Change music storage to shared object

Change MusicViewModel from a ViewModel to a shared object, so that it can be used everywhere in the app instead of just in fragments.

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

@@ -14,7 +14,8 @@ import com.google.android.material.tabs.TabLayout
 import com.google.android.material.tabs.TabLayoutMediator
 import org.oxycblt.auxio.databinding.FragmentMainBinding
 import org.oxycblt.auxio.library.LibraryFragment
-import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.loading.LoadingViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.songs.SongsFragment
 import org.oxycblt.auxio.theme.accent
 import org.oxycblt.auxio.theme.getInactiveAlpha
@@ -22,8 +23,8 @@ import org.oxycblt.auxio.theme.getTransparentAccent
 import org.oxycblt.auxio.theme.toColor
 
 class MainFragment : Fragment() {
-    private val musicModel: MusicViewModel by activityViewModels {
+    private val loadingModel: LoadingViewModel by activityViewModels {
-        MusicViewModel.Factory(requireActivity().application)
+        LoadingViewModel.Factory(requireActivity().application)
     }
 
     private val shownFragments = listOf(0, 1)
@@ -39,9 +40,9 @@ class MainFragment : Fragment() {
     ): View? {
         val binding = FragmentMainBinding.inflate(inflater)
 
-        // If musicModel was cleared while the app was closed [Likely due to Auxio being suspended
+        // If the music was cleared while the app was closed [Likely due to Auxio being suspended
         // in the background], then navigate back to LoadingFragment to reload the music.
-        if (musicModel.response.value == null) {
+        if (MusicStore.getInstance().songs.isEmpty()) {
             findNavController().navigate(MainFragmentDirections.actionReturnToLoading())
 
             return null

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

@@ -12,7 +12,7 @@ import androidx.navigation.fragment.navArgs
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentAlbumDetailBinding
 import org.oxycblt.auxio.detail.adapters.DetailSongAdapter
-import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.theme.applyDivider
 import org.oxycblt.auxio.theme.disable
@@ -22,7 +22,6 @@ class AlbumDetailFragment : Fragment() {
     private val args: AlbumDetailFragmentArgs by navArgs()
     private val detailModel: DetailViewModel by activityViewModels()
     private val playbackModel: PlaybackViewModel by activityViewModels()
-    private val musicModel: MusicViewModel by activityViewModels()
 
     override fun onCreateView(
         inflater: LayoutInflater,
@@ -31,22 +30,21 @@ class AlbumDetailFragment : Fragment() {
     ): View? {
         val binding = FragmentAlbumDetailBinding.inflate(inflater)
 
-        // If DetailViewModel isn't already storing the album, get it from MusicViewModel
+        // If DetailViewModel isn't already storing the album, get it from MusicStore
         // using the ID given by the navigation arguments.
         if (detailModel.currentAlbum.value == null ||
             detailModel.currentAlbum.value?.id != args.albumId
         ) {
-            val musicModel: MusicViewModel by activityViewModels()
 
             detailModel.updateAlbum(
-                musicModel.albums.value!!.find {
+                MusicStore.getInstance().albums.find {
                     it.id == args.albumId
                 }!!
             )
         }
 
         val songAdapter = DetailSongAdapter {
-            playbackModel.update(it, musicModel.songs.value!!)
+            playbackModel.update(it)
         }
 
         // --- UI SETUP ---

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

@@ -11,7 +11,7 @@ import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
 import org.oxycblt.auxio.databinding.FragmentArtistDetailBinding
 import org.oxycblt.auxio.detail.adapters.DetailAlbumAdapter
-import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.theme.applyDivider
 import org.oxycblt.auxio.theme.disable
 
@@ -30,15 +30,13 @@ class ArtistDetailFragment : Fragment() {
     ): View? {
         val binding = FragmentArtistDetailBinding.inflate(inflater)
 
-        // If DetailViewModel isn't already storing the artist, get it from MusicViewModel
+        // If DetailViewModel isn't already storing the artist, get it from MusicStore
         // using the ID given by the navigation arguments
         if (detailModel.currentArtist.value == null ||
             detailModel.currentArtist.value?.id != args.artistId
         ) {
-            val musicModel: MusicViewModel by activityViewModels()
-
             detailModel.updateArtist(
-                musicModel.artists.value!!.find {
+                MusicStore.getInstance().artists.find {
                     it.id == args.artistId
                 }!!
             )

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

@@ -11,7 +11,7 @@ import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
 import org.oxycblt.auxio.databinding.FragmentGenreDetailBinding
 import org.oxycblt.auxio.detail.adapters.DetailArtistAdapter
-import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.theme.applyDivider
 import org.oxycblt.auxio.theme.disable
 
@@ -27,15 +27,13 @@ class GenreDetailFragment : Fragment() {
     ): View? {
         val binding = FragmentGenreDetailBinding.inflate(inflater)
 
-        // If DetailViewModel isn't already storing the genre, get it from MusicViewModel
+        // If DetailViewModel isn't already storing the genre, get it from MusicStore
         // using the ID given by the navigation arguments
         if (detailModel.currentGenre.value == null ||
             detailModel.currentGenre.value?.id != args.genreId
         ) {
-            val musicModel: MusicViewModel by activityViewModels()
-
             detailModel.updateGenre(
-                musicModel.genres.value!!.find {
+                MusicStore.getInstance().genres.find {
                     it.id == args.genreId
                 }!!
             )

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

@@ -23,10 +23,9 @@ 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.MusicViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
-import org.oxycblt.auxio.recycler.ShowMode
 import org.oxycblt.auxio.theme.applyColor
 import org.oxycblt.auxio.theme.applyDivider
 import org.oxycblt.auxio.theme.resolveAttr
@@ -34,10 +33,6 @@ import org.oxycblt.auxio.theme.resolveAttr
 // A Fragment to show all the music in the Library.
 class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
 
-    private val musicModel: MusicViewModel by activityViewModels {
-        MusicViewModel.Factory(requireActivity().application)
-    }
-
     private val libraryModel: LibraryViewModel by activityViewModels()
     private val playbackModel: PlaybackViewModel by activityViewModels()
 
@@ -48,6 +43,8 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
     ): View? {
         val binding = FragmentLibraryBinding.inflate(inflater)
 
+        val musicStore = MusicStore.getInstance()
+
         val libraryAdapter = LibraryAdapter(libraryModel.showMode.value!!) {
             navToItem(it)
         }
@@ -137,13 +134,7 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
             // Update the adapter with the new data
             libraryAdapter.updateData(
                 mode.getSortedBaseModelList(
-                    when (libraryModel.showMode.value) {
+                    musicStore.getListForShowMode(libraryModel.showMode.value!!)
-                        ShowMode.SHOW_GENRES -> musicModel.genres.value!!
-                        ShowMode.SHOW_ARTISTS -> musicModel.artists.value!!
-                        ShowMode.SHOW_ALBUMS -> musicModel.albums.value!!
-
-                        else -> musicModel.artists.value!!
-                    }
                 )
             )
 
@@ -179,7 +170,7 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
     override fun onQueryTextSubmit(query: String): Boolean = false
 
     override fun onQueryTextChange(query: String): Boolean {
-        libraryModel.updateSearchQuery(query, musicModel)
+        libraryModel.updateSearchQuery(query)
 
         return false
     }
@@ -190,7 +181,7 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
         // If the item is a song [That was selected through search], then update the playback
         // to that song instead of doing any navigation
         if (baseModel is Song) {
-            playbackModel.update(baseModel, musicModel.songs.value!!)
+            playbackModel.update(baseModel)
             return
         }
 

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

@@ -9,7 +9,7 @@ import kotlinx.coroutines.launch
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.music.BaseModel
 import org.oxycblt.auxio.music.Header
-import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.recycler.ShowMode
 import org.oxycblt.auxio.recycler.SortMode
 
@@ -44,7 +44,7 @@ class LibraryViewModel : ViewModel() {
         }
     }
 
-    fun updateSearchQuery(query: String, musicModel: MusicViewModel) {
+    fun updateSearchQuery(query: String) {
         // Don't bother if the query is blank.
         if (query == "") {
             resetQuery()
@@ -52,16 +52,17 @@ class LibraryViewModel : ViewModel() {
             return
         }
 
-        // Search MusicViewModel for all the items [Artists, Albums, Songs] that contain
+        // Search MusicStore for all the items [Artists, Albums, Songs] that contain
         // 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 = showMode.value!!.getChildren()
 
             // If the Library ShowMode supports it, include artists / genres in the search.
             if (children.contains(ShowMode.SHOW_GENRES)) {
-                val genres = musicModel.genres.value!!.filter { it.name.contains(query, true) }
+                val genres = musicStore.genres.filter { it.name.contains(query, true) }
 
                 if (genres.isNotEmpty()) {
                     combined.add(Header(id = ShowMode.SHOW_GENRES.constant))
@@ -70,7 +71,7 @@ class LibraryViewModel : ViewModel() {
             }
 
             if (children.contains(ShowMode.SHOW_ARTISTS)) {
-                val artists = musicModel.artists.value!!.filter { it.name.contains(query, true) }
+                val artists = musicStore.artists.filter { it.name.contains(query, true) }
 
                 if (artists.isNotEmpty()) {
                     combined.add(Header(id = ShowMode.SHOW_ARTISTS.constant))
@@ -79,14 +80,14 @@ class LibraryViewModel : ViewModel() {
             }
 
             // Albums & Songs are always included.
-            val albums = musicModel.albums.value!!.filter { it.name.contains(query, true) }
+            val albums = musicStore.albums.filter { it.name.contains(query, true) }
 
             if (albums.isNotEmpty()) {
                 combined.add(Header(id = ShowMode.SHOW_ALBUMS.constant))
                 combined.addAll(albums)
             }
 
-            val songs = musicModel.songs.value!!.filter { it.name.contains(query, true) }
+            val songs = musicStore.songs.filter { it.name.contains(query, true) }
 
             if (songs.isNotEmpty()) {
                 combined.add(Header(id = ShowMode.SHOW_SONGS.constant))

app/src/main/java/org/oxycblt/auxio/loading/LoadingFragment.kt

@@ -14,13 +14,12 @@ import androidx.fragment.app.activityViewModels
 import androidx.navigation.fragment.findNavController
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentLoadingBinding
-import org.oxycblt.auxio.music.MusicViewModel
 import org.oxycblt.auxio.music.processing.MusicLoaderResponse
 
 class LoadingFragment : Fragment(R.layout.fragment_loading) {
 
-    private val musicModel: MusicViewModel by activityViewModels {
+    private val loadingModel: LoadingViewModel by activityViewModels {
-        MusicViewModel.Factory(requireActivity().application)
+        LoadingViewModel.Factory(requireActivity().application)
     }
 
     override fun onCreateView(
@@ -39,18 +38,18 @@ class LoadingFragment : Fragment(R.layout.fragment_loading) {
                 if (granted) {
                     returnToLoading(binding)
 
-                    musicModel.reload()
+                    loadingModel.reload()
                 }
             }
 
         // --- UI SETUP ---
 
         binding.lifecycleOwner = this
-        binding.musicModel = musicModel
+        binding.loadingModel = loadingModel
 
         // --- VIEWMODEL SETUP ---
 
-        musicModel.response.observe(viewLifecycleOwner) {
+        loadingModel.response.observe(viewLifecycleOwner) {
             if (it == MusicLoaderResponse.DONE) {
                 findNavController().navigate(
                     LoadingFragmentDirections.actionToMain()
@@ -69,17 +68,17 @@ class LoadingFragment : Fragment(R.layout.fragment_loading) {
             }
         }
 
-        musicModel.doReload.observe(viewLifecycleOwner) {
+        loadingModel.doReload.observe(viewLifecycleOwner) {
             if (it) {
                 returnToLoading(binding)
-                musicModel.doneWithReload()
+                loadingModel.doneWithReload()
             }
         }
 
-        musicModel.doGrant.observe(viewLifecycleOwner) {
+        loadingModel.doGrant.observe(viewLifecycleOwner) {
             if (it) {
                 permLauncher.launch(Manifest.permission.READ_EXTERNAL_STORAGE)
-                musicModel.doneWithGrant()
+                loadingModel.doneWithGrant()
             }
         }
 
@@ -90,7 +89,7 @@ class LoadingFragment : Fragment(R.layout.fragment_loading) {
             binding.loadingGrantButton.visibility = View.VISIBLE
             binding.loadingErrorText.text = getString(R.string.error_no_perms)
         } else {
-            musicModel.go()
+            loadingModel.go()
         }
 
         Log.d(this::class.simpleName, "Fragment created.")
@@ -109,7 +108,7 @@ class LoadingFragment : Fragment(R.layout.fragment_loading) {
         ) == PackageManager.PERMISSION_DENIED
     }
 
-    // Remove the loading ui_indicator and show the error groups
+    // Remove the loading indicator and show the error groups
     private fun showError(binding: FragmentLoadingBinding) {
         binding.loadingBar.visibility = View.GONE
         binding.loadingErrorIcon.visibility = View.VISIBLE

app/src/main/java/org/oxycblt/auxio/loading/LoadingViewModel.kt

@@ -0,0 +1,95 @@
+package org.oxycblt.auxio.loading
+
+import android.app.Application
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import org.oxycblt.auxio.music.MusicStore
+import org.oxycblt.auxio.music.processing.MusicLoaderResponse
+
+class LoadingViewModel(private val app: Application) : ViewModel() {
+    // Coroutine
+    private val loadingJob = Job()
+    private val ioScope = CoroutineScope(
+        loadingJob + Dispatchers.IO
+    )
+
+    // UI control
+    private val mResponse = MutableLiveData<MusicLoaderResponse>()
+    val response: LiveData<MusicLoaderResponse> get() = mResponse
+
+    private val mRedo = MutableLiveData<Boolean>()
+    val doReload: LiveData<Boolean> get() = mRedo
+
+    private val mDoGrant = MutableLiveData<Boolean>()
+    val doGrant: LiveData<Boolean> get() = mDoGrant
+
+    private var started = false
+
+    // Start the music loading sequence.
+    // This should only be ran once, use reload() for all other loads.
+    fun go() {
+        if (!started) {
+            started = true
+            doLoad()
+        }
+    }
+
+    private fun doLoad() {
+        ioScope.launch {
+            val musicStore = MusicStore.getInstance()
+
+            val response = musicStore.load(app)
+
+            withContext(Dispatchers.Main) {
+                mResponse.value = response
+            }
+        }
+    }
+
+    // UI communication functions
+    // LoadingFragment uses these so that button presses can update the ViewModel.
+    // all doneWithX functions are to reset the value so that LoadingFragment doesn't
+    // repeat commands if the view is recreated.
+    fun reload() {
+        mRedo.value = true
+
+        doLoad()
+    }
+
+    fun doneWithReload() {
+        mRedo.value = false
+    }
+
+    fun grant() {
+        mDoGrant.value = true
+    }
+
+    fun doneWithGrant() {
+        mDoGrant.value = false
+    }
+
+    override fun onCleared() {
+        super.onCleared()
+
+        // Cancel the current loading job if the app has been stopped
+        loadingJob.cancel()
+    }
+
+    class Factory(private val application: Application) : ViewModelProvider.Factory {
+        @Suppress("unchecked_cast")
+        override fun <T : ViewModel?> create(modelClass: Class<T>): T {
+            if (modelClass.isAssignableFrom(LoadingViewModel::class.java)) {
+                return LoadingViewModel(application) as T
+            }
+
+            throw IllegalArgumentException("Unknown ViewModel class.")
+        }
+    }
+}

app/src/main/java/org/oxycblt/auxio/music/MusicStore.kt

@@ -0,0 +1,100 @@
+package org.oxycblt.auxio.music
+
+import android.app.Application
+import android.util.Log
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.music.processing.MusicLoader
+import org.oxycblt.auxio.music.processing.MusicLoaderResponse
+import org.oxycblt.auxio.music.processing.MusicSorter
+import org.oxycblt.auxio.recycler.ShowMode
+
+// Storage for Music Data. Only use getInstance() to access this object.
+class MusicStore private constructor() {
+    private var mGenres = listOf<Genre>()
+    val genres: List<Genre> get() = mGenres
+
+    private var mArtists = listOf<Artist>()
+    val artists: List<Artist> get() = mArtists
+
+    private var mAlbums = listOf<Album>()
+    val albums: List<Album> get() = mAlbums
+
+    private var mSongs = listOf<Song>()
+    val songs: List<Song> get() = mSongs
+
+    suspend fun load(app: Application): MusicLoaderResponse {
+        Log.i(this::class.simpleName, "Starting initial music load...")
+
+        val start = System.currentTimeMillis()
+
+        // Get the placeholder strings, which are used by MusicLoader & MusicSorter for
+        // any music that doesn't have metadata.
+        val genrePlaceholder = app.getString(R.string.placeholder_genre)
+        val artistPlaceholder = app.getString(R.string.placeholder_artist)
+        val albumPlaceholder = app.getString(R.string.placeholder_album)
+
+        val loader = MusicLoader(
+            app.contentResolver,
+
+            genrePlaceholder,
+            artistPlaceholder,
+            albumPlaceholder
+        )
+
+        if (loader.response == MusicLoaderResponse.DONE) {
+            // If the loading succeeds, then sort the songs and update the value
+            val sorter = MusicSorter(
+                loader.genres,
+                loader.artists,
+                loader.albums,
+                loader.songs,
+
+                genrePlaceholder,
+                artistPlaceholder,
+                albumPlaceholder
+            )
+
+            mSongs = sorter.songs.toList()
+            mAlbums = sorter.albums.toList()
+            mArtists = sorter.artists.toList()
+            mGenres = sorter.genres.toList()
+
+            val elapsed = System.currentTimeMillis() - start
+
+            Log.i(
+                this::class.simpleName,
+                "Music load completed successfully in ${elapsed}ms."
+            )
+        }
+
+        return loader.response
+    }
+
+    fun getListForShowMode(showMode: ShowMode): List<BaseModel> {
+        return when (showMode) {
+            ShowMode.SHOW_GENRES -> mGenres
+            ShowMode.SHOW_ARTISTS -> mArtists
+            ShowMode.SHOW_ALBUMS -> mAlbums
+            ShowMode.SHOW_SONGS -> mSongs
+        }
+    }
+
+    companion object {
+        @Volatile
+        private var INSTANCE: MusicStore? = null
+
+        fun getInstance(): MusicStore {
+            val currentInstance = INSTANCE
+
+            if (currentInstance != null) {
+                return currentInstance
+            }
+
+            synchronized(this) {
+                val newInstance = MusicStore()
+                INSTANCE = newInstance
+                return newInstance
+            }
+        }
+    }
+}

app/src/main/java/org/oxycblt/auxio/music/MusicViewModel.kt

@@ -1,154 +0,0 @@
-package org.oxycblt.auxio.music
-
-import android.app.Application
-import android.util.Log
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.MutableLiveData
-import androidx.lifecycle.ViewModel
-import androidx.lifecycle.ViewModelProvider
-import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.Job
-import kotlinx.coroutines.launch
-import kotlinx.coroutines.withContext
-import org.oxycblt.auxio.R
-import org.oxycblt.auxio.music.processing.MusicLoader
-import org.oxycblt.auxio.music.processing.MusicLoaderResponse
-import org.oxycblt.auxio.music.processing.MusicSorter
-
-// ViewModel for music storage.
-// TODO: Move genre usage to songs [If there's a way to find songs without a genre]
-class MusicViewModel(private val app: Application) : ViewModel() {
-
-    // Coroutine
-    private val loadingJob = Job()
-    private val ioScope = CoroutineScope(
-        loadingJob + Dispatchers.IO
-    )
-
-    // Values
-    private val mGenres = MutableLiveData<List<Genre>>()
-    val genres: LiveData<List<Genre>> get() = mGenres
-
-    private val mArtists = MutableLiveData<List<Artist>>()
-    val artists: LiveData<List<Artist>> get() = mArtists
-
-    private val mAlbums = MutableLiveData<List<Album>>()
-    val albums: LiveData<List<Album>> get() = mAlbums
-
-    private val mSongs = MutableLiveData<List<Song>>()
-    val songs: LiveData<List<Song>> get() = mSongs
-
-    private val mResponse = MutableLiveData<MusicLoaderResponse>()
-    val response: LiveData<MusicLoaderResponse> get() = mResponse
-
-    // UI control
-    private val mRedo = MutableLiveData<Boolean>()
-    val doReload: LiveData<Boolean> get() = mRedo
-
-    private val mDoGrant = MutableLiveData<Boolean>()
-    val doGrant: LiveData<Boolean> get() = mDoGrant
-
-    private var started = false
-
-    // Start the music loading sequence.
-    // This should only be ran once, use reload() for all other loads.
-    fun go() {
-        if (!started) {
-            started = true
-            doLoad()
-        }
-    }
-
-    private fun doLoad() {
-        Log.i(this::class.simpleName, "Starting initial music load...")
-
-        ioScope.launch {
-            val start = System.currentTimeMillis()
-
-            // Get the placeholder strings, which are used by MusicLoader & MusicSorter for
-            // any music that doesn't have metadata.
-            val genrePlaceholder = app.getString(R.string.placeholder_genre)
-            val artistPlaceholder = app.getString(R.string.placeholder_artist)
-            val albumPlaceholder = app.getString(R.string.placeholder_album)
-
-            val loader = MusicLoader(
-                app.contentResolver,
-
-                genrePlaceholder,
-                artistPlaceholder,
-                albumPlaceholder
-            )
-
-            withContext(Dispatchers.Main) {
-                if (loader.response == MusicLoaderResponse.DONE) {
-                    // If the loading succeeds, then sort the songs and update the value
-                    val sorter = MusicSorter(
-                        loader.genres,
-                        loader.artists,
-                        loader.albums,
-                        loader.songs,
-
-                        genrePlaceholder,
-                        artistPlaceholder,
-                        albumPlaceholder
-                    )
-
-                    mSongs.value = sorter.songs.toList()
-                    mAlbums.value = sorter.albums.toList()
-                    mArtists.value = sorter.artists.toList()
-                    mGenres.value = sorter.genres.toList()
-                }
-
-                mResponse.value = loader.response
-
-                val elapsed = System.currentTimeMillis() - start
-
-                Log.i(
-                    this::class.simpleName,
-                    "Music load completed successfully in ${elapsed}ms."
-                )
-            }
-        }
-    }
-
-    // UI communication functions
-    // LoadingFragment uses these so that button presses can update the ViewModel.
-    // all doneWithX functions are to reset the value so that LoadingFragment doesn't
-    // repeat commands if the view is recreated.
-    fun reload() {
-        mRedo.value = true
-
-        doLoad()
-    }
-
-    fun doneWithReload() {
-        mRedo.value = false
-    }
-
-    fun grant() {
-        mDoGrant.value = true
-    }
-
-    fun doneWithGrant() {
-        mDoGrant.value = false
-    }
-
-    override fun onCleared() {
-        super.onCleared()
-
-        // Cancel the current loading job if the app has been stopped
-        loadingJob.cancel()
-    }
-
-    class Factory(private val application: Application) : ViewModelProvider.Factory {
-        @Suppress("unchecked_cast")
-        override fun <T : ViewModel?> create(modelClass: Class<T>): T {
-            if (modelClass.isAssignableFrom(MusicViewModel::class.java)) {
-                return MusicViewModel(application) as T
-            }
-
-            throw IllegalArgumentException("Unknown ViewModel class.")
-        }
-    }
-}

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

@@ -13,14 +13,9 @@ import androidx.navigation.fragment.findNavController
 import org.oxycblt.auxio.MainFragmentDirections
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentCompactPlaybackBinding
-import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.MusicStore
-import kotlin.time.seconds
 
 class CompactPlaybackFragment : Fragment() {
-    private val musicModel: MusicViewModel by activityViewModels {
-        MusicViewModel.Factory(requireActivity().application)
-    }
-
     private val playbackModel: PlaybackViewModel by activityViewModels()
 
     override fun onCreateView(
@@ -44,7 +39,7 @@ class CompactPlaybackFragment : Fragment() {
 
         // Put a placeholder song in the binding & hide the playback fragment initially,
         // as for some reason the attach event doesn't register anymore w/LiveData
-        binding.song = musicModel.songs.value!![0]
+        binding.song = MusicStore.getInstance().songs[0]
         binding.playbackModel = playbackModel
         binding.root.visibility = View.GONE
 

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

@@ -78,12 +78,9 @@ class PlaybackFragment : Fragment(), SeekBar.OnSeekBarChangeListener {
                 binding.playbackSkipPrev.disable(requireContext())
             }
 
-            Log.d(this::class.simpleName, it.toString())
-
             if (it < playbackModel.queue.value!!.lastIndex) {
                 binding.playbackSkipNext.enable(requireContext())
             } else {
-                Log.d(this::class.simpleName, "Fucking stupid retard.")
                 binding.playbackSkipNext.disable(requireContext())
             }
         }

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

@@ -4,6 +4,7 @@ import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.Transformations
 import androidx.lifecycle.ViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.toDuration
 
@@ -40,11 +41,13 @@ class PlaybackViewModel : ViewModel() {
     }
 
     // Update the current song while changing the queue to All Songs.
-    fun update(song: Song, allSongs: List<Song>) {
+    fun update(song: Song) {
+        val musicStore = MusicStore.getInstance()
+
         updatePlayback(song)
 
-        mQueue.value = allSongs.toMutableList()
+        mQueue.value = musicStore.songs.toMutableList()
-        mCurrentIndex.value = allSongs.indexOf(song)
+        mCurrentIndex.value = musicStore.songs.indexOf(song)
     }
 
     private fun updatePlayback(song: Song) {

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

@@ -8,15 +8,11 @@ import android.view.ViewGroup
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
 import org.oxycblt.auxio.databinding.FragmentSongsBinding
-import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.theme.applyDivider
 
 class SongsFragment : Fragment() {
-    private val musicModel: MusicViewModel by activityViewModels {
-        MusicViewModel.Factory(requireActivity().application)
-    }
-
     private val playbackModel: PlaybackViewModel by activityViewModels()
 
     override fun onCreateView(
@@ -26,14 +22,16 @@ class SongsFragment : Fragment() {
     ): View? {
         val binding = FragmentSongsBinding.inflate(inflater)
 
+        val musicStore = MusicStore.getInstance()
+
         // TODO: Add option to search songs if LibraryFragment isn't enabled
         // TODO: Maybe add fast scrolling or sorting
 
         // --- UI SETUP ---
 
         binding.songRecycler.apply {
-            adapter = SongAdapter(musicModel.songs.value!!) {
+            adapter = SongAdapter(musicStore.songs) {
-                playbackModel.update(it, musicModel.songs.value!!)
+                playbackModel.update(it)
             }
             applyDivider()
             setHasFixedSize(true)

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

@@ -7,8 +7,8 @@
     <data>
 
         <variable
-            name="musicModel"
+            name="loadingModel"
-            type="org.oxycblt.auxio.music.MusicViewModel" />
+            type="org.oxycblt.auxio.loading.LoadingViewModel" />
     </data>
 
     <androidx.constraintlayout.widget.ConstraintLayout
@@ -66,7 +66,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:fontFamily="@font/inter_semibold"
-            android:onClick="@{() -> musicModel.reload()}"
+            android:onClick="@{() -> loadingModel.reload()}"
             android:text="@string/label_retry"
             android:textColor="?attr/colorPrimary"
             android:visibility="gone"
@@ -85,7 +85,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:fontFamily="@font/inter_semibold"
-            android:onClick="@{() -> musicModel.grant()}"
+            android:onClick="@{() -> loadingModel.grant()}"
             android:text="@string/label_grant"
             android:textColor="?attr/colorPrimary"
             android:visibility="gone"