet
+import android.widget.FrameLayout
+import eu.davidea.flexibleadapter.FlexibleAdapter
+import eu.davidea.flexibleadapter.items.IFlexible
+import eu.kanade.tachiyomi.databinding.RecyclerWithScrollerBinding
+
+class RecyclerWithScrollerView @JvmOverloads constructor(context: Context, attrs: AttributeSet? = null) :
+    FrameLayout(context, attrs) {
+
+    var binding: RecyclerWithScrollerBinding? = null
+    fun setUp(sheet: ExtensionBottomSheet, binding: RecyclerWithScrollerBinding) {
+        binding.recycler.layoutManager = androidx.recyclerview.widget.LinearLayoutManager(context)
+        binding.recycler.setHasFixedSize(true)
+        binding.recycler.addItemDecoration(ExtensionDividerItemDecoration(context))
+        this.binding = binding
+    }
+
+    fun onBind(adapter: FlexibleAdapter<IFlexible<*>>) {
+        binding?.recycler?.adapter = adapter
+        adapter.fastScroller = binding?.fastScroller
+    }
+}

app/src/main/java/eu/kanade/tachiyomi/ui/recents/RecentsPresenter.kt

@@ -367,7 +367,7 @@ class RecentsPresenter(
         getRecents()
     }
 
-    companion object {
+    private companion object {
         var lastRecents: List<RecentMangaItem>? = null
     }
 }

app/src/main/java/eu/kanade/tachiyomi/ui/source/BrowseController.kt

@@ -13,6 +13,7 @@ import android.view.ViewGroup
 import androidx.appcompat.widget.SearchView
 import androidx.core.content.ContextCompat
 import androidx.core.graphics.ColorUtils
+import androidx.recyclerview.widget.RecyclerView
 import com.bluelinelabs.conductor.ControllerChangeHandler
 import com.bluelinelabs.conductor.ControllerChangeType
 import com.bluelinelabs.conductor.RouterTransaction
@@ -27,7 +28,7 @@ import eu.kanade.tachiyomi.data.preference.getOrDefault
 import eu.kanade.tachiyomi.databinding.BrowseControllerBinding
 import eu.kanade.tachiyomi.source.CatalogueSource
 import eu.kanade.tachiyomi.source.Source
-import eu.kanade.tachiyomi.ui.base.controller.NucleusController
+import eu.kanade.tachiyomi.ui.base.controller.BaseController
 import eu.kanade.tachiyomi.ui.extension.SettingsExtensionsController
 import eu.kanade.tachiyomi.ui.main.BottomSheetController
 import eu.kanade.tachiyomi.ui.main.MainActivity
@@ -66,7 +67,7 @@ import kotlin.math.min
  * [SourceAdapter.OnLatestClickListener] call function data on latest item click
  */
 class BrowseController :
-    NucleusController<BrowseControllerBinding, SourcePresenter>(),
+    BaseController<BrowseControllerBinding>(),
     FlexibleAdapter.OnItemClickListener,
     SourceAdapter.SourceListener,
     RootSearchInterface,
@@ -109,9 +110,7 @@ class BrowseController :
         } else view?.context?.getString(R.string.browse)
     }
 
-    override fun createPresenter(): SourcePresenter {
+    val presenter = SourcePresenter(this)
-        return SourcePresenter()
-    }
 
     override fun createBinding(inflater: LayoutInflater) = BrowseControllerBinding.inflate(inflater)
 
@@ -119,29 +118,34 @@ class BrowseController :
         super.onViewCreated(view)
 
         adapter = SourceAdapter(this)
+        // Create binding.sourceRecycler and set adapter.
+        binding.sourceRecycler.layoutManager = androidx.recyclerview.widget.LinearLayoutManager(view.context)
 
-        // Create binding.recycler and set adapter.
+        binding.sourceRecycler.adapter = adapter
-        binding.recycler.layoutManager = androidx.recyclerview.widget.LinearLayoutManager(view.context)
-        binding.recycler.adapter = adapter
         adapter?.isSwipeEnabled = true
-        // binding.recycler.addItemDecoration(SourceDividerItemDecoration(view.context))
+        adapter?.stateRestorationPolicy = RecyclerView.Adapter.StateRestorationPolicy.PREVENT_WHEN_EMPTY
+        // binding.sourceRecycler.addItemDecoration(SourceDividerItemDecoration(view.context))
         val attrsArray = intArrayOf(android.R.attr.actionBarSize)
         val array = view.context.obtainStyledAttributes(attrsArray)
         val appBarHeight = array.getDimensionPixelSize(0, 0)
         array.recycle()
         scrollViewWith(
-            binding.recycler,
+            binding.sourceRecycler,
             afterInsets = {
                 headerHeight = it.systemWindowInsetTop + appBarHeight
-                binding.recycler.updatePaddingRelative(bottom = activityBinding?.bottomNav?.height ?: 0)
+                binding.sourceRecycler.updatePaddingRelative(bottom = activityBinding?.bottomNav?.height ?: 0)
             },
             onBottomNavUpdate = {
                 setBottomPadding()
             }
         )
 
-        binding.recycler.post {
+        binding.sourceRecycler.post {
             setBottomSheetTabs(if (binding.bottomSheet.root.sheetBehavior.isCollapsed()) 0f else 1f)
+            activityBinding?.appBar?.elevation = min(
+                if (binding.bottomSheet.root.sheetBehavior.isCollapsed()) 0f else 1f * 15f,
+                if (binding.sourceRecycler.canScrollVertically(-1)) 15f else 0f
+            )
         }
 
         requestPermissionsSafe(arrayOf(WRITE_EXTERNAL_STORAGE), 301)
@@ -154,7 +158,7 @@ class BrowseController :
                     binding.shadow2.alpha = (1 - max(0f, progress)) * 0.25f
                     activityBinding?.appBar?.elevation = min(
                         (1f - progress) * 15f,
-                        if (binding.recycler.canScrollVertically(-1)) 15f else 0f
+                        if (binding.sourceRecycler.canScrollVertically(-1)) 15f else 0f
                     )
                     activityBinding?.appBar?.y = max(activityBinding!!.appBar.y, -headerHeight * (1 - progress))
                     val oldShow = showingExtensions
@@ -200,6 +204,10 @@ class BrowseController :
         if (showingExtensions) {
             binding.bottomSheet.root.sheetBehavior?.expand()
         }
+        presenter.onCreate()
+        if (presenter.sourceItems.isNotEmpty()) {
+            setSources(presenter.sourceItems, presenter.lastUsedItem)
+        }
     }
 
     fun updateTitleAndMenu() {
@@ -256,10 +264,10 @@ class BrowseController :
         )
         binding.shadow2.translationY = pad
         binding.bottomSheet.root.sheetBehavior?.peekHeight = 58.spToPx + padding
-        binding.bottomSheet.root.extensionFrameLayout.fastScroller.updateLayoutParams<ViewGroup.MarginLayoutParams> {
+        binding.bottomSheet.root.extensionFrameLayout?.binding?.fastScroller?.updateLayoutParams<ViewGroup.MarginLayoutParams> {
             bottomMargin = -pad.toInt()
         }
-        binding.bottomSheet.root.migrationFrameLayout.fastScroller.updateLayoutParams<ViewGroup.MarginLayoutParams> {
+        binding.bottomSheet.root.migrationFrameLayout?.binding?.fastScroller?.updateLayoutParams<ViewGroup.MarginLayoutParams> {
             bottomMargin = -pad.toInt()
         }
     }
@@ -293,6 +301,11 @@ class BrowseController :
         super.onDestroyView(view)
     }
 
+    override fun onDestroy() {
+        super.onDestroy()
+        presenter.onDestroy()
+    }
+
     override fun onChangeStarted(handler: ControllerChangeHandler, type: ControllerChangeType) {
         super.onChangeStarted(handler, type)
         if (!type.isPush) {
@@ -305,7 +318,7 @@ class BrowseController :
             activityBinding?.appBar?.elevation =
                 when {
                     binding.bottomSheet.root.sheetBehavior.isExpanded() -> 0f
-                    binding.recycler.canScrollVertically(-1) -> 15f
+                    binding.sourceRecycler.canScrollVertically(-1) -> 15f
                     else -> 0f
                 }
         } else {
@@ -483,8 +496,9 @@ class BrowseController :
     /**
      * Called to update adapter containing sources.
      */
-    fun setSources(sources: List<IFlexible<*>>) {
+    fun setSources(sources: List<IFlexible<*>>, lastUsed: SourceItem?) {
-        adapter?.updateDataSet(sources)
+        adapter?.updateDataSet(sources, false)
+        setLastUsedSource(lastUsed)
     }
 
     /**

app/src/main/java/eu/kanade/tachiyomi/ui/source/SourcePresenter.kt

@@ -1,19 +1,20 @@
 package eu.kanade.tachiyomi.ui.source
 
-import android.os.Bundle
 import eu.kanade.tachiyomi.data.preference.PreferencesHelper
 import eu.kanade.tachiyomi.data.preference.getOrDefault
 import eu.kanade.tachiyomi.source.CatalogueSource
 import eu.kanade.tachiyomi.source.LocalSource
 import eu.kanade.tachiyomi.source.SourceManager
-import eu.kanade.tachiyomi.ui.base.presenter.BasePresenter
+import eu.kanade.tachiyomi.util.system.withUIContext
-import rx.Observable
+import kotlinx.coroutines.CoroutineScope
-import rx.Subscription
+import kotlinx.coroutines.Dispatchers
-import rx.android.schedulers.AndroidSchedulers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.flow.onEach
+import kotlinx.coroutines.launch
 import uy.kohesive.injekt.Injekt
 import uy.kohesive.injekt.api.get
 import java.util.TreeMap
-import java.util.concurrent.TimeUnit
 
 /**
  * Presenter of [BrowseController]
@@ -23,86 +24,102 @@ import java.util.concurrent.TimeUnit
  * @param preferences application preferences.
  */
 class SourcePresenter(
+    val controller: BrowseController,
     val sourceManager: SourceManager = Injekt.get(),
     private val preferences: PreferencesHelper = Injekt.get()
-) : BasePresenter<BrowseController>() {
+) {
 
+    private var scope = CoroutineScope(Job() + Dispatchers.Default)
     var sources = getEnabledSources()
 
-    /**
+    var sourceItems = emptyList<SourceItem>()
-     * Subscription for retrieving enabled sources.
+    var lastUsedItem: SourceItem? = null
-     */
-    private var sourceSubscription: Subscription? = null
-    private var lastUsedSubscription: Subscription? = null
 
-    override fun onCreate(savedState: Bundle?) {
+    var lastUsedJob: Job? = null
-        super.onCreate(savedState)
+
+    fun onCreate() {
+        if (lastSources != null) {
+            if (sourceItems.isEmpty()) {
+                sourceItems = lastSources ?: emptyList()
+            }
+            lastUsedItem = lastUsedItemRem
+            lastSources = null
+            lastUsedItemRem = null
+        }
 
         // Load enabled and last used sources
         loadSources()
-        loadLastUsedSource()
     }
 
     /**
      * Unsubscribe and create a new subscription to fetch enabled sources.
      */
     private fun loadSources() {
-        sourceSubscription?.unsubscribe()
+        scope.launch {
+            val pinnedSources = mutableListOf<SourceItem>()
+            val pinnedCatalogues = preferences.pinnedCatalogues().getOrDefault()
 
-        val pinnedSources = mutableListOf<SourceItem>()
+            val map = TreeMap<String, MutableList<CatalogueSource>> { d1, d2 ->
-        val pinnedCatalogues = preferences.pinnedCatalogues().getOrDefault()
+                // Catalogues without a lang defined will be placed at the end
-
+                when {
-        val map = TreeMap<String, MutableList<CatalogueSource>> { d1, d2 ->
+                    d1 == "" && d2 != "" -> 1
-            // Catalogues without a lang defined will be placed at the end
+                    d2 == "" && d1 != "" -> -1
-            when {
+                    else -> d1.compareTo(d2)
-                d1 == "" && d2 != "" -> 1
-                d2 == "" && d1 != "" -> -1
-                else -> d1.compareTo(d2)
-            }
-        }
-        val byLang = sources.groupByTo(map, { it.lang })
-        var sourceItems = byLang.flatMap {
-            val langItem = LangItem(it.key)
-            it.value.map { source ->
-                val isPinned = source.id.toString() in pinnedCatalogues
-                if (source.id.toString() in pinnedCatalogues) {
-                    pinnedSources.add(SourceItem(source, LangItem(PINNED_KEY)))
                 }
+            }
+            val byLang = sources.groupByTo(map, { it.lang })
+            sourceItems = byLang.flatMap {
+                val langItem = LangItem(it.key)
+                it.value.map { source ->
+                    val isPinned = source.id.toString() in pinnedCatalogues
+                    if (source.id.toString() in pinnedCatalogues) {
+                        pinnedSources.add(SourceItem(source, LangItem(PINNED_KEY)))
+                    }
 
-                SourceItem(source, langItem, isPinned)
+                    SourceItem(source, langItem, isPinned)
+                }
+            }
+
+            if (pinnedSources.isNotEmpty()) {
+                sourceItems = pinnedSources + sourceItems
+            }
+
+            lastUsedItem = getLastUsedSource(preferences.lastUsedCatalogueSource().get())
+            withUIContext {
+                controller.setSources(sourceItems, lastUsedItem)
+                loadLastUsedSource()
             }
         }
-
-        if (pinnedSources.isNotEmpty()) {
-            sourceItems = pinnedSources + sourceItems
-        }
-
-        sourceSubscription = Observable.just(sourceItems)
-            .subscribeLatestCache(BrowseController::setSources)
     }
 
     private fun loadLastUsedSource() {
-        lastUsedSubscription?.unsubscribe()
+        lastUsedJob?.cancel()
-        val sharedObs = preferences.lastUsedCatalogueSource().asObservable().share()
+        lastUsedJob = preferences.lastUsedCatalogueSource().asFlow()
+            .onEach {
+                lastUsedItem = getLastUsedSource(it)
+                withUIContext {
+                    controller.setLastUsedSource(lastUsedItem)
+                }
+            }.launchIn(scope)
+    }
 
-        // Emit the first item immediately but delay subsequent emissions by 500ms.
+    private fun getLastUsedSource(value: Long): SourceItem? {
-        lastUsedSubscription = Observable.merge(
+        return (sourceManager.get(value) as? CatalogueSource)?.let { source ->
-            sharedObs.take(1),
+            val pinnedCatalogues = preferences.pinnedCatalogues().getOrDefault()
-            sharedObs.skip(1).delay(500, TimeUnit.MILLISECONDS, AndroidSchedulers.mainThread())
+            val isPinned = source.id.toString() in pinnedCatalogues
-        ).distinctUntilChanged().map {
+            if (isPinned) null
-            (sourceManager.get(it) as? CatalogueSource)?.let { source ->
+            else SourceItem(source, null, isPinned)
-                val pinnedCatalogues = preferences.pinnedCatalogues().getOrDefault()
+        }
-                val isPinned = source.id.toString() in pinnedCatalogues
-                if (isPinned) null
-                else SourceItem(source, null, isPinned)
-            }
-        }.subscribeLatestCache(BrowseController::setLastUsedSource)
     }
 
     fun updateSources() {
         sources = getEnabledSources()
         loadSources()
-        loadLastUsedSource()
+    }
+
+    fun onDestroy() {
+        lastSources = sourceItems
+        lastUsedItemRem = lastUsedItem
     }
 
     /**
@@ -124,5 +141,8 @@ class SourcePresenter(
     companion object {
         const val PINNED_KEY = "pinned"
         const val LAST_USED_KEY = "last_used"
+
+        private var lastSources: List<SourceItem>? = null
+        private var lastUsedItemRem: SourceItem? = null
     }
 }

app/src/main/res/layout/browse_controller.xml

@@ -3,6 +3,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
+    android:id="@+id/browse_layout"
     xmlns:app="http://schemas.android.com/apk/res-auto">
 
     <FrameLayout
@@ -12,7 +13,7 @@
         android:background="?android:attr/colorBackground">
 
         <androidx.recyclerview.widget.RecyclerView
-            android:id="@+id/recycler"
+            android:id="@+id/source_recycler"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:clipToPadding="false"

app/src/main/res/layout/recycler_with_scroller.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<eu.kanade.tachiyomi.ui.extension.RecyclerWithScrollerView xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/recycler_layout"
@@ -21,4 +21,4 @@
         android:layout_height="match_parent"
         app:fastScrollerBubbleEnabled="false" />
 
-</FrameLayout>
+</eu.kanade.tachiyomi.ui.extension.RecyclerWithScrollerView>