home: refactor list management

Return to the "four seperate list fragments" system when it comes to
HomeFragment. This reduces code complexity [no more massive when
chains] and allows me to customize the content of each fragment without
adding special cases.

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

@@ -36,6 +36,10 @@ 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
+import org.oxycblt.auxio.home.list.SongListFragment
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.Genre
@@ -242,6 +246,14 @@ class HomeFragment : Fragment() {
         FragmentStateAdapter(childFragmentManager, viewLifecycleOwner.lifecycle) {
 
         override fun getItemCount(): Int = homeModel.tabs.value!!.size
-        override fun createFragment(position: Int): Fragment = HomeListFragment.new(position)
+
+        override fun createFragment(position: Int): Fragment {
+            return when (homeModel.tabs.value!![position]) {
+                DisplayMode.SHOW_SONGS -> SongListFragment()
+                DisplayMode.SHOW_ALBUMS -> AlbumListFragment()
+                DisplayMode.SHOW_ARTISTS -> ArtistListFragment()
+                DisplayMode.SHOW_GENRES -> GenreListFragment()
+            }
+        }
     }
 }

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

@@ -1,151 +0,0 @@
-/*
- * Copyright (c) 2021 Auxio Project
- * HomeListFragment.kt is part of Auxio.
- *
- * 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.home
-
-import android.os.Bundle
-import android.view.LayoutInflater
-import android.view.View
-import android.view.ViewGroup
-import androidx.annotation.IdRes
-import androidx.fragment.app.Fragment
-import androidx.fragment.app.activityViewModels
-import androidx.lifecycle.LiveData
-import androidx.navigation.fragment.findNavController
-import org.oxycblt.auxio.BuildConfig
-import org.oxycblt.auxio.R
-import org.oxycblt.auxio.databinding.FragmentHomeListBinding
-import org.oxycblt.auxio.home.recycler.HomeAdapter
-import org.oxycblt.auxio.home.recycler.ParentAdapter
-import org.oxycblt.auxio.home.recycler.SongsAdapter
-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.Parent
-import org.oxycblt.auxio.music.Song
-import org.oxycblt.auxio.playback.PlaybackViewModel
-import org.oxycblt.auxio.ui.DisplayMode
-import org.oxycblt.auxio.ui.newMenu
-import org.oxycblt.auxio.util.applySpans
-import org.oxycblt.auxio.util.logD
-
-/**
- * Fragment that contains a list of items specified by a [DisplayMode]. This fragment
- * should be created using the [new] method with it's position in the ViewPager.
- */
-class HomeListFragment : Fragment() {
-    private val homeModel: HomeViewModel by activityViewModels()
-    private val playbackModel: PlaybackViewModel by activityViewModels()
-
-    override fun onCreateView(
-        inflater: LayoutInflater,
-        container: ViewGroup?,
-        savedInstanceState: Bundle?
-    ): View {
-        val binding = FragmentHomeListBinding.inflate(inflater)
-
-        // Get some tab-specific values before we go ahead. More specifically, the data to use
-        // and the unique ID that HomeFragment's AppBarLayout uses to determine lift state.
-        val pos = requireNotNull(arguments).getInt(ARG_POS)
-
-        @IdRes val customId: Int
-        val homeAdapter: HomeAdapter<out BaseModel>
-        val homeData: LiveData<out List<BaseModel>>
-
-        when (homeModel.tabs.value!![pos]) {
-            DisplayMode.SHOW_SONGS -> {
-                customId = R.id.home_song_list
-                homeData = homeModel.songs
-                homeAdapter = SongsAdapter(::onSongClick, ::newMenu, playbackModel)
-            }
-            DisplayMode.SHOW_ALBUMS -> {
-                customId = R.id.home_album_list
-                homeData = homeModel.albums
-                homeAdapter = ParentAdapter(::onParentClick, ::newMenu)
-            }
-            DisplayMode.SHOW_ARTISTS -> {
-                customId = R.id.home_artist_list
-                homeData = homeModel.artists
-                homeAdapter = ParentAdapter(::onParentClick, ::newMenu)
-            }
-            DisplayMode.SHOW_GENRES -> {
-                customId = R.id.home_genre_list
-                homeData = homeModel.genres
-                homeAdapter = ParentAdapter(::onParentClick, ::newMenu)
-            }
-        }
-
-        // --- UI SETUP ---
-
-        binding.lifecycleOwner = viewLifecycleOwner
-
-        binding.homeRecycler.apply {
-            id = customId
-            adapter = homeAdapter
-            setHasFixedSize(true)
-            applySpans()
-        }
-
-        // --- VIEWMODEL SETUP ---
-
-        // Make sure that this RecyclerView has data before startup
-        homeData.observe(viewLifecycleOwner) { data ->
-            homeAdapter.updateData(data)
-        }
-
-        logD("Fragment created")
-
-        return binding.root
-    }
-
-    private fun onSongClick(song: Song) {
-        playbackModel.playSong(song)
-    }
-
-    private fun onParentClick(parent: Parent) {
-        when (parent) {
-            is Album -> findNavController().navigate(
-                HomeFragmentDirections.actionShowAlbum(parent.id)
-            )
-
-            is Artist -> findNavController().navigate(
-                HomeFragmentDirections.actionShowArtist(parent.id)
-            )
-
-            is Genre -> findNavController().navigate(
-                HomeFragmentDirections.actionShowGenre(parent.id)
-            )
-        }
-    }
-
-    companion object {
-        private const val ARG_POS = BuildConfig.APPLICATION_ID + ".key.POS"
-
-        /*
-         * Instantiates this fragment for use in a ViewPager.
-         */
-        fun new(pos: Int): HomeListFragment {
-            val fragment = HomeListFragment()
-            fragment.arguments = Bundle().apply {
-                putInt(ARG_POS, pos)
-            }
-            return fragment
-        }
-    }
-}

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

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2021 Auxio Project
+ * AlbumListFragment.kt is part of Auxio.
+ *
+ * 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.home.list
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.navigation.fragment.findNavController
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.home.HomeFragmentDirections
+import org.oxycblt.auxio.music.Album
+import org.oxycblt.auxio.ui.AlbumViewHolder
+import org.oxycblt.auxio.ui.newMenu
+
+class AlbumListFragment : HomeListFragment() {
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View {
+        binding.lifecycleOwner = viewLifecycleOwner
+
+        val adapter = AlbumAdapter(
+            doOnClick = { album ->
+                findNavController().navigate(
+                    HomeFragmentDirections.actionShowAlbum(album.id)
+                )
+            },
+            ::newMenu
+        )
+
+        setupRecycler(R.id.home_album_list, adapter, homeModel.albums)
+
+        return binding.root
+    }
+
+    class AlbumAdapter(
+        private val doOnClick: (data: Album) -> Unit,
+        private val doOnLongClick: (view: View, data: Album) -> Unit,
+    ) : HomeAdapter<Album, AlbumViewHolder>() {
+        override fun getItemCount(): Int = data.size
+
+        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): AlbumViewHolder {
+            return AlbumViewHolder.from(parent.context, doOnClick, doOnLongClick)
+        }
+
+        override fun onBindViewHolder(holder: AlbumViewHolder, position: Int) {
+            holder.bind(data[position])
+        }
+    }
+}

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

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2021 Auxio Project
+ * AlbumListFragment.kt is part of Auxio.
+ *
+ * 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.home.list
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.navigation.fragment.findNavController
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.home.HomeFragmentDirections
+import org.oxycblt.auxio.music.Artist
+import org.oxycblt.auxio.ui.ArtistViewHolder
+import org.oxycblt.auxio.ui.newMenu
+
+class ArtistListFragment : HomeListFragment() {
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View {
+        binding.lifecycleOwner = viewLifecycleOwner
+
+        val adapter = ArtistAdapter(
+            doOnClick = { artist ->
+                findNavController().navigate(
+                    HomeFragmentDirections.actionShowArtist(artist.id)
+                )
+            },
+            ::newMenu
+        )
+
+        setupRecycler(R.id.home_artist_list, adapter, homeModel.artists)
+
+        return binding.root
+    }
+
+    class ArtistAdapter(
+        private val doOnClick: (data: Artist) -> Unit,
+        private val doOnLongClick: (view: View, data: Artist) -> Unit,
+    ) : HomeAdapter<Artist, ArtistViewHolder>() {
+        override fun getItemCount(): Int = data.size
+
+        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ArtistViewHolder {
+            return ArtistViewHolder.from(parent.context, doOnClick, doOnLongClick)
+        }
+
+        override fun onBindViewHolder(holder: ArtistViewHolder, position: Int) {
+            holder.bind(data[position])
+        }
+    }
+}

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

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2021 Auxio Project
+ * AlbumListFragment.kt is part of Auxio.
+ *
+ * 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.home.list
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.navigation.fragment.findNavController
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.home.HomeFragmentDirections
+import org.oxycblt.auxio.music.Genre
+import org.oxycblt.auxio.ui.GenreViewHolder
+import org.oxycblt.auxio.ui.newMenu
+
+class GenreListFragment : HomeListFragment() {
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View {
+        binding.lifecycleOwner = viewLifecycleOwner
+
+        val adapter = GenreAdapter(
+            doOnClick = { Genre ->
+                findNavController().navigate(
+                    HomeFragmentDirections.actionShowGenre(Genre.id)
+                )
+            },
+            ::newMenu
+        )
+
+        setupRecycler(R.id.home_genre_list, adapter, homeModel.genres)
+
+        return binding.root
+    }
+
+    class GenreAdapter(
+        private val doOnClick: (data: Genre) -> Unit,
+        private val doOnLongClick: (view: View, data: Genre) -> Unit,
+    ) : HomeAdapter<Genre, GenreViewHolder>() {
+        override fun getItemCount(): Int = data.size
+
+        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): GenreViewHolder {
+            return GenreViewHolder.from(parent.context, doOnClick, doOnLongClick)
+        }
+
+        override fun onBindViewHolder(holder: GenreViewHolder, position: Int) {
+            holder.bind(data[position])
+        }
+    }
+}

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

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2021 Auxio Project
+ * HomeListFragment.kt is part of Auxio.
+ *
+ * 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.home.list
+
+import android.annotation.SuppressLint
+import androidx.annotation.IdRes
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
+import androidx.lifecycle.LiveData
+import androidx.recyclerview.widget.RecyclerView
+import org.oxycblt.auxio.databinding.FragmentHomeListBinding
+import org.oxycblt.auxio.home.HomeViewModel
+import org.oxycblt.auxio.music.BaseModel
+import org.oxycblt.auxio.playback.PlaybackViewModel
+import org.oxycblt.auxio.ui.memberBinding
+import org.oxycblt.auxio.util.applySpans
+
+open class HomeListFragment : Fragment() {
+    protected val binding: FragmentHomeListBinding by memberBinding(
+        FragmentHomeListBinding::inflate
+    )
+
+    protected val homeModel: HomeViewModel by activityViewModels()
+    protected val playbackModel: PlaybackViewModel by activityViewModels()
+
+    protected fun <T : BaseModel, VH : RecyclerView.ViewHolder> setupRecycler(
+        @IdRes uniqueId: Int,
+        homeAdapter: HomeAdapter<T, VH>,
+        homeData: LiveData<List<T>>,
+    ) {
+        binding.homeRecycler.apply {
+            id = uniqueId
+            adapter = homeAdapter
+            setHasFixedSize(true)
+            applySpans()
+        }
+
+        // Make sure that this RecyclerView has data before startup
+        homeData.observe(viewLifecycleOwner) { data ->
+            homeAdapter.updateData(data)
+        }
+    }
+
+    abstract class HomeAdapter<T : BaseModel, VH : RecyclerView.ViewHolder> : RecyclerView.Adapter<VH>() {
+        protected var data = listOf<T>()
+
+        @SuppressLint("NotifyDataSetChanged")
+        fun updateData(newData: List<T>) {
+            data = newData
+            notifyDataSetChanged()
+        }
+    }
+}

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

@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2021 Auxio Project
+ * SongListFragment.kt is part of Auxio.
+ *
+ * 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.home.list
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.recyclerview.widget.RecyclerView
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.databinding.ItemPlayShuffleBinding
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.ui.SongViewHolder
+import org.oxycblt.auxio.ui.newMenu
+import org.oxycblt.auxio.util.inflater
+
+class SongListFragment : HomeListFragment() {
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View {
+        binding.lifecycleOwner = viewLifecycleOwner
+
+        val adapter = SongsAdapter(
+            doOnClick = { song ->
+                playbackModel.playSong(song)
+            },
+            ::newMenu
+        )
+
+        setupRecycler(R.id.home_song_list, adapter, homeModel.songs)
+
+        return binding.root
+    }
+
+    inner class SongsAdapter(
+        private val doOnClick: (data: Song) -> Unit,
+        private val doOnLongClick: (view: View, data: Song) -> Unit,
+    ) : HomeAdapter<Song, RecyclerView.ViewHolder>() {
+        override fun getItemCount(): Int {
+            return if (data.isNotEmpty()) {
+                data.size + 1 // Make space for the play/shuffle header
+            } else {
+                data.size
+            }
+        }
+
+        override fun getItemViewType(position: Int): Int {
+            return if (position == 0) {
+                PLAY_ITEM_TYPE
+            } else {
+                SongViewHolder.ITEM_TYPE
+            }
+        }
+
+        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
+            return when (viewType) {
+                PLAY_ITEM_TYPE -> PlayViewHolder(
+                    ItemPlayShuffleBinding.inflate(parent.context.inflater)
+                )
+
+                SongViewHolder.ITEM_TYPE -> SongViewHolder.from(
+                    parent.context, doOnClick, doOnLongClick
+                )
+
+                else -> error("Invalid viewholder item type.")
+            }
+        }
+
+        override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
+            if (holder is SongViewHolder) {
+                holder.bind(data[position - 1])
+            }
+        }
+    }
+
+    private inner class PlayViewHolder(
+        binding: ItemPlayShuffleBinding
+    ) : RecyclerView.ViewHolder(binding.root) {
+        init {
+            // Force the layout to *actually* be the screen width.
+            // We can't inherit BaseViewHolder here since this ViewHolder isn't really connected
+            // to an item.
+            binding.root.layoutParams = RecyclerView.LayoutParams(
+                RecyclerView.LayoutParams.MATCH_PARENT, RecyclerView.LayoutParams.WRAP_CONTENT
+            )
+
+            binding.playButton.setOnClickListener {
+                playbackModel.playAll()
+            }
+
+            binding.shuffleButton.setOnClickListener {
+                playbackModel.shuffleAll()
+            }
+        }
+    }
+
+    companion object {
+        const val PLAY_ITEM_TYPE = 0xA00E
+    }
+}

app/src/main/java/org/oxycblt/auxio/home/recycler/HomeAdapter.kt

@@ -1,43 +0,0 @@
-/*
- * Copyright (c) 2021 Auxio Project
- * HomeAdapter.kt is part of Auxio.
- *
- * 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.home.recycler
-
-import android.annotation.SuppressLint
-import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.music.BaseModel
-
-/**
- * A base class that implements an [updateData] that is required across [SongsAdapter] and [ParentAdapter]
- */
-abstract class HomeAdapter<T : BaseModel> : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
-    protected var data = listOf<BaseModel>()
-
-    /**
-     * Update the data with [newData]. [notifyDataSetChanged] will be called.
-     */
-    @SuppressLint("NotifyDataSetChanged")
-    fun updateData(newData: List<BaseModel>) {
-        data = newData
-
-        // I would use ListAdapter instead of this inefficient invalidate call, but they still
-        // haven't fixed the issue where ListAdapter's calculations will cause wild scrolling
-        // for basically no reason.
-        notifyDataSetChanged()
-    }
-}

app/src/main/java/org/oxycblt/auxio/home/recycler/ParentAdapter.kt

@@ -1,75 +0,0 @@
-/*
- * Copyright (c) 2021 Auxio Project
- * ParentAdapter.kt is part of Auxio.
- *
- * 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.home.recycler
-
-import android.view.View
-import android.view.ViewGroup
-import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.music.Album
-import org.oxycblt.auxio.music.Artist
-import org.oxycblt.auxio.music.Genre
-import org.oxycblt.auxio.music.Parent
-import org.oxycblt.auxio.ui.AlbumViewHolder
-import org.oxycblt.auxio.ui.ArtistViewHolder
-import org.oxycblt.auxio.ui.GenreViewHolder
-
-/**
- * A universal adapter for displaying [Parent] data.
- */
-class ParentAdapter(
-    private val doOnClick: (data: Parent) -> Unit,
-    private val doOnLongClick: (view: View, data: Parent) -> Unit,
-) : HomeAdapter<Parent>() {
-    override fun getItemCount(): Int = data.size
-
-    override fun getItemViewType(position: Int): Int {
-        return when (data[position]) {
-            is Genre -> GenreViewHolder.ITEM_TYPE
-            is Artist -> ArtistViewHolder.ITEM_TYPE
-            is Album -> AlbumViewHolder.ITEM_TYPE
-            else -> error("Unsupported item ${data[position]::class.simpleName}")
-        }
-    }
-
-    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 (val item = data[position]) {
-            is Genre -> (holder as GenreViewHolder).bind(item)
-            is Artist -> (holder as ArtistViewHolder).bind(item)
-            is Album -> (holder as AlbumViewHolder).bind(item)
-        }
-    }
-}

app/src/main/java/org/oxycblt/auxio/home/recycler/SongsAdapter.kt

@@ -1,98 +0,0 @@
-/*
- * Copyright (c) 2021 Auxio Project
- * HomeAdapter.kt is part of Auxio.
- *
- * 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.home.recycler
-
-import android.view.View
-import android.view.ViewGroup
-import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.databinding.ItemPlayShuffleBinding
-import org.oxycblt.auxio.music.Song
-import org.oxycblt.auxio.playback.PlaybackViewModel
-import org.oxycblt.auxio.ui.SongViewHolder
-import org.oxycblt.auxio.util.inflater
-
-/**
- * An adapter for displaying a song list with a special play/shuffle header.
- * Note that the data for the play/pause icon does not need to be included with the data
- * you are submitting. It is automatically handled by the adapter.
- * TODO: Maybe extend play/shuffle to all items?
- */
-class SongsAdapter(
-    private val doOnClick: (data: Song) -> Unit,
-    private val doOnLongClick: (view: View, data: Song) -> Unit,
-    private val playbackModel: PlaybackViewModel
-) : HomeAdapter<Song>() {
-    override fun getItemCount(): Int = if
-    (data.isEmpty()) 0 // Account for the play/shuffle viewholder
-    else
-        data.size + 1
-
-    override fun getItemViewType(position: Int): Int {
-        return if (position == 0) {
-            PLAY_ITEM_TYPE
-        } else {
-            SongViewHolder.ITEM_TYPE
-        }
-    }
-
-    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
-        return when (viewType) {
-            PLAY_ITEM_TYPE -> PlayViewHolder(
-                ItemPlayShuffleBinding.inflate(parent.context.inflater)
-            )
-
-            SongViewHolder.ITEM_TYPE -> SongViewHolder.from(
-                parent.context, doOnClick, doOnLongClick
-            )
-
-            else -> error("Invalid viewholder item type.")
-        }
-    }
-
-    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
-        if (holder is SongViewHolder) {
-            holder.bind(data[position - 1] as Song)
-        }
-    }
-
-    private inner class PlayViewHolder(
-        binding: ItemPlayShuffleBinding
-    ) : RecyclerView.ViewHolder(binding.root) {
-        init {
-            // Force the layout to *actually* be the screen width.
-            // We can't inherit BaseViewHolder here since this ViewHolder isn't really connected
-            // to an item.
-            binding.root.layoutParams = RecyclerView.LayoutParams(
-                RecyclerView.LayoutParams.MATCH_PARENT, RecyclerView.LayoutParams.WRAP_CONTENT
-            )
-
-            binding.playButton.setOnClickListener {
-                playbackModel.playAll()
-            }
-
-            binding.shuffleButton.setOnClickListener {
-                playbackModel.shuffleAll()
-            }
-        }
-    }
-
-    companion object {
-        const val PLAY_ITEM_TYPE = 0xA00E
-    }
-}

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

@@ -305,7 +305,7 @@ class MusicLoader(private val context: Context) {
         // Songs that don't have a genre will be thrown into an unknown genre.
 
         val unknownGenre = Genre(
-            id = -2,
+            id = Long.MIN_VALUE,
             name = context.getString(R.string.def_genre)
         )
 
@@ -315,7 +315,7 @@ class MusicLoader(private val context: Context) {
             }
         }
 
-        if (unknownGenre.songs.isEmpty()) {
+        if (unknownGenre.songs.isNotEmpty()) {
             genres.add(unknownGenre)
         }
     }