Refactor library structure

Refactor LibraryFragment & LibraryViewModel so that LibraryViewModel only holds the data and LibraryFragment displays it.

app/src/main/java/org/oxycblt/auxio/library/LibraryFragment.kt

@@ -23,7 +23,6 @@ import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.BaseModel
 import org.oxycblt.auxio.music.Genre
-import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.playback.state.PlaybackMode
@@ -51,10 +50,7 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
     ): View {
         val binding = FragmentLibraryBinding.inflate(inflater)
 
-        val musicStore = MusicStore.getInstance()
-
         val libraryAdapter = LibraryAdapter(
-            libraryModel.displayMode.value!!,
             doOnClick = { navToItem(it) },
             doOnLongClick = { data, view -> showActionsForItem(data, view) }
         )
@@ -127,16 +123,21 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
 
         // --- VIEWMODEL SETUP ---
 
+        libraryModel.libraryData.observe(viewLifecycleOwner) {
+            libraryAdapter.updateData(it)
+        }
+
+        libraryModel.searchResults.observe(viewLifecycleOwner) {
+            if (libraryModel.searchHasFocus) {
+                searchAdapter.submitList(it) {
+                    binding.libraryRecycler.scrollToPosition(0)
+                }
+            }
+        }
+
         libraryModel.sortMode.observe(viewLifecycleOwner) { mode ->
             Log.d(this::class.simpleName, "Updating sort mode to $mode")
 
-            // Update the adapter with the new data
-            libraryAdapter.updateData(
-                mode.getSortedBaseModelList(
-                    musicStore.getListForShowMode(libraryModel.displayMode.value!!)
-                )
-            )
-
             // Then update the menu item in the toolbar to reflect the new mode
             binding.libraryToolbar.menu.forEach {
                 if (it.itemId == libraryModel.sortMode.value!!.toMenuId()) {
@@ -147,14 +148,6 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
             }
         }
 
-        libraryModel.searchResults.observe(viewLifecycleOwner) {
-            if (libraryModel.searchHasFocus) {
-                searchAdapter.submitList(it) {
-                    binding.libraryRecycler.scrollToPosition(0)
-                }
-            }
-        }
-
         playbackModel.navToItem.observe(viewLifecycleOwner) {
             if (it != null) {
                 libraryModel.updateNavigationStatus(false)
@@ -188,6 +181,7 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
 
     private fun showActionsForItem(data: BaseModel, view: View) {
         val menu = PopupMenu(requireContext(), view)
+
         when (data) {
             is Song -> menu.setupSongActions(data, requireContext(), playbackModel)
             is Album -> menu.setupAlbumActions(data, requireContext(), playbackModel)

app/src/main/java/org/oxycblt/auxio/library/LibraryViewModel.kt

@@ -21,15 +21,17 @@ import org.oxycblt.auxio.settings.SettingsManager
  * @author OxygenCobalt
  */
 class LibraryViewModel : ViewModel(), SettingsManager.Callback {
-    private val mDisplayMode = MutableLiveData(DisplayMode.SHOW_ARTISTS)
-    val displayMode: LiveData<DisplayMode> get() = mDisplayMode
-
     private val mSortMode = MutableLiveData(SortMode.ALPHA_DOWN)
     val sortMode: LiveData<SortMode> get() = mSortMode
 
+    private val mLibraryData = MutableLiveData(listOf<BaseModel>())
+    val libraryData: LiveData<List<BaseModel>> get() = mLibraryData
+
     private val mSearchResults = MutableLiveData(listOf<BaseModel>())
     val searchResults: LiveData<List<BaseModel>> get() = mSearchResults
 
+    private var mDisplayMode = DisplayMode.SHOW_ARTISTS
+
     private var mIsNavigating = false
     val isNavigating: Boolean get() = mIsNavigating
 
@@ -37,14 +39,19 @@ class LibraryViewModel : ViewModel(), SettingsManager.Callback {
     val searchHasFocus: Boolean get() = mSearchHasFocus
 
     private val settingsManager = SettingsManager.getInstance()
+    private val musicStore = MusicStore.getInstance()
 
     init {
         settingsManager.addCallback(this)
 
-        mDisplayMode.value = settingsManager.libraryDisplayMode
+        mDisplayMode = settingsManager.libraryDisplayMode
         mSortMode.value = settingsManager.librarySortMode
+
+        updateLibraryData()
     }
 
+    // --- SEARCH FUNCTIONS ---
+
     /**
      * Perform a search of the music library, given a query.
      * Results are pushed to [searchResults].
@@ -63,9 +70,8 @@ class LibraryViewModel : ViewModel(), SettingsManager.Callback {
         // the query, and update the LiveData with those items. This is done on a separate
         // thread as it can be a very long operation for large music libraries.
         viewModelScope.launch {
-            val musicStore = MusicStore.getInstance()
             val combined = mutableListOf<BaseModel>()
-            val children = displayMode.value!!.getChildren()
+            val children = mDisplayMode.getChildren()
 
             // If the Library DisplayMode supports it, include artists / genres in the search.
             if (children.contains(DisplayMode.SHOW_GENRES)) {
@@ -105,17 +111,15 @@ class LibraryViewModel : ViewModel(), SettingsManager.Callback {
         }
     }
 
+    fun updateSearchFocusStatus(value: Boolean) {
+        mSearchHasFocus = value
+    }
+
     fun resetQuery() {
         mSearchResults.value = listOf()
     }
 
-    fun updateNavigationStatus(value: Boolean) {
+    // --- LIBRARY FUNCTIONS ---
-        mIsNavigating = value
-    }
-
-    fun updateSearchFocusStatus(value: Boolean) {
-        mSearchHasFocus = value
-    }
 
     fun updateSortMode(@IdRes itemId: Int) {
         val mode = when (itemId) {
@@ -128,11 +132,16 @@ class LibraryViewModel : ViewModel(), SettingsManager.Callback {
 
         if (mode != mSortMode.value) {
             mSortMode.value = mode
-
             settingsManager.librarySortMode = mode
+
+            updateLibraryData()
         }
     }
 
+    fun updateNavigationStatus(value: Boolean) {
+        mIsNavigating = value
+    }
+
     // --- OVERRIDES ---
 
     override fun onCleared() {
@@ -142,6 +151,16 @@ class LibraryViewModel : ViewModel(), SettingsManager.Callback {
     }
 
     override fun onLibDisplayModeUpdate(displayMode: DisplayMode) {
-        mDisplayMode.value = displayMode
+        mDisplayMode = displayMode
+
+        updateLibraryData()
+    }
+
+    // --- UTILS ---
+
+    private fun updateLibraryData() {
+        mLibraryData.value = mSortMode.value!!.getSortedBaseModelList(
+            musicStore.getListForShowMode(mDisplayMode)
+        )
     }
 }

app/src/main/java/org/oxycblt/auxio/library/adapters/LibraryAdapter.kt

@@ -1,69 +1,77 @@
 package org.oxycblt.auxio.library.adapters
 
+import android.util.Log
 import android.view.View
 import android.view.ViewGroup
+import androidx.recyclerview.widget.AsyncListDiffer
+import androidx.recyclerview.widget.ListAdapter
 import androidx.recyclerview.widget.RecyclerView
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.BaseModel
 import org.oxycblt.auxio.music.Genre
-import org.oxycblt.auxio.recycler.DisplayMode
+import org.oxycblt.auxio.music.Header
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.recycler.DiffCallback
 import org.oxycblt.auxio.recycler.viewholders.AlbumViewHolder
 import org.oxycblt.auxio.recycler.viewholders.ArtistViewHolder
 import org.oxycblt.auxio.recycler.viewholders.GenreViewHolder
+import org.oxycblt.auxio.recycler.viewholders.HeaderViewHolder
+import org.oxycblt.auxio.recycler.viewholders.SongViewHolder
 
 /**
- * The primary recyclerview for the library. Can display either Genres, Artists, and Albums.
+ * A near-identical adapter as [SearchAdapter] but this one isn't a [ListAdapter]
+ * Id love to unify these two adapters but that triggers a bug on the android backend, so...
  * @author OxygenCobalt
  */
 class LibraryAdapter(
-    private val displayMode: DisplayMode,
     private val doOnClick: (data: BaseModel) -> Unit,
     private val doOnLongClick: (data: BaseModel, view: View) -> Unit
 ) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
 
-    private var data: List<BaseModel>
+    private var data = listOf<BaseModel>()
-
-    init {
-        // Assign the data on startup depending on the type
-        data = when (displayMode) {
-            DisplayMode.SHOW_GENRES -> listOf<Genre>()
-            DisplayMode.SHOW_ARTISTS -> listOf<Artist>()
-            DisplayMode.SHOW_ALBUMS -> listOf<Album>()
-
-            else -> listOf<Artist>()
-        }
-    }
 
     override fun getItemCount(): Int = data.size
 
-    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
+    override fun getItemViewType(position: Int): Int {
-        // Return a different View Holder depending on the show type
+        return when (data[position]) {
-        return when (displayMode) {
+            is Genre -> GenreViewHolder.ITEM_TYPE
-            DisplayMode.SHOW_GENRES -> GenreViewHolder.from(parent.context, doOnClick, doOnLongClick)
+            is Artist -> ArtistViewHolder.ITEM_TYPE
-            DisplayMode.SHOW_ARTISTS -> ArtistViewHolder.from(parent.context, doOnClick, doOnLongClick)
+            is Album -> AlbumViewHolder.ITEM_TYPE
-            DisplayMode.SHOW_ALBUMS -> AlbumViewHolder.from(parent.context, doOnClick, doOnLongClick)
 
-            else -> error("Bad DisplayMode given.")
+            else -> -1
+        }
+    }
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
+        return when (viewType) {
+            GenreViewHolder.ITEM_TYPE -> GenreViewHolder.from(
+                parent.context, doOnClick, doOnLongClick
+            )
+
+            ArtistViewHolder.ITEM_TYPE -> ArtistViewHolder.from(
+                parent.context, doOnClick, doOnLongClick
+            )
+
+            AlbumViewHolder.ITEM_TYPE -> AlbumViewHolder.from(
+                parent.context, doOnClick, doOnLongClick
+            )
+
+            else -> error("Invalid viewholder item type.")
         }
     }
 
     override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
-        when (displayMode) {
+        when (val item = data[position]) {
-            DisplayMode.SHOW_GENRES -> (holder as GenreViewHolder).bind(data[position] as Genre)
+            is Genre -> (holder as GenreViewHolder).bind(item)
-            DisplayMode.SHOW_ARTISTS -> (holder as ArtistViewHolder).bind(data[position] as Artist)
+            is Artist -> (holder as ArtistViewHolder).bind(item)
-            DisplayMode.SHOW_ALBUMS -> (holder as AlbumViewHolder).bind(data[position] as Album)
+            is Album -> (holder as AlbumViewHolder).bind(item)
-
-            else -> return
         }
     }
 
-    // Update the data, as its an internal value.
     fun updateData(newData: List<BaseModel>) {
-        if (data != newData) {
+        data = newData
-            data = newData
 
-            notifyDataSetChanged()
+        notifyDataSetChanged()
-        }
     }
 }

app/src/main/java/org/oxycblt/auxio/library/adapters/SearchAdapter.kt

@@ -1,7 +1,9 @@
 package org.oxycblt.auxio.library.adapters
 
+import android.util.Log
 import android.view.View
 import android.view.ViewGroup
+import androidx.recyclerview.widget.AsyncListDiffer
 import androidx.recyclerview.widget.ListAdapter
 import androidx.recyclerview.widget.RecyclerView
 import org.oxycblt.auxio.music.Album

app/src/main/java/org/oxycblt/auxio/recycler/NoLeakThumbView.kt

@@ -29,9 +29,10 @@ import org.oxycblt.auxio.ui.toColor
 
 /**
  * A semi-copy, semi-custom implementation of [com.reddit.indicatorfastscroll.FastScrollerThumbView]
- * that fixes a memory leak that occurs from a bug fix they added. All credit goes to the authors of
+ * that fixes a memory leak that occurs from a bug fix they added.
- * the fast scroll library.
+ * All credit goes to the authors of the fast scroll library.
- * <a href="https://github.com/reddit/IndicatorFastScroll"> Link to repo </a>
+ *
+ * https://github.com/reddit/IndicatorFastScroll
  * @author Reddit, OxygenCobalt
  */
 class NoLeakThumbView @JvmOverloads constructor(

app/src/main/java/org/oxycblt/auxio/songs/SongsFragment.kt

@@ -68,6 +68,13 @@ class SongsFragment : Fragment() {
         binding.songRecycler.apply {
             adapter = songAdapter
             setHasFixedSize(true)
+
+            post {
+                if (computeVerticalScrollRange() < height) {
+                    binding.songFastScroll.visibility = View.GONE
+                    binding.songFastScrollThumb.visibility = View.GONE
+                }
+            }
         }
 
         setupFastScroller(binding)

app/src/main/res/values/styles.xml

@@ -80,6 +80,7 @@
         <item name="colorPrimary">@color/control_color</item>
         <item name="colorSecondary">@color/control_color</item>
         <item name="dialogCornerRadius">0dp</item>
+        <item name="colorControlHighlight">@color/selection_color</item>
     </style>
 
     <!-- Custom dialog title theme -->