Switch from ViewPager to BottomNavigationView

Use BottomNavigationView as the main navigator of Auxio instead of a ViewPager + BottomNavigationView, primarily to fix some memory leaks and give Auxio a better UI design overall.

app/build.gradle

@@ -73,10 +73,9 @@ dependencies {
     implementation 'androidx.media:media:1.2.0'
 
     // Database
-    def room_version = '2.2.5'
+    def room_version = '2.3.0-alpha03'
     implementation "androidx.room:room-runtime:$room_version"
     kapt "androidx.room:room-compiler:$room_version"
-    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
     implementation "androidx.room:room-ktx:$room_version"
 
     // --- THIRD PARTY ---

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

@@ -1,22 +1,20 @@
 package org.oxycblt.auxio
 
+import android.content.res.ColorStateList
 import android.os.Bundle
 import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.core.content.ContextCompat
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
+import androidx.navigation.findNavController
+import androidx.navigation.fragment.NavHostFragment
 import androidx.navigation.fragment.findNavController
-import androidx.viewpager2.adapter.FragmentStateAdapter
+import androidx.navigation.ui.setupWithNavController
-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.MusicStore
 import org.oxycblt.auxio.playback.PlaybackViewModel
-import org.oxycblt.auxio.songs.SongsFragment
 import org.oxycblt.auxio.ui.accent
 import org.oxycblt.auxio.ui.getInactiveAlpha
 import org.oxycblt.auxio.ui.getTransparentAccent
@@ -52,40 +50,24 @@ class MainFragment : Fragment() {
             accent.first,
             getInactiveAlpha(accent.first)
         )
+        val navIconTints = ColorStateList(
+            arrayOf(
+                intArrayOf(-android.R.attr.state_checked),
+                intArrayOf(android.R.attr.state_checked)
+            ),
+            intArrayOf(colorInactive, colorActive)
+        )
 
         // --- UI SETUP ---
 
-        // TODO: Add nested viewpager navigation [If practical]
-
         binding.lifecycleOwner = this
-        binding.mainViewPager.adapter = PagerAdapter()
 
-        // Link the ViewPager & Tab View
+        binding.navBar.itemIconTintList = navIconTints
-        TabLayoutMediator(binding.mainTabs, binding.mainViewPager) { tab, position ->
+        binding.navBar.itemTextColor = navIconTints
-            tab.icon = ContextCompat.getDrawable(requireContext(), tabIcons[position])
+        ((childFragmentManager.findFragmentById(R.id.explore_nav_host) as NavHostFragment?))?.let {
-
+            // TODO: Add animation with BottomNavigationView navs
-            // Set the icon tint to deselected if its not the default tab
+            binding.navBar.setupWithNavController(it.findNavController())
-            if (position > 0) {
+        }
-                tab.icon?.setTint(colorInactive)
-            }
-        }.attach()
-
-        // Set up the selected/deselected colors
-        binding.mainTabs.addOnTabSelectedListener(
-            object : TabLayout.OnTabSelectedListener {
-
-                override fun onTabSelected(tab: TabLayout.Tab) {
-                    tab.icon?.setTint(colorActive)
-                }
-
-                override fun onTabUnselected(tab: TabLayout.Tab) {
-                    tab.icon?.setTint(colorInactive)
-                }
-
-                override fun onTabReselected(tab: TabLayout.Tab?) {
-                }
-            }
-        )
 
         // --- VIEWMODEL SETUP ---
 
@@ -107,35 +89,4 @@ class MainFragment : Fragment() {
 
         return binding.root
     }
-
-    private fun fragmentAt(position: Int): Fragment {
-        return when (position) {
-            0 -> LibraryFragment()
-            1 -> SongsFragment()
-
-            else -> SongsFragment()
-        }
-    }
-
-    private inner class PagerAdapter :
-        FragmentStateAdapter(childFragmentManager, viewLifecycleOwner.lifecycle) {
-        override fun getItemCount(): Int = shownFragments.size
-
-        override fun createFragment(position: Int): Fragment {
-            Log.d(this::class.simpleName, "Switching to fragment $position.")
-
-            if (shownFragments.contains(position)) {
-                return fragmentAt(position)
-            }
-
-            // If a fragment that shouldn't be shown is somehow shown anyway, just return
-            // its intended fragment.
-            Log.e(
-                this::class.simpleName,
-                "Attempted to index a fragment that shouldn't be shown."
-            )
-
-            return fragmentAt(position)
-        }
-    }
 }

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

@@ -6,7 +6,6 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import androidx.appcompat.widget.PopupMenu
-import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
 import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
@@ -20,7 +19,7 @@ import org.oxycblt.auxio.ui.applyDivider
 import org.oxycblt.auxio.ui.disable
 import org.oxycblt.auxio.ui.setupAlbumSongActions
 
-class AlbumDetailFragment : Fragment() {
+class AlbumDetailFragment : DetailFragment() {
 
     private val args: AlbumDetailFragmentArgs by navArgs()
     private val detailModel: DetailViewModel by activityViewModels()

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

@@ -5,7 +5,6 @@ import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
 import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
@@ -17,7 +16,7 @@ import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.applyDivider
 import org.oxycblt.auxio.ui.disable
 
-class ArtistDetailFragment : Fragment() {
+class ArtistDetailFragment : DetailFragment() {
     private val args: ArtistDetailFragmentArgs by navArgs()
     private val detailModel: DetailViewModel by activityViewModels()
     private val playbackModel: PlaybackViewModel by activityViewModels()
@@ -107,10 +106,4 @@ class ArtistDetailFragment : Fragment() {
 
         return binding.root
     }
-
-    override fun onResume() {
-        super.onResume()
-
-        detailModel.updateNavigationStatus(false)
-    }
 }

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

@@ -0,0 +1,44 @@
+package org.oxycblt.auxio.detail
+
+import android.os.Bundle
+import android.view.View
+import androidx.activity.OnBackPressedCallback
+import androidx.fragment.app.Fragment
+import androidx.navigation.fragment.findNavController
+
+/**
+ * A Base [Fragment] implementing a [OnBackPressedCallback] so that Auxio will navigate upwards
+ * instead of out of the app if a Detail Fragment is currently open.
+ * @author OxygenCobalt
+ */
+abstract class DetailFragment : Fragment() {
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner, callback)
+    }
+
+    override fun onResume() {
+        super.onResume()
+
+        callback.isEnabled = true
+    }
+
+    override fun onPause() {
+        super.onPause()
+        callback.isEnabled = false
+    }
+
+    private val callback = object : OnBackPressedCallback(false) {
+
+        override fun handleOnBackPressed() {
+            val navController = findNavController()
+            // Check if it's the root of nested fragments in this navhost
+            if (navController.currentDestination?.id == navController.graph.startDestination) {
+                isEnabled = false
+                requireActivity().onBackPressed()
+                isEnabled = true
+            } else {
+                navController.navigateUp()
+            }
+        }
+    }
+}

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

@@ -5,7 +5,6 @@ import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
 import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
@@ -17,7 +16,7 @@ import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.applyDivider
 import org.oxycblt.auxio.ui.disable
 
-class GenreDetailFragment : Fragment() {
+class GenreDetailFragment : DetailFragment() {
 
     private val args: GenreDetailFragmentArgs by navArgs()
     private val detailModel: DetailViewModel by activityViewModels()

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

@@ -203,9 +203,9 @@ class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
 
             findNavController().navigate(
                 when (baseModel) {
-                    is Genre -> MainFragmentDirections.actionShowGenre(baseModel.id)
+                    is Genre -> LibraryFragmentDirections.actionShowGenre(baseModel.id)
-                    is Artist -> MainFragmentDirections.actionShowArtist(baseModel.id)
+                    is Artist -> LibraryFragmentDirections.actionShowArtist(baseModel.id)
-                    is Album -> MainFragmentDirections.actionShowAlbum(baseModel.id, true)
+                    is Album -> LibraryFragmentDirections.actionShowAlbum(baseModel.id, true)
 
                     // If given model wasn't valid, then reset the navigation status
                     // and abort the navigation.

app/src/main/java/org/oxycblt/auxio/playback/queue/QueueDragCallback.kt

@@ -53,7 +53,11 @@ class QueueDragCallback(private val playbackModel: PlaybackViewModel) : ItemTouc
         viewHolder: RecyclerView.ViewHolder,
         target: RecyclerView.ViewHolder
     ): Boolean {
-        return playbackModel.moveQueueItems(viewHolder.adapterPosition, target.adapterPosition, queueAdapter)
+        return playbackModel.moveQueueItems(
+            viewHolder.adapterPosition,
+            target.adapterPosition,
+            queueAdapter
+        )
     }
 
     override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {

app/src/main/java/org/oxycblt/auxio/playback/state/PlaybackStateManager.kt

@@ -539,7 +539,10 @@ class PlaybackStateManager private constructor() {
         // If the parent was somehow dropped during saving, attempt to restore it.
         mSong?.let {
             if (mParent == null && mMode != PlaybackMode.ALL_SONGS) {
-                Log.d(this::class.simpleName, "Parent was corrupted while in mode $mMode. Attempting to restore.")
+                Log.d(
+                    this::class.simpleName,
+                    "Parent was corrupted while in mode $mMode. Attempting to restore."
+                )
                 mParent = when (mMode) {
                     PlaybackMode.IN_ARTIST -> it.album.artist
                     PlaybackMode.IN_ALBUM -> it.album

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

@@ -15,6 +15,8 @@
             type="org.oxycblt.auxio.playback.PlaybackViewModel" />
     </data>
 
+    <!-- TODO: Fix elevation not showing -->
+
     <androidx.constraintlayout.widget.ConstraintLayout
         android:animateLayoutChanges="true"
         android:background="@drawable/ui_ripple"

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

@@ -4,43 +4,46 @@
     xmlns:tools="http://schemas.android.com/tools"
     tools:context=".MainFragment">
 
-    <LinearLayout
+    <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/main_layout"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:animateLayoutChanges="true"
         android:orientation="vertical">
 
-        <androidx.viewpager2.widget.ViewPager2
+        <androidx.fragment.app.FragmentContainerView
-            android:id="@+id/main_view_pager"
+            android:id="@+id/explore_nav_host"
+            android:name="androidx.navigation.fragment.NavHostFragment"
             android:layout_width="match_parent"
             android:layout_height="0dp"
-            android:layout_weight="1" />
+            android:elevation="@dimen/elevation_normal"
+            app:layout_constraintBottom_toTopOf="@+id/compact_playback"
+            app:layout_constraintTop_toTopOf="parent"
+            app:navGraph="@navigation/nav_explore"
+            tools:layout="@layout/fragment_library" />
 
         <androidx.fragment.app.FragmentContainerView
             android:id="@+id/compact_playback"
+            android:name="org.oxycblt.auxio.playback.CompactPlaybackFragment"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:visibility="gone"
-            android:name="org.oxycblt.auxio.playback.CompactPlaybackFragment"
+            app:layout_constraintBottom_toTopOf="@+id/nav_bar"
-            android:elevation="@dimen/elevation_normal" />
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            tools:layout="@layout/fragment_compact_playback" />
 
-        <com.google.android.material.tabs.TabLayout
+        <com.google.android.material.bottomnavigation.BottomNavigationView
-            android:id="@+id/main_tabs"
+            android:id="@+id/nav_bar"
             android:layout_width="match_parent"
-            android:layout_height="@dimen/height_tab_menu"
+            android:layout_height="wrap_content"
-            android:layout_gravity="bottom"
+            android:background="@color/background"
-            android:background="?android:attr/windowBackground"
             android:elevation="@dimen/elevation_normal"
+            app:itemRippleColor="@color/selection_color"
             app:layout_constraintBottom_toBottomOf="parent"
-            app:tabGravity="fill"
+            app:layout_constraintEnd_toEndOf="parent"
-            app:tabIconTint="?attr/colorPrimary"
+            app:layout_constraintStart_toStartOf="parent"
-            app:tabIconTintMode="src_in"
+            app:menu="@menu/menu_nav" />
-            app:tabIndicator="@drawable/ui_indicator"
-            app:tabIndicatorColor="?attr/colorPrimary"
-            app:tabMode="fixed"
-            app:tabRippleColor="@color/selection_color"
-            tools:background="@color/control_color" />
 
-    </LinearLayout>
+    </androidx.constraintlayout.widget.ConstraintLayout>
 </layout>

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

@@ -46,7 +46,7 @@
             android:layout_margin="@dimen/margin_mid_large"
             android:contentDescription="@{@string/description_album_cover(song.name)}"
             android:outlineProvider="bounds"
-            android:elevation="4dp"
+            android:elevation="2dp"
             app:coverArt="@{song}"
             app:layout_constraintBottom_toTopOf="@+id/playback_song"
             app:layout_constraintDimensionRatio="1:1"

app/src/main/res/menu/menu_nav.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android">
+    <item
+        android:id="@+id/library_fragment"
+        android:title="@string/title_library_fragment"
+        android:icon="@drawable/ic_library" />
+    <item
+        android:id="@+id/songs_fragment"
+        android:title="@string/label_songs"
+        android:icon="@drawable/ic_song" />
+</menu>

app/src/main/res/navigation/nav_explore.xml

@@ -0,0 +1,92 @@
+<?xml version="1.0" encoding="utf-8"?>
+<navigation 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/nav_explore"
+    app:startDestination="@id/library_fragment">
+
+    <fragment
+        android:id="@+id/library_fragment"
+        android:name="org.oxycblt.auxio.library.LibraryFragment"
+        android:label="fragment_library"
+        tools:layout="@layout/fragment_library">
+        <action
+            android:id="@+id/action_show_genre"
+            app:enterAnim="@anim/nav_default_enter_anim"
+            app:exitAnim="@anim/nav_default_exit_anim"
+            app:popEnterAnim="@anim/nav_default_pop_enter_anim"
+            app:popExitAnim="@anim/nav_default_pop_exit_anim"
+            app:destination="@id/genre_detail_fragment" />
+        <action
+            android:id="@+id/action_show_artist"
+            app:enterAnim="@anim/nav_default_enter_anim"
+            app:exitAnim="@anim/nav_default_exit_anim"
+            app:popEnterAnim="@anim/nav_default_pop_enter_anim"
+            app:popExitAnim="@anim/nav_default_pop_exit_anim"
+            app:destination="@id/artist_detail_fragment" />
+        <action
+            android:id="@+id/action_show_album"
+            app:enterAnim="@anim/nav_default_enter_anim"
+            app:exitAnim="@anim/nav_default_exit_anim"
+            app:popEnterAnim="@anim/nav_default_pop_enter_anim"
+            app:popExitAnim="@anim/nav_default_pop_exit_anim"
+            app:destination="@id/album_detail_fragment" />
+    </fragment>
+    <fragment
+        android:id="@+id/artist_detail_fragment"
+        android:name="org.oxycblt.auxio.detail.ArtistDetailFragment"
+        android:label="ArtistDetailFragment"
+        tools:layout="@layout/fragment_artist_detail">
+        <argument
+            android:name="artistId"
+            app:argType="long" />
+        <action
+            android:id="@+id/action_show_album"
+            app:enterAnim="@anim/nav_default_enter_anim"
+            app:exitAnim="@anim/nav_default_exit_anim"
+            app:popEnterAnim="@anim/nav_default_pop_enter_anim"
+            app:popExitAnim="@anim/nav_default_pop_exit_anim"
+            app:destination="@id/album_detail_fragment"
+            app:launchSingleTop="true" />
+    </fragment>
+    <fragment
+        android:id="@+id/album_detail_fragment"
+        android:name="org.oxycblt.auxio.detail.AlbumDetailFragment"
+        android:label="AlbumDetailFragment"
+        tools:layout="@layout/fragment_album_detail">
+        <argument
+            android:name="albumId"
+            app:argType="long" />
+        <argument
+            android:name="enableParentNav"
+            app:argType="boolean" />
+        <action
+            android:id="@+id/action_show_parent_artist"
+            app:enterAnim="@anim/nav_default_enter_anim"
+            app:exitAnim="@anim/nav_default_exit_anim"
+            app:popEnterAnim="@anim/nav_default_pop_enter_anim"
+            app:popExitAnim="@anim/nav_default_pop_exit_anim"
+            app:destination="@id/artist_detail_fragment" />
+    </fragment>
+    <fragment
+        android:id="@+id/genre_detail_fragment"
+        android:name="org.oxycblt.auxio.detail.GenreDetailFragment"
+        android:label="GenreDetailFragment"
+        tools:layout="@layout/fragment_genre_detail">
+        <action
+            android:id="@+id/action_show_artist"
+            app:enterAnim="@anim/nav_default_enter_anim"
+            app:exitAnim="@anim/nav_default_exit_anim"
+            app:popEnterAnim="@anim/nav_default_pop_enter_anim"
+            app:popExitAnim="@anim/nav_default_pop_exit_anim"
+            app:destination="@id/artist_detail_fragment" />
+        <argument
+            android:name="genreId"
+            app:argType="long" />
+    </fragment>
+    <fragment
+        android:id="@+id/songs_fragment"
+        android:name="org.oxycblt.auxio.songs.SongsFragment"
+        android:label="fragment_songs"
+        tools:layout="@layout/fragment_songs" />
+</navigation>