ui: create viewmodel for navigation

Create a ViewModel for the more complicated navigation pathways.

Normally, navigation was fragmented along a complicated stretch of
fragment hacks and DetailViewModel's navToItem attitbute, both of which
were not really that ideal. Dumpster them for a single, unified
viewmodel for the more complicated navigation situations. This removes
much of the duplicate navigation logic and is likely much more
maintainable for future situations.

app/src/main/java/org/oxycblt/auxio/MainFragment.kt

@@ -27,12 +27,16 @@ import androidx.activity.result.ActivityResultLauncher
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.fragment.app.activityViewModels
 import androidx.navigation.findNavController
+import androidx.navigation.fragment.findNavController
 import com.google.android.material.snackbar.Snackbar
 import org.oxycblt.auxio.databinding.FragmentMainBinding
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.music.MusicViewModel
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
+import org.oxycblt.auxio.ui.MainNavigationAction
+import org.oxycblt.auxio.ui.NavigationViewModel
 import org.oxycblt.auxio.ui.ViewBindingFragment
 import org.oxycblt.auxio.util.logW
 
@@ -45,13 +49,13 @@ import org.oxycblt.auxio.util.logW
  */
 class MainFragment : ViewBindingFragment<FragmentMainBinding>() {
     private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val navModel: NavigationViewModel by activityViewModels()
     private val musicModel: MusicViewModel by activityViewModels()
     private var callback: DynamicBackPressedCallback? = null
 
     override fun onCreateBinding(inflater: LayoutInflater) = FragmentMainBinding.inflate(inflater)
 
     override fun onBindingCreated(binding: FragmentMainBinding, savedInstanceState: Bundle?) {
-
         // --- UI SETUP ---
         // Build the permission launcher here as you can only do it in onCreateView/onCreate
         val permLauncher =
@@ -89,6 +93,9 @@ class MainFragment : ViewBindingFragment<FragmentMainBinding>() {
             handleLoaderResponse(response, permLauncher)
         }
 
+        navModel.mainNavigationAction.observe(viewLifecycleOwner, ::handleMainNavigation)
+        navModel.exploreNavigationItem.observe(viewLifecycleOwner, ::handleExploreNavigation)
+
         playbackModel.song.observe(viewLifecycleOwner, ::updateSong)
     }
 
@@ -146,6 +153,30 @@ class MainFragment : ViewBindingFragment<FragmentMainBinding>() {
         }
     }
 
+    private fun handleMainNavigation(action: MainNavigationAction?) {
+        if (action == null) return
+
+        val binding = requireBinding()
+        when (action) {
+            MainNavigationAction.EXPAND -> binding.bottomSheetLayout.expand()
+            MainNavigationAction.COLLAPSE -> binding.bottomSheetLayout.collapse()
+            MainNavigationAction.SETTINGS ->
+                findNavController().navigate(MainFragmentDirections.actionShowSettings())
+            MainNavigationAction.ABOUT ->
+                findNavController().navigate(MainFragmentDirections.actionShowAbout())
+            MainNavigationAction.QUEUE ->
+                findNavController().navigate(MainFragmentDirections.actionShowQueue())
+        }
+
+        navModel.finishMainNavigation()
+    }
+
+    private fun handleExploreNavigation(item: Music?) {
+        if (item != null) {
+            requireBinding().bottomSheetLayout.collapse()
+        }
+    }
+
     private fun updateSong(song: Song?) {
         val binding = requireBinding()
         if (song != null) {

app/src/main/java/org/oxycblt/auxio/accent/AccentAdapter.kt

@@ -33,15 +33,15 @@ import org.oxycblt.auxio.util.stateList
 
 /** An adapter that displays the accent palette. */
 class AccentAdapter(listener: Listener) :
-    MonoAdapter<Accent, AccentAdapter.Listener, NewAccentViewHolder>(listener) {
+    MonoAdapter<Accent, AccentAdapter.Listener, AccentViewHolder>(listener) {
     var selectedAccent: Accent? = null
         private set
-    private var selectedViewHolder: NewAccentViewHolder? = null
+    private var selectedViewHolder: AccentViewHolder? = null
 
     override val data = AccentData()
-    override val creator = NewAccentViewHolder.CREATOR
+    override val creator = AccentViewHolder.CREATOR
 
-    override fun onBindViewHolder(viewHolder: NewAccentViewHolder, position: Int) {
+    override fun onBindViewHolder(viewHolder: AccentViewHolder, position: Int) {
         super.onBindViewHolder(viewHolder, position)
 
         if (data.getItem(position) == selectedAccent) {
@@ -55,7 +55,7 @@ class AccentAdapter(listener: Listener) :
         if (accent == selectedAccent) return
         selectedAccent = accent
         selectedViewHolder?.setSelected(false)
-        selectedViewHolder = recycler.getViewHolderAt(accent.index) as NewAccentViewHolder?
+        selectedViewHolder = recycler.getViewHolderAt(accent.index) as AccentViewHolder?
         selectedViewHolder?.setSelected(true)
     }
 
@@ -69,7 +69,7 @@ class AccentAdapter(listener: Listener) :
     }
 }
 
-class NewAccentViewHolder private constructor(private val binding: ItemAccentBinding) :
+class AccentViewHolder private constructor(private val binding: ItemAccentBinding) :
     BindingViewHolder<Accent, AccentAdapter.Listener>(binding.root) {
 
     override fun bind(item: Accent, listener: AccentAdapter.Listener) {
@@ -79,9 +79,8 @@ class NewAccentViewHolder private constructor(private val binding: ItemAccentBin
             backgroundTintList = context.getColorSafe(item.primary).stateList
             contentDescription = context.getString(item.name)
             TooltipCompat.setTooltipText(this, contentDescription)
+            setOnClickListener { listener.onAccentSelected(item) }
         }
-
-        binding.accent.setOnClickListener { listener.onAccentSelected(item) }
     }
 
     fun setSelected(isSelected: Boolean) {
@@ -98,12 +97,12 @@ class NewAccentViewHolder private constructor(private val binding: ItemAccentBin
 
     companion object {
         val CREATOR =
-            object : Creator<NewAccentViewHolder> {
+            object : Creator<AccentViewHolder> {
                 override val viewType: Int
                     get() = throw UnsupportedOperationException()
 
                 override fun create(context: Context) =
-                    NewAccentViewHolder(ItemAccentBinding.inflate(context.inflater))
+                    AccentViewHolder(ItemAccentBinding.inflate(context.inflater))
             }
     }
 }

app/src/main/java/org/oxycblt/auxio/coil/Components.kt

@@ -24,6 +24,7 @@ import coil.decode.ImageSource
 import coil.fetch.FetchResult
 import coil.fetch.Fetcher
 import coil.fetch.SourceResult
+import coil.key.Keyer
 import coil.request.Options
 import coil.size.Size
 import kotlin.math.min
@@ -32,9 +33,22 @@ import okio.source
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.ui.Sort
 
+/** A basic keyer for music data. */
+class MusicKeyer : Keyer<Music> {
+    override fun key(data: Music, options: Options): String {
+        return if (data is Song) {
+            // Group up song covers with album covers for better caching
+            key(data.album, options)
+        } else {
+            "${data::class.simpleName}: ${data.id}"
+        }
+    }
+}
+
 /**
  * Fetcher that returns the album art for a given [Album] or [Song], depending on the factory used.
  * @author OxygenCobalt
@@ -128,7 +142,7 @@ private inline fun <T : Any, R : Any> Collection<T>.mapAtMost(
             break
         }
 
-        transform(item)?.let { out.add(it) }
+        transform(item)?.let(out::add)
     }
 
     return out

app/src/main/java/org/oxycblt/auxio/coil/MusicKeyer.kt

@@ -1,35 +0,0 @@
-/*
- * Copyright (c) 2022 Auxio Project
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
- 
-package org.oxycblt.auxio.coil
-
-import coil.key.Keyer
-import coil.request.Options
-import org.oxycblt.auxio.music.Music
-import org.oxycblt.auxio.music.Song
-
-/** A basic keyer for music data. */
-class MusicKeyer : Keyer<Music> {
-    override fun key(data: Music, options: Options): String {
-        return if (data is Song) {
-            // Group up song covers with album covers for better caching
-            key(data.album, options)
-        } else {
-            "${data::class.simpleName}: ${data.id}"
-        }
-    }
-}

app/src/main/java/org/oxycblt/auxio/coil/StyledImageView.kt

@@ -44,7 +44,10 @@ import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.settings.SettingsManager
 import org.oxycblt.auxio.util.getColorStateListSafe
 
-/** An [AppCompatImageView] that applies many of the stylistic choices thjat Auxio uses wi */
+/**
+ * An [AppCompatImageView] that applies many of the stylistic choices that Auxio uses regarding
+ * images.
+ */
 class StyledImageView
 @JvmOverloads
 constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr: Int = 0) :
@@ -85,6 +88,7 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
         super.onMeasure(widthMeasureSpec, heightMeasureSpec)
 
+        // Scale the image down to half-size
         imageMatrix =
             centerMatrix.apply {
                 reset()

app/src/main/java/org/oxycblt/auxio/detail/AlbumDetailFragment.kt

@@ -81,16 +81,9 @@ class AlbumDetailFragment : DetailFragment(), AlbumDetailAdapter.Listener {
 
         // -- VIEWMODEL SETUP ---
 
-        detailModel.albumData.observe(viewLifecycleOwner) { list ->
+        detailModel.albumData.observe(viewLifecycleOwner, detailAdapter.data::submitList)
-            detailAdapter.data.submitList(list)
+        navModel.exploreNavigationItem.observe(viewLifecycleOwner, ::handleNavigation)
-        }
+        playbackModel.song.observe(viewLifecycleOwner, ::updateSong)
-
-        detailModel.navToItem.observe(viewLifecycleOwner) { item ->
-            handleNavigation(item, detailAdapter)
-        }
-
-        updateSong(playbackModel.song.value, detailAdapter)
-        playbackModel.song.observe(viewLifecycleOwner) { song -> updateSong(song, detailAdapter) }
     }
 
     override fun onItemClick(item: Item) {
@@ -126,7 +119,7 @@ class AlbumDetailFragment : DetailFragment(), AlbumDetailAdapter.Listener {
                     unlikelyToBeNull(detailModel.currentAlbum.value).artist.id))
     }
 
-    private fun handleNavigation(item: Music?, adapter: AlbumDetailAdapter) {
+    private fun handleNavigation(item: Music?) {
         val binding = requireBinding()
         when (item) {
             // Songs should be scrolled to if the album matches, or a new detail
@@ -134,8 +127,8 @@ class AlbumDetailFragment : DetailFragment(), AlbumDetailAdapter.Listener {
             is Song -> {
                 if (unlikelyToBeNull(detailModel.currentAlbum.value).id == item.album.id) {
                     logD("Navigating to a song in this album")
-                    scrollToItem(item.id, adapter)
+                    scrollToItem(item.id)
-                    detailModel.finishNavToItem()
+                    navModel.finishExploreNavigation()
                 } else {
                     logD("Navigating to another album")
                     findNavController()
@@ -149,7 +142,7 @@ class AlbumDetailFragment : DetailFragment(), AlbumDetailAdapter.Listener {
                 if (unlikelyToBeNull(detailModel.currentAlbum.value).id == item.id) {
                     logD("Navigating to the top of this album")
                     binding.detailRecycler.scrollToPosition(0)
-                    detailModel.finishNavToItem()
+                    navModel.finishExploreNavigation()
                 } else {
                     logD("Navigating to another album")
                     findNavController()
@@ -169,9 +162,9 @@ class AlbumDetailFragment : DetailFragment(), AlbumDetailAdapter.Listener {
     }
 
     /** Scroll to an song using its [id]. */
-    private fun scrollToItem(id: Long, adapter: AlbumDetailAdapter) {
+    private fun scrollToItem(id: Long) {
         // Calculate where the item for the currently played song is
-        val pos = adapter.data.currentList.indexOfFirst { it.id == id && it is Song }
+        val pos = detailAdapter.data.currentList.indexOfFirst { it.id == id && it is Song }
 
         if (pos != -1) {
             val binding = requireBinding()
@@ -189,7 +182,7 @@ class AlbumDetailFragment : DetailFragment(), AlbumDetailAdapter.Listener {
     }
 
     /** Updates the queue actions when a song is present or not */
-    private fun updateSong(song: Song?, adapter: AlbumDetailAdapter) {
+    private fun updateSong(song: Song?) {
         val binding = requireBinding()
 
         for (item in binding.detailToolbar.menu.children) {
@@ -200,10 +193,10 @@ class AlbumDetailFragment : DetailFragment(), AlbumDetailAdapter.Listener {
 
         if (playbackModel.playbackMode.value == PlaybackMode.IN_ALBUM &&
             playbackModel.parent.value?.id == unlikelyToBeNull(detailModel.currentAlbum.value).id) {
-            adapter.highlightSong(song, binding.detailRecycler)
+            detailAdapter.highlightSong(song, binding.detailRecycler)
         } else {
             // Clear the ViewHolders if the mode isn't ALL_SONGS
-            adapter.highlightSong(null, binding.detailRecycler)
+            detailAdapter.highlightSong(null, binding.detailRecycler)
         }
     }
 

app/src/main/java/org/oxycblt/auxio/detail/ArtistDetailFragment.kt

@@ -63,27 +63,16 @@ class ArtistDetailFragment : DetailFragment(), DetailAdapter.Listener {
 
         // --- VIEWMODEL SETUP ---
 
-        detailModel.artistData.observe(viewLifecycleOwner) { list ->
+        detailModel.artistData.observe(viewLifecycleOwner, detailAdapter.data::submitList)
-            detailAdapter.data.submitList(list)
+        navModel.exploreNavigationItem.observe(viewLifecycleOwner, ::handleNavigation)
-        }
+        playbackModel.song.observe(viewLifecycleOwner, ::updateSong)
-
+        playbackModel.parent.observe(viewLifecycleOwner, ::updateParent)
-        detailModel.navToItem.observe(viewLifecycleOwner, ::handleNavigation)
-
-        // Highlight songs if they are being played
-        playbackModel.song.observe(viewLifecycleOwner) { song -> updateSong(song, detailAdapter) }
-
-        // Highlight albums if they are being played
-        playbackModel.parent.observe(viewLifecycleOwner) { parent ->
-            updateParent(parent, detailAdapter)
-        }
     }
 
     override fun onItemClick(item: Item) {
         when (item) {
             is Song -> playbackModel.playSong(item, PlaybackMode.IN_ARTIST)
-            is Album ->
+            is Album -> navModel.exploreNavigateTo(item)
-                findNavController()
-                    .navigate(ArtistDetailFragmentDirections.actionShowAlbum(item.id))
         }
     }
 
@@ -111,49 +100,49 @@ class ArtistDetailFragment : DetailFragment(), DetailAdapter.Listener {
         val binding = requireBinding()
 
         when (item) {
-            is Artist -> {
+            is Song -> {
-                if (item.id == detailModel.currentArtist.value?.id) {
+                logD("Navigating to another album")
-                    logD("Navigating to the top of this artist")
-                    binding.detailRecycler.scrollToPosition(0)
-                    detailModel.finishNavToItem()
-                } else {
-                    logD("Navigating to another artist")
                 findNavController()
-                        .navigate(ArtistDetailFragmentDirections.actionShowArtist(item.id))
+                    .navigate(ArtistDetailFragmentDirections.actionShowAlbum(item.album.id))
-                }
             }
             is Album -> {
                 logD("Navigating to another album")
                 findNavController()
                     .navigate(ArtistDetailFragmentDirections.actionShowAlbum(item.id))
             }
-            is Song -> {
+            is Artist -> {
-                logD("Navigating to another album")
+                if (item.id == detailModel.currentArtist.value?.id) {
+                    logD("Navigating to the top of this artist")
+                    binding.detailRecycler.scrollToPosition(0)
+                    navModel.finishExploreNavigation()
+                } else {
+                    logD("Navigating to another artist")
                     findNavController()
-                    .navigate(ArtistDetailFragmentDirections.actionShowAlbum(item.album.id))
+                        .navigate(ArtistDetailFragmentDirections.actionShowArtist(item.id))
+                }
             }
             null -> {}
             else -> logW("Unsupported navigation item ${item::class.java}")
         }
     }
 
-    private fun updateSong(song: Song?, adapter: ArtistDetailAdapter) {
+    private fun updateSong(song: Song?) {
         val binding = requireBinding()
         if (playbackModel.playbackMode.value == PlaybackMode.IN_ARTIST &&
             playbackModel.parent.value?.id == detailModel.currentArtist.value?.id) {
-            adapter.highlightSong(song, binding.detailRecycler)
+            detailAdapter.highlightSong(song, binding.detailRecycler)
         } else {
             // Clear the ViewHolders if the mode isn't ALL_SONGS
-            adapter.highlightSong(null, binding.detailRecycler)
+            detailAdapter.highlightSong(null, binding.detailRecycler)
         }
     }
 
-    private fun updateParent(parent: MusicParent?, adapter: ArtistDetailAdapter) {
+    private fun updateParent(parent: MusicParent?) {
         val binding = requireBinding()
         if (parent is Album?) {
-            adapter.highlightAlbum(parent, binding.detailRecycler)
+            detailAdapter.highlightAlbum(parent, binding.detailRecycler)
         } else {
-            adapter.highlightAlbum(null, binding.detailRecycler)
+            detailAdapter.highlightAlbum(null, binding.detailRecycler)
         }
     }
 }

app/src/main/java/org/oxycblt/auxio/detail/DetailFragment.kt

@@ -29,6 +29,7 @@ import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentDetailBinding
 import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.playback.PlaybackViewModel
+import org.oxycblt.auxio.ui.NavigationViewModel
 import org.oxycblt.auxio.ui.Sort
 import org.oxycblt.auxio.ui.ViewBindingFragment
 import org.oxycblt.auxio.util.logD
@@ -40,16 +41,12 @@ import org.oxycblt.auxio.util.unlikelyToBeNull
  */
 abstract class DetailFragment : ViewBindingFragment<FragmentDetailBinding>() {
     protected val detailModel: DetailViewModel by activityViewModels()
+    protected val navModel: NavigationViewModel by activityViewModels()
     protected val playbackModel: PlaybackViewModel by activityViewModels()
 
     override fun onCreateBinding(inflater: LayoutInflater): FragmentDetailBinding =
         FragmentDetailBinding.inflate(inflater)
 
-    override fun onResume() {
-        super.onResume()
-        detailModel.setNavigating(false)
-    }
-
     override fun onDestroyBinding(binding: FragmentDetailBinding) {
         super.onDestroyBinding(binding)
         binding.detailRecycler.adapter = null

app/src/main/java/org/oxycblt/auxio/detail/DetailViewModel.kt

@@ -25,7 +25,6 @@ import org.oxycblt.auxio.detail.recycler.SortHeader
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.Genre
-import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.settings.SettingsManager
 import org.oxycblt.auxio.ui.Header
@@ -38,7 +37,6 @@ import org.oxycblt.auxio.util.logD
  * - What item the fragment should be showing
  * - The RecyclerView data for each fragment
  * - Menu triggers for each fragment
- * - Navigation triggers for each fragment [e.g "Go to artist"]
  * @author OxygenCobalt
  */
 class DetailViewModel : ViewModel() {
@@ -87,15 +85,6 @@ class DetailViewModel : ViewModel() {
             currentGenre.value?.let(::refreshGenreData)
         }
 
-    private val mNavToItem = MutableLiveData<Music?>()
-
-    /** Flag for unified navigation. Observe this to coordinate navigation to an item's UI. */
-    val navToItem: LiveData<Music?>
-        get() = mNavToItem
-
-    var isNavigating = false
-        private set
-
     fun setAlbumId(id: Long) {
         if (mCurrentAlbum.value?.id == id) return
         val musicStore = MusicStore.requireInstance()
@@ -122,21 +111,6 @@ class DetailViewModel : ViewModel() {
         refreshGenreData(genre)
     }
 
-    /** Navigate to an item, whether a song/album/artist */
-    fun navToItem(item: Music) {
-        mNavToItem.value = item
-    }
-
-    /** Mark that the navigation process is done. */
-    fun finishNavToItem() {
-        mNavToItem.value = null
-    }
-
-    /** Update the current navigation status to [isNavigating] */
-    fun setNavigating(navigating: Boolean) {
-        isNavigating = navigating
-    }
-
     private fun refreshGenreData(genre: Genre) {
         logD("Refreshing genre data")
         val data = mutableListOf<Item>(genre)

app/src/main/java/org/oxycblt/auxio/detail/GenreDetailFragment.kt

@@ -36,7 +36,6 @@ import org.oxycblt.auxio.ui.Item
 import org.oxycblt.auxio.ui.newMenu
 import org.oxycblt.auxio.util.applySpans
 import org.oxycblt.auxio.util.logD
-import org.oxycblt.auxio.util.logW
 import org.oxycblt.auxio.util.unlikelyToBeNull
 
 /**
@@ -61,13 +60,9 @@ class GenreDetailFragment : DetailFragment(), DetailAdapter.Listener {
 
         // --- VIEWMODEL SETUP ---
 
-        detailModel.genreData.observe(viewLifecycleOwner) { list ->
+        detailModel.genreData.observe(viewLifecycleOwner, detailAdapter.data::submitList)
-            detailAdapter.data.submitList(list)
+        navModel.exploreNavigationItem.observe(viewLifecycleOwner, ::handleNavigation)
-        }
+        playbackModel.song.observe(viewLifecycleOwner, ::updateSong)
-
-        detailModel.navToItem.observe(viewLifecycleOwner, ::handleNavigation)
-
-        playbackModel.song.observe(viewLifecycleOwner) { song -> updateSong(song, detailAdapter) }
     }
 
     override fun onItemClick(item: Item) {
@@ -97,34 +92,36 @@ class GenreDetailFragment : DetailFragment(), DetailAdapter.Listener {
 
     private fun handleNavigation(item: Music?) {
         when (item) {
+            is Song -> {
+                logD("Navigating to another song")
+                findNavController()
+                    .navigate(GenreDetailFragmentDirections.actionShowAlbum(item.album.id))
+            }
+            is Album -> {
+                logD("Navigating to another album")
+                findNavController().navigate(GenreDetailFragmentDirections.actionShowAlbum(item.id))
+            }
             // All items will launch new detail fragments.
             is Artist -> {
                 logD("Navigating to another artist")
                 findNavController()
                     .navigate(GenreDetailFragmentDirections.actionShowArtist(item.id))
             }
-            is Album -> {
+            is Genre -> {
-                logD("Navigating to another album")
+                navModel.finishExploreNavigation()
-                findNavController().navigate(GenreDetailFragmentDirections.actionShowAlbum(item.id))
-            }
-            is Song -> {
-                logD("Navigating to another song")
-                findNavController()
-                    .navigate(GenreDetailFragmentDirections.actionShowAlbum(item.album.id))
             }
             null -> {}
-            else -> logW("Unsupported navigation command ${item::class.java}")
         }
     }
 
-    private fun updateSong(song: Song?, adapter: GenreDetailAdapter) {
+    private fun updateSong(song: Song?) {
         val binding = requireBinding()
         if (playbackModel.playbackMode.value == PlaybackMode.IN_GENRE &&
             playbackModel.parent.value?.id == unlikelyToBeNull(detailModel.currentGenre.value).id) {
-            adapter.highlightSong(song, binding.detailRecycler)
+            detailAdapter.highlightSong(song, binding.detailRecycler)
         } else {
             // Clear the ViewHolders if the mode isn't ALL_SONGS
-            adapter.highlightSong(null, binding.detailRecycler)
+            detailAdapter.highlightSong(null, binding.detailRecycler)
         }
     }
 }

app/src/main/java/org/oxycblt/auxio/home/HomeFragment.kt

@@ -28,10 +28,8 @@ import androidx.recyclerview.widget.RecyclerView
 import androidx.viewpager2.adapter.FragmentStateAdapter
 import androidx.viewpager2.widget.ViewPager2
 import com.google.android.material.tabs.TabLayoutMediator
-import org.oxycblt.auxio.MainFragmentDirections
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentHomeBinding
-import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.home.list.AlbumListFragment
 import org.oxycblt.auxio.home.list.ArtistListFragment
 import org.oxycblt.auxio.home.list.GenreListFragment
@@ -45,6 +43,8 @@ import org.oxycblt.auxio.music.MusicViewModel
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.DisplayMode
+import org.oxycblt.auxio.ui.MainNavigationAction
+import org.oxycblt.auxio.ui.NavigationViewModel
 import org.oxycblt.auxio.ui.ViewBindingFragment
 import org.oxycblt.auxio.util.logD
 import org.oxycblt.auxio.util.logE
@@ -62,7 +62,7 @@ import org.oxycblt.auxio.util.unlikelyToBeNull
  */
 class HomeFragment : ViewBindingFragment<FragmentHomeBinding>() {
     private val playbackModel: PlaybackViewModel by activityViewModels()
-    private val detailModel: DetailViewModel by activityViewModels()
+    private val navModel: NavigationViewModel by activityViewModels()
     private val homeModel: HomeViewModel by activityViewModels()
     private val musicModel: MusicViewModel by activityViewModels()
 
@@ -108,7 +108,7 @@ class HomeFragment : ViewBindingFragment<FragmentHomeBinding>() {
         homeModel.recreateTabs.observe(viewLifecycleOwner, ::handleRecreateTabs)
 
         musicModel.loaderResponse.observe(viewLifecycleOwner, ::handleLoaderResponse)
-        detailModel.navToItem.observe(viewLifecycleOwner, ::handleNavigation)
+        navModel.exploreNavigationItem.observe(viewLifecycleOwner, ::handleNavigation)
     }
 
     private fun onMenuClick(item: MenuItem) {
@@ -119,19 +119,15 @@ class HomeFragment : ViewBindingFragment<FragmentHomeBinding>() {
             }
             R.id.action_settings -> {
                 logD("Navigating to settings")
-                parentFragment
+                navModel.mainNavigateTo(MainNavigationAction.SETTINGS)
-                    ?.parentFragment
-                    ?.findNavController()
-                    ?.navigate(MainFragmentDirections.actionShowSettings())
             }
             R.id.action_about -> {
                 logD("Navigating to about")
-                parentFragment
+                navModel.mainNavigateTo(MainNavigationAction.ABOUT)
-                    ?.parentFragment
+            }
-                    ?.findNavController()
+            R.id.submenu_sorting -> {
-                    ?.navigate(MainFragmentDirections.actionShowAbout())
+                // Junk click event when opening the menu
             }
-            R.id.submenu_sorting -> {}
             R.id.option_sort_asc -> {
                 item.isChecked = !item.isChecked
                 homeModel.updateCurrentSort(

app/src/main/java/org/oxycblt/auxio/home/list/AlbumListFragment.kt

@@ -18,11 +18,10 @@
 package org.oxycblt.auxio.home.list
 
 import android.view.View
-import androidx.navigation.fragment.findNavController
 import androidx.recyclerview.widget.RecyclerView
 import org.oxycblt.auxio.R
-import org.oxycblt.auxio.home.HomeFragmentDirections
 import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.ui.AlbumViewHolder
 import org.oxycblt.auxio.ui.DisplayMode
 import org.oxycblt.auxio.ui.Item
@@ -70,8 +69,8 @@ class AlbumListFragment : HomeListFragment<Album>() {
     }
 
     override fun onItemClick(item: Item) {
-        check(item is Album)
+        check(item is Music)
-        findNavController().navigate(HomeFragmentDirections.actionShowAlbum(item.id))
+        navModel.exploreNavigateTo(item)
     }
 
     override fun onOpenMenu(item: Item, anchor: View) {

app/src/main/java/org/oxycblt/auxio/home/list/ArtistListFragment.kt

@@ -18,11 +18,10 @@
 package org.oxycblt.auxio.home.list
 
 import android.view.View
-import androidx.navigation.fragment.findNavController
 import androidx.recyclerview.widget.RecyclerView
 import org.oxycblt.auxio.R
-import org.oxycblt.auxio.home.HomeFragmentDirections
 import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.ui.ArtistViewHolder
 import org.oxycblt.auxio.ui.Item
 import org.oxycblt.auxio.ui.MenuItemListener
@@ -56,8 +55,8 @@ class ArtistListFragment : HomeListFragment<Artist>() {
             .uppercase()
 
     override fun onItemClick(item: Item) {
-        check(item is Artist)
+        check(item is Music)
-        findNavController().navigate(HomeFragmentDirections.actionShowArtist(item.id))
+        navModel.exploreNavigateTo(item)
     }
 
     override fun onOpenMenu(item: Item, anchor: View) {

app/src/main/java/org/oxycblt/auxio/home/list/GenreListFragment.kt

@@ -18,11 +18,10 @@
 package org.oxycblt.auxio.home.list
 
 import android.view.View
-import androidx.navigation.fragment.findNavController
 import androidx.recyclerview.widget.RecyclerView
 import org.oxycblt.auxio.R
-import org.oxycblt.auxio.home.HomeFragmentDirections
 import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.ui.GenreViewHolder
 import org.oxycblt.auxio.ui.Item
 import org.oxycblt.auxio.ui.MenuItemListener
@@ -56,8 +55,8 @@ class GenreListFragment : HomeListFragment<Genre>() {
             .uppercase()
 
     override fun onItemClick(item: Item) {
-        check(item is Genre)
+        check(item is Music)
-        findNavController().navigate(HomeFragmentDirections.actionShowGenre(item.id))
+        navModel.exploreNavigateTo(item)
     }
 
     override fun onOpenMenu(item: Item, anchor: View) {

app/src/main/java/org/oxycblt/auxio/home/list/HomeListFragment.kt

@@ -28,6 +28,7 @@ import org.oxycblt.auxio.home.fastscroll.FastScrollRecyclerView
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.Item
 import org.oxycblt.auxio.ui.MenuItemListener
+import org.oxycblt.auxio.ui.NavigationViewModel
 import org.oxycblt.auxio.ui.ViewBindingFragment
 
 /**
@@ -41,8 +42,9 @@ abstract class HomeListFragment<T : Item> :
     FastScrollRecyclerView.OnFastScrollListener {
     abstract fun setupRecycler(recycler: RecyclerView)
 
-    protected val homeModel: HomeViewModel by activityViewModels()
     protected val playbackModel: PlaybackViewModel by activityViewModels()
+    protected val navModel: NavigationViewModel by activityViewModels()
+    protected val homeModel: HomeViewModel by activityViewModels()
 
     override fun onCreateBinding(inflater: LayoutInflater) =
         FragmentHomeListBinding.inflate(inflater)

app/src/main/java/org/oxycblt/auxio/home/tabs/Tab.kt

@@ -54,7 +54,7 @@ sealed class Tab(open val mode: DisplayMode) {
         const val SEQUENCE_DEFAULT = 0b1000_1001_1010_1011_0100
 
         /**
-         * Maps between the integer code in the tab sequence and the actual [DisplayMode] instance
+         * Maps between the integer code in the tab sequence and the actual [DisplayMode] instance.
          */
         private val MODE_TABLE =
             arrayOf(

app/src/main/java/org/oxycblt/auxio/playback/PlaybackBarFragment.kt

@@ -27,8 +27,8 @@ import com.google.android.material.color.MaterialColors
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.coil.bindAlbumCover
 import org.oxycblt.auxio.databinding.FragmentPlaybackBarBinding
-import org.oxycblt.auxio.detail.DetailViewModel
+import org.oxycblt.auxio.ui.MainNavigationAction
-import org.oxycblt.auxio.ui.BottomSheetLayout
+import org.oxycblt.auxio.ui.NavigationViewModel
 import org.oxycblt.auxio.ui.ViewBindingFragment
 import org.oxycblt.auxio.util.getAttrColorSafe
 import org.oxycblt.auxio.util.systemBarInsetsCompat
@@ -36,7 +36,7 @@ import org.oxycblt.auxio.util.textSafe
 
 class PlaybackBarFragment : ViewBindingFragment<FragmentPlaybackBarBinding>() {
     private val playbackModel: PlaybackViewModel by activityViewModels()
-    private val detailModel: DetailViewModel by activityViewModels()
+    private val navModel: NavigationViewModel by activityViewModels()
 
     override fun onCreateBinding(inflater: LayoutInflater) =
         FragmentPlaybackBarBinding.inflate(inflater)
@@ -46,14 +46,10 @@ class PlaybackBarFragment : ViewBindingFragment<FragmentPlaybackBarBinding>() {
         savedInstanceState: Bundle?
     ) {
         binding.root.apply {
-            setOnClickListener {
+            setOnClickListener { navModel.mainNavigateTo(MainNavigationAction.EXPAND) }
-                // This is a dumb and fragile hack but this fragment isn't part of the navigation
-                // stack so we can't really do much
-                (requireView().parent.parent.parent as BottomSheetLayout).expand()
-            }
 
             setOnLongClickListener {
-                playbackModel.song.value?.let { song -> detailModel.navToItem(song) }
+                playbackModel.song.value?.let(navModel::exploreNavigateTo)
                 true
             }
 

app/src/main/java/org/oxycblt/auxio/playback/PlaybackPanelFragment.kt

@@ -23,11 +23,9 @@ import android.view.MenuItem
 import androidx.core.view.updatePadding
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
-import androidx.navigation.fragment.findNavController
 import com.google.android.material.color.MaterialColors
 import com.google.android.material.slider.Slider
 import kotlin.math.max
-import org.oxycblt.auxio.MainFragmentDirections
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.coil.bindAlbumCover
 import org.oxycblt.auxio.databinding.FragmentPlaybackPanelBinding
@@ -36,7 +34,8 @@ import org.oxycblt.auxio.music.MusicParent
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.toDuration
 import org.oxycblt.auxio.playback.state.LoopMode
-import org.oxycblt.auxio.ui.BottomSheetLayout
+import org.oxycblt.auxio.ui.MainNavigationAction
+import org.oxycblt.auxio.ui.NavigationViewModel
 import org.oxycblt.auxio.ui.ViewBindingFragment
 import org.oxycblt.auxio.util.getAttrColorSafe
 import org.oxycblt.auxio.util.logD
@@ -56,6 +55,7 @@ class PlaybackPanelFragment :
     Slider.OnChangeListener,
     Slider.OnSliderTouchListener {
     private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val navModel: NavigationViewModel by activityViewModels()
     private val detailModel: DetailViewModel by activityViewModels()
 
     override fun onCreateBinding(inflater: LayoutInflater) =
@@ -75,11 +75,11 @@ class PlaybackPanelFragment :
         val queueItem: MenuItem
 
         binding.playbackToolbar.apply {
-            setNavigationOnClickListener { navigateUp() }
+            setNavigationOnClickListener { navModel.mainNavigateTo(MainNavigationAction.COLLAPSE) }
 
             setOnMenuItemClickListener { item ->
                 if (item.itemId == R.id.action_queue) {
-                    findNavController().navigate(MainFragmentDirections.actionShowQueue())
+                    navModel.mainNavigateTo(MainNavigationAction.QUEUE)
                     true
                 } else {
                     false
@@ -92,15 +92,15 @@ class PlaybackPanelFragment :
         binding.playbackSong.apply {
             // Make marquee of the song title work
             isSelected = true
-            setOnClickListener { playbackModel.song.value?.let { detailModel.navToItem(it) } }
+            setOnClickListener { playbackModel.song.value?.let(navModel::exploreNavigateTo) }
         }
 
         binding.playbackArtist.setOnClickListener {
-            playbackModel.song.value?.let { detailModel.navToItem(it.album.artist) }
+            playbackModel.song.value?.let { navModel.exploreNavigateTo(it.album.artist) }
         }
 
         binding.playbackAlbum.setOnClickListener {
-            playbackModel.song.value?.let { detailModel.navToItem(it.album) }
+            playbackModel.song.value?.let { navModel.exploreNavigateTo(it.album) }
         }
 
         binding.playbackSeekBar.apply {
@@ -141,12 +141,6 @@ class PlaybackPanelFragment :
             queueItem.isEnabled = nextUp.isNotEmpty()
         }
 
-        detailModel.navToItem.observe(viewLifecycleOwner) { item ->
-            if (item != null) {
-                navigateUp()
-            }
-        }
-
         logD("Fragment Created")
     }
 
@@ -218,10 +212,4 @@ class PlaybackPanelFragment :
     private fun updateShuffle(isShuffling: Boolean) {
         requireBinding().playbackShuffle.isActivated = isShuffling
     }
-
-    private fun navigateUp() {
-        // This is a dumb and fragile hack but this fragment isn't part of the navigation stack
-        // so we can't really do much
-        (requireView().parent.parent.parent as BottomSheetLayout).collapse()
-    }
 }

app/src/main/java/org/oxycblt/auxio/search/SearchFragment.kt

@@ -30,7 +30,6 @@ import androidx.fragment.app.viewModels
 import androidx.navigation.fragment.findNavController
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentSearchBinding
-import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.Genre
@@ -41,11 +40,11 @@ import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.Header
 import org.oxycblt.auxio.ui.Item
 import org.oxycblt.auxio.ui.MenuItemListener
+import org.oxycblt.auxio.ui.NavigationViewModel
 import org.oxycblt.auxio.ui.ViewBindingFragment
 import org.oxycblt.auxio.ui.newMenu
 import org.oxycblt.auxio.util.applySpans
 import org.oxycblt.auxio.util.getSystemServiceSafe
-import org.oxycblt.auxio.util.logD
 import org.oxycblt.auxio.util.requireAttached
 
 /**
@@ -56,7 +55,7 @@ class SearchFragment : ViewBindingFragment<FragmentSearchBinding>(), MenuItemLis
     // SearchViewModel is only scoped to this Fragment
     private val searchModel: SearchViewModel by viewModels()
     private val playbackModel: PlaybackViewModel by activityViewModels()
-    private val detailModel: DetailViewModel by activityViewModels()
+    private val navModel: NavigationViewModel by activityViewModels()
 
     private val searchAdapter = SearchAdapter(this)
     private var imm: InputMethodManager? = null
@@ -109,11 +108,7 @@ class SearchFragment : ViewBindingFragment<FragmentSearchBinding>(), MenuItemLis
         // --- VIEWMODEL SETUP ---
 
         searchModel.searchResults.observe(viewLifecycleOwner, ::updateResults)
-
+        navModel.exploreNavigationItem.observe(viewLifecycleOwner, ::handleNavigation)
-        detailModel.navToItem.observe(viewLifecycleOwner) { item ->
-            handleNavigation(item)
-            requireImm().hide()
-        }
     }
 
     override fun onResume() {
@@ -128,25 +123,9 @@ class SearchFragment : ViewBindingFragment<FragmentSearchBinding>(), MenuItemLis
     }
 
     override fun onItemClick(item: Item) {
-        if (item is Song) {
-            playbackModel.playSong(item)
-            return
-        }
-
-        if (item is MusicParent && !searchModel.isNavigating) {
-            searchModel.setNavigating(true)
-
-            logD("Navigating to the detail fragment for ${item.rawName}")
-
-            findNavController()
-                .navigate(
         when (item) {
-                        is Genre -> SearchFragmentDirections.actionShowGenre(item.id)
+            is Song -> playbackModel.playSong(item)
-                        is Artist -> SearchFragmentDirections.actionShowArtist(item.id)
+            is MusicParent -> navModel.exploreNavigateTo(item)
-                        is Album -> SearchFragmentDirections.actionShowAlbum(item.id)
-                    })
-
-            requireImm().hide()
         }
     }
 
@@ -178,8 +157,11 @@ class SearchFragment : ViewBindingFragment<FragmentSearchBinding>(), MenuItemLis
                     is Song -> SearchFragmentDirections.actionShowAlbum(item.album.id)
                     is Album -> SearchFragmentDirections.actionShowAlbum(item.id)
                     is Artist -> SearchFragmentDirections.actionShowArtist(item.id)
+                    is Genre -> SearchFragmentDirections.actionShowGenre(item.id)
                     else -> return
                 })
+
+        requireImm().hide()
     }
 
     private fun requireImm(): InputMethodManager {

app/src/main/java/org/oxycblt/auxio/search/SearchViewModel.kt

@@ -47,8 +47,6 @@ class SearchViewModel : ViewModel() {
     /** Current search results from the last [search] call. */
     val searchResults: LiveData<List<Item>>
         get() = mSearchResults
-    val isNavigating: Boolean
-        get() = mIsNavigating
     val filterMode: DisplayMode?
         get() = mFilterMode
 

app/src/main/java/org/oxycblt/auxio/ui/ActionMenu.kt

@@ -26,7 +26,6 @@ import androidx.core.view.children
 import androidx.fragment.app.Fragment
 import androidx.lifecycle.ViewModelProvider
 import org.oxycblt.auxio.R
-import org.oxycblt.auxio.detail.DetailViewModel
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.Genre
@@ -70,8 +69,8 @@ class ActionMenu(
     private val context = activity.applicationContext
 
     // Get ViewModels using the activity as the store owner
-    private val detailModel: DetailViewModel by lazy {
+    private val navModel: NavigationViewModel by lazy {
-        ViewModelProvider(activity)[DetailViewModel::class.java]
+        ViewModelProvider(activity)[NavigationViewModel::class.java]
     }
 
     private val playbackModel: PlaybackViewModel by lazy {
@@ -172,14 +171,14 @@ class ActionMenu(
             }
             R.id.action_go_album -> {
                 if (data is Song) {
-                    detailModel.navToItem(data.album)
+                    navModel.exploreNavigateTo(data.album)
                 }
             }
             R.id.action_go_artist -> {
                 if (data is Song) {
-                    detailModel.navToItem(data.album.artist)
+                    navModel.exploreNavigateTo(data.album.artist)
                 } else if (data is Album) {
-                    detailModel.navToItem(data.artist)
+                    navModel.exploreNavigateTo(data.artist)
                 }
             }
         }

app/src/main/java/org/oxycblt/auxio/ui/NavigationViewModel.kt

@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2022 Auxio Project
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.ui
+
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.ViewModel
+import org.oxycblt.auxio.music.Music
+
+/**
+ * A ViewModel that handles complicated navigation situations.
+ */
+class NavigationViewModel : ViewModel() {
+    private val mMainNavigationAction = MutableLiveData<MainNavigationAction?>()
+    /** Flag for main fragment navigation. Intended for MainFragment use only. */
+    val mainNavigationAction: LiveData<MainNavigationAction?>
+        get() = mMainNavigationAction
+
+    private val mExploreNavigationItem = MutableLiveData<Music?>()
+    /** Flag for unified navigation. Observe this to coordinate navigation to an item's UI. */
+    val exploreNavigationItem: LiveData<Music?>
+        get() = mExploreNavigationItem
+
+    /**
+     * Notify MainFragment to navigate to the location outlined in [MainNavigationAction].
+     */
+    fun mainNavigateTo(action: MainNavigationAction) {
+        if (mMainNavigationAction.value != null) return
+        mMainNavigationAction.value = action
+    }
+
+    /** Mark that the main navigation process is done. */
+    fun finishMainNavigation() {
+        mMainNavigationAction.value = null
+    }
+
+    /** Navigate to an item's detail menu, whether a song/album/artist */
+    fun exploreNavigateTo(item: Music) {
+        if (mExploreNavigationItem.value != null) return
+        mExploreNavigationItem.value = item
+    }
+
+    /** Mark that the item navigation process is done. */
+    fun finishExploreNavigation() {
+        mExploreNavigationItem.value = null
+    }
+}
+
+/**
+ * Represents the navigation options for the Main Fragment, which tends to be multiple layers above
+ * normal fragments. This can be passed to [NavigationViewModel.mainNavigateTo] in order to
+ * facilitate navigation without stupid fragment hacks.
+ */
+enum class MainNavigationAction {
+    /** Expand the playback panel. */
+    EXPAND,
+    /** Collapse the playback panel. */
+    COLLAPSE,
+    /** Go to settings. */
+    SETTINGS,
+    /** Go to the about page. */
+    ABOUT,
+    /** Go to the queue. */
+    QUEUE
+}

app/src/main/res/layout-land/fragment_playback_panel.xml

@@ -94,6 +94,7 @@
         app:thumbRadius="@dimen/slider_thumb_radius" />
 
     <TextView
+        android:id="@+id/playback_position"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginStart="@dimen/spacing_medium"
@@ -105,6 +106,7 @@
         tools:text="11:38" />
 
     <TextView
+        android:id="@+id/playback_duration"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="@dimen/spacing_small_inv"

app/src/main/res/layout-sw600dp-land/fragment_playback_panel.xml

@@ -92,6 +92,7 @@
         app:thumbRadius="@dimen/slider_thumb_radius" />
 
     <TextView
+        android:id="@+id/playback_position"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginStart="@dimen/spacing_medium"
@@ -103,6 +104,7 @@
         tools:text="11:38" />
 
     <TextView
+        android:id="@+id/playback_duration"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="@dimen/spacing_small_inv"

app/src/main/res/layout-sw600dp/fragment_playback_panel.xml

@@ -81,6 +81,7 @@
         app:thumbRadius="@dimen/slider_thumb_radius" />
 
     <TextView
+        android:id="@+id/playback_position"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginStart="@dimen/spacing_medium"
@@ -92,6 +93,7 @@
         tools:text="11:38" />
 
     <TextView
+        android:id="@+id/playback_duration"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="@dimen/spacing_small_inv"

app/src/main/res/layout-w600dp-land/fragment_playback_panel.xml

@@ -94,6 +94,7 @@
         app:thumbRadius="@dimen/slider_thumb_radius" />
 
     <TextView
+        android:id="@+id/playback_position"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginStart="@dimen/spacing_medium"
@@ -105,6 +106,7 @@
         tools:text="11:38" />
 
     <TextView
+        android:id="@+id/playback_duration"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="@dimen/spacing_small_inv"

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

@@ -2,6 +2,7 @@
 <androidx.recyclerview.widget.RecyclerView 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/accent_recycler"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:overScrollMode="never"

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

@@ -7,8 +7,8 @@
     android:orientation="vertical"
     android:paddingTop="@dimen/spacing_small">
 
-
     <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/excluded_recycler"
         android:layout_width="match_parent"
         android:layout_height="0dp"
         android:layout_gravity="center"
@@ -19,6 +19,7 @@
         tools:listitem="@layout/item_excluded_dir" />
 
     <TextView
+        android:id="@+id/excluded_empty"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:padding="@dimen/spacing_medium"

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

@@ -2,6 +2,7 @@
 <androidx.recyclerview.widget.RecyclerView 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/tab_recycler"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:overScrollMode="never"

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

@@ -8,16 +8,19 @@
     tools:context=".settings.AboutFragment">
 
     <org.oxycblt.auxio.ui.EdgeAppBarLayout
+        android:id="@+id/about_appbar"
         style="@style/Widget.Auxio.AppBarLayout"
         app:liftOnScroll="true">
 
         <com.google.android.material.appbar.MaterialToolbar
+            android:id="@+id/about_toolbar"
             style="@style/Widget.Auxio.Toolbar.Icon"
             app:title="@string/lbl_about" />
 
     </org.oxycblt.auxio.ui.EdgeAppBarLayout>
 
     <androidx.core.widget.NestedScrollView
+        android:id="@+id/about_contents"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:clipToPadding="false"

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

@@ -10,6 +10,7 @@
         android:layout_height="match_parent">
 
         <org.oxycblt.auxio.detail.DetailAppBarLayout
+            android:id="@+id/detail_appbar"
             style="@style/Widget.Auxio.AppBarLayout"
             app:liftOnScroll="true"
             app:liftOnScrollTargetViewId="@id/detail_recycler">

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

@@ -6,15 +6,18 @@
     android:layout_height="match_parent">
 
     <org.oxycblt.auxio.ui.EdgeAppBarLayout
+        android:id="@+id/home_appbar"
         style="@style/Widget.Auxio.AppBarLayout"
         app:liftOnScroll="true">
 
         <com.google.android.material.appbar.MaterialToolbar
+            android:id="@+id/home_toolbar"
             style="@style/Widget.Auxio.Toolbar"
             app:menu="@menu/menu_home"
             app:title="@string/info_app_name" />
 
         <com.google.android.material.tabs.TabLayout
+            android:id="@+id/home_tabs"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:background="@android:color/transparent"
@@ -40,6 +43,7 @@
         app:layout_anchorGravity="bottom|end">
 
         <com.google.android.material.floatingactionbutton.FloatingActionButton
+            android:id="@+id/home_fab"
             style="@style/Widget.Auxio.FloatingActionButton.Adaptive"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"

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

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
-
 <org.oxycblt.auxio.home.fastscroll.FastScrollRecyclerView 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"
     style="@style/Widget.Auxio.RecyclerView.WithAdaptiveFab"
+    android:id="@+id/home_recycler"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"

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

@@ -6,6 +6,7 @@
     android:layout_height="match_parent">
 
     <org.oxycblt.auxio.ui.BottomSheetLayout
+        android:id="@+id/bottom_sheet_layout"
         android:layout_width="match_parent"
         android:layout_height="match_parent">
 
@@ -32,6 +33,7 @@
     </org.oxycblt.auxio.ui.BottomSheetLayout>
 
     <FrameLayout
+        android:id="@+id/layout_too_small"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:background="?attr/colorSurface"

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

@@ -78,6 +78,7 @@
         app:thumbRadius="@dimen/slider_thumb_radius" />
 
     <TextView
+        android:id="@+id/playback_position"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginStart="@dimen/spacing_medium"
@@ -89,6 +90,7 @@
         tools:text="11:38" />
 
     <TextView
+        android:id="@+id/playback_duration"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="@dimen/spacing_small_inv"

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

@@ -12,6 +12,7 @@
         app:liftOnScrollTargetViewId="@id/queue_recycler">
 
         <com.google.android.material.appbar.MaterialToolbar
+            android:id="@+id/queue_toolbar"
             style="@style/Widget.Auxio.Toolbar.Icon.Down"
             android:elevation="0dp"
             app:navigationIcon="@drawable/ic_down"

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

@@ -11,6 +11,7 @@
         app:liftOnScrollTargetViewId="@id/search_recycler">
 
         <com.google.android.material.appbar.MaterialToolbar
+            android:id="@+id/search_toolbar"
             style="@style/Widget.Auxio.Toolbar.Icon"
             app:menu="@menu/menu_search">
 
@@ -25,6 +26,7 @@
                 app:hintEnabled="false">
 
                 <com.google.android.material.textfield.TextInputEditText
+                    android:id="@+id/search_edit_text"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
                     android:background="@android:color/transparent"

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

@@ -7,12 +7,14 @@
     android:orientation="vertical">
 
     <org.oxycblt.auxio.ui.EdgeAppBarLayout
+        android:id="@+id/settings_appbar"
         style="@style/Widget.Auxio.AppBarLayout"
         android:clickable="true"
         android:focusable="true"
         app:liftOnScroll="true">
 
         <com.google.android.material.appbar.MaterialToolbar
+            android:id="@+id/settings_toolbar"
             style="@style/Widget.Auxio.Toolbar.Icon"
             app:title="@string/set_title" />
 

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

@@ -8,6 +8,7 @@
     android:theme="@style/ThemeOverlay.Accent">
 
     <ImageButton
+        android:id="@+id/accent"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_gravity="center"

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

@@ -11,6 +11,7 @@
     view. The way we do this is odd, but it's designed this way-->
 
     <org.oxycblt.auxio.coil.StyledImageView
+        android:id="@+id/song_track_bg"
         style="@style/Widget.Auxio.Image.Small"
         android:src="@drawable/ic_song"
         android:scaleType="matrix"

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

@@ -11,6 +11,7 @@
     android:padding="0dp">
 
     <TextView
+        android:id="@+id/excluded_path"
         style="@style/Widget.Auxio.TextView.Item.Primary"
         android:layout_width="0dp"
         android:layout_height="wrap_content"

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

@@ -6,6 +6,7 @@
     android:layout_height="wrap_content">
 
     <View
+        android:id="@+id/background"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:background="?attr/colorPrimary"
@@ -21,6 +22,7 @@
         app:tint="?attr/colorSurface" />
 
     <androidx.constraintlayout.widget.ConstraintLayout
+        android:id="@+id/body"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:background="?attr/colorSurface">

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

@@ -7,6 +7,7 @@
     android:layout_height="wrap_content">
 
     <TextView
+        android:id="@+id/header_title"
         style="@style/Widget.Auxio.TextView.Header"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
@@ -16,6 +17,7 @@
         tools:text="Songs" />
 
     <ImageButton
+        android:id="@+id/header_button"
         style="@style/Widget.AppCompat.Button.Borderless"
         android:layout_width="0dp"
         android:layout_height="wrap_content"