Add navigation to LibraryFragment

Add navigiation to LibraryFragment. This navigation is nested so that one can still move through the ViewPager, which will certainly have no problems later on. /s

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

@@ -0,0 +1,37 @@
+package org.oxycblt.auxio.detail
+
+import android.os.Bundle
+import android.util.Log
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.databinding.DataBindingUtil
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.databinding.FragmentArtistDetailBinding
+import org.oxycblt.auxio.music.MusicViewModel
+
+class ArtistDetailFragment : Fragment() {
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        val binding = DataBindingUtil.inflate<FragmentArtistDetailBinding>(
+            inflater, R.layout.fragment_artist_detail, container, false
+        )
+
+        // I honestly don't want to turn of the any data classes into a parcelables due to how
+        // many lists they store, so just pick up the artist id and find it from musicModel.
+        val musicModel: MusicViewModel by activityViewModels()
+        val artistId = ArtistDetailFragmentArgs.fromBundle(requireArguments()).artistId
+
+        binding.artist = musicModel.artists.value?.find { it.id == artistId }
+
+        Log.d(this::class.simpleName, "Fragment created.")
+
+        return binding.root
+    }
+}

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

@@ -5,21 +5,17 @@ import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import androidx.activity.OnBackPressedCallback
 import androidx.databinding.DataBindingUtil
 import androidx.fragment.app.Fragment
-import androidx.fragment.app.activityViewModels
+import androidx.navigation.NavController
+import androidx.navigation.fragment.NavHostFragment
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.databinding.FragmentLibraryBinding
-import org.oxycblt.auxio.library.adapters.ArtistAdapter
-import org.oxycblt.auxio.music.MusicViewModel
-import org.oxycblt.auxio.recycler.ClickListener
-import org.oxycblt.auxio.recycler.applyDivider
 
 class LibraryFragment : Fragment() {
 
-    private val musicModel: MusicViewModel by activityViewModels {
+    private var navController: NavController? = null
-        MusicViewModel.Factory(requireActivity().application)
-    }
 
     override fun onCreateView(
         inflater: LayoutInflater,
@@ -30,17 +26,44 @@ class LibraryFragment : Fragment() {
             inflater, R.layout.fragment_library, container, false
         )
 
-        binding.libraryRecycler.adapter = ArtistAdapter(
+        requireActivity().onBackPressedDispatcher.addCallback(
-            musicModel.artists.value!!,
+            viewLifecycleOwner, callback
-            ClickListener { artist ->
-                Log.d(this::class.simpleName, artist.name)
-            }
         )
-        binding.libraryRecycler.applyDivider()
+
-        binding.libraryRecycler.setHasFixedSize(true)
+        val navHost = childFragmentManager.findFragmentById(R.id.nav_host) as? NavHostFragment
+        navController = navHost?.navController
 
         Log.d(this::class.simpleName, "Fragment created.")
 
         return binding.root
     }
+
+    override fun onResume() {
+        super.onResume()
+
+        callback.isEnabled = true
+    }
+
+    override fun onPause() {
+        super.onPause()
+        callback.isEnabled = false
+    }
+
+    val callback = object : OnBackPressedCallback(false) {
+
+        override fun handleOnBackPressed() {
+
+            // If at the root of the navigation, perform onBackPressed from the main activity.
+            if (navController?.currentDestination?.id == navController?.graph?.startDestination) {
+                // Disable the callback as it will get caught in an infinite loop otherwise.
+                isEnabled = false
+
+                requireActivity().onBackPressed()
+
+                isEnabled = true
+            } else {
+                navController?.navigateUp()
+            }
+        }
+    }
 }

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

@@ -0,0 +1,49 @@
+package org.oxycblt.auxio.library
+
+import android.os.Bundle
+import android.util.Log
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.databinding.DataBindingUtil
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
+import androidx.navigation.fragment.findNavController
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.databinding.FragmentLibraryListBinding
+import org.oxycblt.auxio.library.adapters.ArtistAdapter
+import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.recycler.ClickListener
+import org.oxycblt.auxio.recycler.applyDivider
+
+class LibraryListFragment : Fragment() {
+
+    private val musicModel: MusicViewModel by activityViewModels {
+        MusicViewModel.Factory(requireActivity().application)
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        val binding = DataBindingUtil.inflate<FragmentLibraryListBinding>(
+            inflater, R.layout.fragment_library_list, container, false
+        )
+
+        binding.libraryRecycler.adapter = ArtistAdapter(
+            musicModel.artists.value!!,
+            ClickListener { artist ->
+                findNavController().navigate(
+                    LibraryListFragmentDirections.actionShowArtist(artist.id)
+                )
+            }
+        )
+        binding.libraryRecycler.applyDivider()
+        binding.libraryRecycler.setHasFixedSize(true)
+
+        Log.d(this::class.simpleName, "Fragment created.")
+
+        return binding.root
+    }
+}

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

@@ -3,7 +3,7 @@ package org.oxycblt.auxio.library.adapters
 import android.view.LayoutInflater
 import android.view.ViewGroup
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.databinding.AlbumItemBinding
+import org.oxycblt.auxio.databinding.ItemAlbumBinding
 import org.oxycblt.auxio.music.models.Album
 import org.oxycblt.auxio.recycler.ClickListener
 import org.oxycblt.auxio.recycler.viewholders.AlbumViewHolder
@@ -16,7 +16,7 @@ class AlbumAdapter(
     override fun getItemCount(): Int = data.size
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): AlbumViewHolder {
-        val binding = AlbumItemBinding.inflate(LayoutInflater.from(parent.context))
+        val binding = ItemAlbumBinding.inflate(LayoutInflater.from(parent.context))
 
         // Force the item to *actually* be the screen width so ellipsizing can work.
         binding.root.layoutParams = RecyclerView.LayoutParams(

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

@@ -3,7 +3,7 @@ package org.oxycblt.auxio.library.adapters
 import android.view.LayoutInflater
 import android.view.ViewGroup
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.databinding.ArtistItemBinding
+import org.oxycblt.auxio.databinding.ItemArtistBinding
 import org.oxycblt.auxio.music.models.Artist
 import org.oxycblt.auxio.recycler.ClickListener
 import org.oxycblt.auxio.recycler.viewholders.ArtistViewHolder
@@ -16,7 +16,7 @@ class ArtistAdapter(
     override fun getItemCount(): Int = data.size
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ArtistViewHolder {
-        val binding = ArtistItemBinding.inflate(LayoutInflater.from(parent.context))
+        val binding = ItemArtistBinding.inflate(LayoutInflater.from(parent.context))
 
         // Force the item to *actually* be the screen width so ellipsizing can work.
         binding.root.layoutParams = RecyclerView.LayoutParams(

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

@@ -20,7 +20,7 @@ import org.oxycblt.auxio.music.processing.MusicLoader
 import org.oxycblt.auxio.music.processing.MusicLoaderResponse
 import org.oxycblt.auxio.music.processing.MusicSorter
 
-// Storage for music data.
+// ViewModel for music storage. May also be a god object.
 class MusicViewModel(private val app: Application) : ViewModel() {
 
     // Coroutine

app/src/main/java/org/oxycblt/auxio/music/models/Artist.kt

@@ -1,6 +1,6 @@
 package org.oxycblt.auxio.music.models
 
-// Abstraction for mAlbums
+// Abstraction for albums
 data class Artist(
     val id: Long = 0,
     var name: String = "",

app/src/main/java/org/oxycblt/auxio/recycler/viewholders/AlbumViewHolder.kt

@@ -1,12 +1,12 @@
 package org.oxycblt.auxio.recycler.viewholders
 
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.databinding.AlbumItemBinding
+import org.oxycblt.auxio.databinding.ItemAlbumBinding
 import org.oxycblt.auxio.music.models.Album
 
 // Generic ViewHolder for an album
 class AlbumViewHolder(
-    private val binding: AlbumItemBinding
+    private val binding: ItemAlbumBinding
 ) : RecyclerView.ViewHolder(binding.root) {
 
     // Bind the view w/new data

app/src/main/java/org/oxycblt/auxio/recycler/viewholders/ArtistViewHolder.kt

@@ -1,12 +1,12 @@
 package org.oxycblt.auxio.recycler.viewholders
 
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.databinding.ArtistItemBinding
+import org.oxycblt.auxio.databinding.ItemArtistBinding
 import org.oxycblt.auxio.music.models.Artist
 
 // Generic ViewHolder for an album
 class ArtistViewHolder(
-    private val binding: ArtistItemBinding
+    private val binding: ItemArtistBinding
 ) : RecyclerView.ViewHolder(binding.root) {
 
     // Bind the view w/new data

app/src/main/java/org/oxycblt/auxio/recycler/viewholders/SongViewHolder.kt

@@ -1,12 +1,12 @@
 package org.oxycblt.auxio.recycler.viewholders
 
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.databinding.SongItemBinding
+import org.oxycblt.auxio.databinding.ItemSongBinding
 import org.oxycblt.auxio.music.models.Song
 
 // Generic ViewHolder for a song
 class SongViewHolder(
-    private val binding: SongItemBinding
+    private val binding: ItemSongBinding
 ) : RecyclerView.ViewHolder(binding.root) {
 
     // Bind the view w/new data

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

@@ -3,7 +3,7 @@ package org.oxycblt.auxio.songs
 import android.view.LayoutInflater
 import android.view.ViewGroup
 import androidx.recyclerview.widget.RecyclerView
-import org.oxycblt.auxio.databinding.SongItemBinding
+import org.oxycblt.auxio.databinding.ItemSongBinding
 import org.oxycblt.auxio.music.models.Song
 import org.oxycblt.auxio.recycler.ClickListener
 import org.oxycblt.auxio.recycler.viewholders.SongViewHolder
@@ -16,7 +16,7 @@ class SongAdapter(
     override fun getItemCount(): Int = data.size
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): SongViewHolder {
-        val binding = SongItemBinding.inflate(LayoutInflater.from(parent.context))
+        val binding = ItemSongBinding.inflate(LayoutInflater.from(parent.context))
 
         // Force the item to *actually* be the screen width so ellipsizing can work.
         binding.root.layoutParams = RecyclerView.LayoutParams(

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

@@ -12,8 +12,7 @@
 
     <androidx.constraintlayout.widget.ConstraintLayout
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
+        android:layout_height="match_parent">
-        android:animateLayoutChanges="true">
 
         <androidx.viewpager2.widget.ViewPager2
             android:id="@+id/view_pager"

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

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <data>
+
+        <variable
+            name="artist"
+            type="org.oxycblt.auxio.music.models.Artist" />
+    </data>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical">
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@{artist.name}" />
+    </LinearLayout>
+</layout>

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

@@ -1,12 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
-<layout xmlns:app="http://schemas.android.com/apk/res-auto"
+<layout xmlns:android="http://schemas.android.com/apk/res/android"
-    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">
 
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:animateLayoutChanges="true"
         android:orientation="vertical">
 
         <androidx.appcompat.widget.Toolbar
@@ -19,13 +18,13 @@
             app:title="@string/title_library_fragment"
             tools:titleTextColor="@color/blue" />
 
-        <androidx.recyclerview.widget.RecyclerView
+        <androidx.fragment.app.FragmentContainerView
-            android:id="@+id/library_recycler"
+            android:id="@+id/nav_host"
+            android:name="androidx.navigation.fragment.NavHostFragment"
             android:layout_width="match_parent"
             android:layout_height="0dp"
             android:layout_weight="1"
-            app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
+            app:defaultNavHost="false"
-            tools:listitem="@layout/album_item" />
+            app:navGraph="@navigation/nav_library" />
-
     </LinearLayout>
 </layout>

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

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <FrameLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent">
+
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/library_recycler"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
+            tools:listitem="@layout/item_album" />
+
+    </FrameLayout>
+</layout>

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

@@ -14,8 +14,7 @@
 
     <androidx.constraintlayout.widget.ConstraintLayout
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
+        android:layout_height="match_parent">
-        android:animateLayoutChanges="true">
 
         <ProgressBar
             android:id="@+id/loading_bar"

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

@@ -6,7 +6,6 @@
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:animateLayoutChanges="true"
         android:orientation="vertical">
 
         <androidx.appcompat.widget.Toolbar
@@ -25,7 +24,7 @@
             android:layout_height="0dp"
             android:layout_weight="1"
             app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
-            tools:listitem="@layout/song_item" />
+            tools:listitem="@layout/item_song" />
 
     </LinearLayout>
 </layout>

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

@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <data>
+
+        <variable
+            name="album"
+            type="org.oxycblt.auxio.music.models.Album" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:background="@drawable/ripple"
+        android:clickable="true"
+        android:focusable="true"
+        android:padding="@dimen/padding_medium">
+
+        <ImageView
+            android:id="@+id/cover"
+            android:layout_width="@dimen/cover_size_normal"
+            android:layout_height="@dimen/cover_size_normal"
+            app:coverArt="@{album}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent"
+            tools:src="@tools:sample/backgrounds/scenic"
+            tools:ignore="ContentDescription" />
+
+        <TextView
+            android:id="@+id/album_name"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="@dimen/margin_medium"
+            android:text="@{album.name}"
+            android:textAppearance="?android:attr/textAppearanceListItem"
+            android:textColor="?android:attr/textColorPrimary"
+            android:ellipsize="end"
+            android:maxLines="1"
+            app:layout_constraintBottom_toTopOf="@+id/song_count"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toEndOf="@+id/cover"
+            app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintVertical_chainStyle="packed"
+            tools:text="Album Name" />
+
+        <TextView
+            android:id="@+id/song_count"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="@dimen/margin_medium"
+            android:textAppearance="?android:attr/textAppearanceListItemSecondary"
+            android:textColor="?android:attr/textColorSecondary"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintStart_toEndOf="@+id/cover"
+            app:layout_constraintTop_toBottomOf="@+id/album_name"
+            app:songCount="@{album}"
+            tools:text="10 Songs" />
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>

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

@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <data>
+
+        <variable
+            name="artist"
+            type="org.oxycblt.auxio.music.models.Artist" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:background="@drawable/ripple"
+        android:clickable="true"
+        android:focusable="true"
+        android:padding="@dimen/padding_medium">
+
+        <ImageView
+            android:id="@+id/artist_image"
+            android:layout_width="@dimen/cover_size_normal"
+            android:layout_height="@dimen/cover_size_normal"
+            app:artistImage="@{artist}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent"
+            tools:src="@tools:sample/backgrounds/scenic"
+            tools:ignore="ContentDescription" />
+
+        <TextView
+            android:id="@+id/artist_name"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:ellipsize="end"
+            android:maxLines="1"
+            android:text="@{artist.name}"
+            android:layout_marginStart="@dimen/margin_medium"
+            android:textAppearance="?android:attr/textAppearanceListItem"
+            android:textColor="?android:attr/textColorPrimary"
+            app:layout_constraintBottom_toTopOf="@+id/album_song_count"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toEndOf="@+id/artist_image"
+            app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintVertical_chainStyle="packed"
+            tools:text="Artist Name" />
+
+        <TextView
+            android:id="@+id/album_song_count"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textAppearance="?android:attr/textAppearanceListItemSecondary"
+            android:layout_marginStart="@dimen/margin_medium"
+            android:textColor="?android:attr/textColorSecondary"
+            app:artistCounts="@{artist}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintStart_toEndOf="@+id/artist_image"
+            app:layout_constraintTop_toBottomOf="@+id/artist_name"
+            tools:text="2 Albums, 20 Songs" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>

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

@@ -0,0 +1,81 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <data>
+
+        <variable
+            name="song"
+            type="org.oxycblt.auxio.music.models.Song" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:background="@drawable/ripple"
+        android:clickable="true"
+        android:focusable="true"
+        android:padding="@dimen/padding_medium">
+
+        <ImageView
+            android:id="@+id/cover"
+            android:layout_width="@dimen/cover_size_compact"
+            android:layout_height="@dimen/cover_size_compact"
+            app:coverArt="@{song}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent"
+            tools:src="@tools:sample/backgrounds/scenic"
+            tools:ignore="ContentDescription" />
+
+        <TextView
+            android:id="@+id/song_name"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="@dimen/margin_medium"
+            android:layout_marginEnd="@dimen/margin_medium"
+            android:ellipsize="end"
+            android:maxLines="1"
+            android:text="@{song.name}"
+            android:textAppearance="?android:attr/textAppearanceListItem"
+            android:textColor="?android:attr/textColorPrimary"
+            app:layout_constraintBottom_toTopOf="@+id/song_info"
+            app:layout_constraintEnd_toStartOf="@+id/duration"
+            app:layout_constraintStart_toEndOf="@+id/cover"
+            app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintVertical_chainStyle="packed"
+            tools:text="Song Name" />
+
+        <TextView
+            android:id="@+id/song_info"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="@dimen/margin_medium"
+            android:layout_marginEnd="@dimen/margin_medium"
+            android:ellipsize="end"
+            android:maxLines="1"
+            android:textAppearance="?android:attr/textAppearanceListItemSecondary"
+            android:textColor="?android:attr/textColorSecondary"
+            android:text="@{@string/format_song_info(song.album.artist.name, song.album.name)}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toStartOf="@+id/duration"
+            app:layout_constraintStart_toEndOf="@+id/cover"
+            app:layout_constraintTop_toBottomOf="@+id/song_name"
+            tools:text="Artist / Album" />
+
+        <TextView
+            android:id="@+id/duration"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:gravity="center"
+            android:text="@{song.formattedDuration}"
+            android:textAppearance="?android:attr/textAppearanceListItemSecondary"
+            android:textColor="?android:attr/textColorTertiary"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toTopOf="parent"
+            tools:text="16:16" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>

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

@@ -0,0 +1,26 @@
+<?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_library"
+    app:startDestination="@id/libraryListFragment">
+
+    <fragment
+        android:id="@+id/libraryListFragment"
+        android:name="org.oxycblt.auxio.library.LibraryListFragment"
+        android:label="LibraryFragment"
+        tools:layout="@layout/fragment_library_list">
+        <action
+            android:id="@+id/action_show_artist"
+            app:destination="@id/artistDetailFragment" />
+    </fragment>
+    <fragment
+        android:id="@+id/artistDetailFragment"
+        android:name="org.oxycblt.auxio.detail.ArtistDetailFragment"
+        android:label="ArtistDetailFragment"
+        tools:layout="@layout/fragment_artist_detail">
+        <argument
+            android:name="artistId"
+            app:argType="long" />
+    </fragment>
+</navigation>