Add basic playback functionaliity

Implement ExoPlayer in a basic form so that songs can be actually played.

app/build.gradle

@@ -32,6 +32,10 @@ android {
     kotlinOptions {
         jvmTarget = "1.8"
     }
+
+    compileOptions {
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
 }
 
 configurations {
@@ -76,6 +80,9 @@ dependencies {
     // Lint
     ktlint "com.pinterest:ktlint:0.37.2"
 
+    // ExoPlayer
+    implementation 'com.google.android.exoplayer:exoplayer-core:2.12.1'
+
     // Memory Leak checking
     debugImplementation 'com.squareup.leakcanary:leakcanary-android:2.4'
 }

app/src/main/AndroidManifest.xml

@@ -3,6 +3,8 @@
     package="org.oxycblt.auxio">
 
     <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+    <uses-permission android:name="android.permission.WAKE_LOCK" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
 
     <application
         android:allowBackup="true"
@@ -21,6 +23,10 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <service android:name=".playback.PlaybackService"
+            android:icon="@drawable/ic_launcher_foreground"
+            android:description="@string/description_service_playback"
+            android:stopWithTask="false"/>
     </application>
 
 </manifest>

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

@@ -23,7 +23,9 @@ import org.oxycblt.auxio.theme.getTransparentAccent
 import org.oxycblt.auxio.theme.toColor
 
 class MainFragment : Fragment() {
-    private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val playbackModel: PlaybackViewModel by activityViewModels {
+        PlaybackViewModel.Factory(requireContext())
+    }
 
     private val shownFragments = listOf(0, 1)
     private val tabIcons = listOf(

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

@@ -22,7 +22,9 @@ class AlbumDetailFragment : Fragment() {
 
     private val args: AlbumDetailFragmentArgs by navArgs()
     private val detailModel: DetailViewModel by activityViewModels()
-    private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val playbackModel: PlaybackViewModel by activityViewModels {
+        PlaybackViewModel.Factory(requireContext())
+    }
 
     override fun onCreateView(
         inflater: LayoutInflater,

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

@@ -20,7 +20,9 @@ import org.oxycblt.auxio.theme.disable
 class ArtistDetailFragment : Fragment() {
     private val args: ArtistDetailFragmentArgs by navArgs()
     private val detailModel: DetailViewModel by activityViewModels()
-    private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val playbackModel: PlaybackViewModel by activityViewModels {
+        PlaybackViewModel.Factory(requireContext())
+    }
 
     override fun onCreateView(
         inflater: LayoutInflater,

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

@@ -21,7 +21,9 @@ class GenreDetailFragment : Fragment() {
 
     private val args: GenreDetailFragmentArgs by navArgs()
     private val detailModel: DetailViewModel by activityViewModels()
-    private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val playbackModel: PlaybackViewModel by activityViewModels {
+        PlaybackViewModel.Factory(requireContext())
+    }
 
     override fun onCreateView(
         inflater: LayoutInflater,

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

@@ -35,7 +35,9 @@ import org.oxycblt.auxio.theme.resolveAttr
 class LibraryFragment : Fragment(), SearchView.OnQueryTextListener {
 
     private val libraryModel: LibraryViewModel by activityViewModels()
-    private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val playbackModel: PlaybackViewModel by activityViewModels {
+        PlaybackViewModel.Factory(requireContext())
+    }
 
     override fun onCreateView(
         inflater: LayoutInflater,

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

@@ -22,7 +22,9 @@ import org.oxycblt.auxio.theme.toColor
 
 // TODO: Add a swipe-to-next-track function using a ViewPager
 class PlaybackFragment : Fragment(), SeekBar.OnSeekBarChangeListener {
-    private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val playbackModel: PlaybackViewModel by activityViewModels {
+        PlaybackViewModel.Factory(requireActivity().application)
+    }
 
     // TODO: Implement nav to artists/albums
     override fun onCreateView(

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

@@ -0,0 +1,47 @@
+package org.oxycblt.auxio.playback
+
+import android.app.Service
+import android.content.Intent
+import android.os.Binder
+import android.os.Build
+import android.os.IBinder
+import com.google.android.exoplayer2.MediaItem
+import com.google.android.exoplayer2.Player
+import com.google.android.exoplayer2.SimpleExoPlayer
+import org.oxycblt.auxio.music.Song
+import org.oxycblt.auxio.music.toURI
+
+class PlaybackService : Service(), Player.EventListener {
+    private val player: SimpleExoPlayer by lazy {
+        val p = SimpleExoPlayer.Builder(applicationContext).build()
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+            p.experimentalSetOffloadSchedulingEnabled(true)
+        }
+        p.addListener(this)
+        p
+    }
+
+    private val mBinder = LocalBinder()
+
+    override fun onBind(intent: Intent): IBinder {
+        return mBinder
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+
+        player.release()
+    }
+
+    fun playSong(song: Song) {
+        val item = MediaItem.fromUri(song.id.toURI())
+
+        player.setMediaItem(item)
+        player.prepare()
+        player.play()
+    }
+
+    inner class LocalBinder : Binder() {
+        fun getService() = this@PlaybackService
+    }
+}

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

@@ -1,10 +1,17 @@
 package org.oxycblt.auxio.playback
 
+import android.content.ComponentName
+import android.content.Context
+import android.content.Intent
+import android.content.ServiceConnection
+import android.os.IBinder
 import android.util.Log
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.Transformations
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import com.google.android.exoplayer2.Player
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
 import org.oxycblt.auxio.music.BaseModel
@@ -15,12 +22,12 @@ import org.oxycblt.auxio.music.toDuration
 import kotlin.random.Random
 import kotlin.random.Random.Default.nextLong
 
-// TODO: Adding to Queue
+// TODO: User managed queue
 // TODO: Add the playback service itself
 // TODO: Add loop control [From playback]
 // TODO: Implement persistence through Bundles [I want to keep my shuffles, okay?]
 // A ViewModel that acts as an intermediary between PlaybackService and the Playback Fragments.
-class PlaybackViewModel : ViewModel() {
+class PlaybackViewModel(private val context: Context) : ViewModel(), Player.EventListener {
     private val mCurrentSong = MutableLiveData<Song>()
     val currentSong: LiveData<Song> get() = mCurrentSong
 
@@ -53,6 +60,25 @@ class PlaybackViewModel : ViewModel() {
     private var mCanAnimate = false
     val canAnimate: Boolean get() = mCanAnimate
 
+    private lateinit var playbackService: PlaybackService
+    private var playbackIntent: Intent
+
+    private val connection = object : ServiceConnection {
+        override fun onServiceConnected(name: ComponentName, binder: IBinder) {
+            playbackService = (binder as PlaybackService.LocalBinder).getService()
+        }
+
+        override fun onServiceDisconnected(name: ComponentName) {
+            Log.d(this::class.simpleName, "Service disconnected.")
+        }
+    }
+
+    init {
+        playbackIntent = Intent(context, PlaybackService::class.java).also {
+            context.bindService(it, connection, Context.BIND_AUTO_CREATE)
+        }
+    }
+
     // Formatted variants of the duration
     val formattedCurrentDuration = Transformations.map(mCurrentDuration) {
         it.toDuration()
@@ -69,7 +95,6 @@ class PlaybackViewModel : ViewModel() {
 
     // Update the current song while changing the queue mode.
     fun update(song: Song, mode: PlaybackMode) {
-
         // Auxio doesn't support playing songs while swapping the mode to GENRE, as its impossible
         // to determine what genre a song has.
         if (mode == PlaybackMode.IN_GENRE) {
@@ -312,6 +337,8 @@ class PlaybackViewModel : ViewModel() {
         if (!mIsPlaying.value!!) {
             mIsPlaying.value = true
         }
+
+        playbackService.playSong(song)
     }
 
     // Generate a new shuffled queue.
@@ -383,4 +410,21 @@ class PlaybackViewModel : ViewModel() {
 
         return final
     }
+
+    override fun onCleared() {
+        super.onCleared()
+
+        context.unbindService(connection)
+    }
+
+    class Factory(private val context: Context) : ViewModelProvider.Factory {
+        @Suppress("unchecked_cast")
+        override fun <T : ViewModel?> create(modelClass: Class<T>): T {
+            if (modelClass.isAssignableFrom(PlaybackViewModel::class.java)) {
+                return PlaybackViewModel(context) as T
+            }
+
+            throw IllegalArgumentException("Unknown ViewModel class.")
+        }
+    }
 }

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

@@ -15,7 +15,9 @@ import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.theme.applyDivider
 
 class SongsFragment : Fragment() {
-    private val playbackModel: PlaybackViewModel by activityViewModels()
+    private val playbackModel: PlaybackViewModel by activityViewModels {
+        PlaybackViewModel.Factory(requireContext())
+    }
 
     override fun onCreateView(
         inflater: LayoutInflater,

app/src/main/res/drawable/ic_pause.xml

@@ -3,7 +3,8 @@
     android:width="32dp"
     android:height="32dp"
     android:viewportWidth="24"
-    android:viewportHeight="24">
+    android:viewportHeight="24"
+    android:tint="?android:attr/colorControlNormal">
     <path
         android:fillColor="@android:color/white"
         android:pathData="m 7.5,6 h 3 v 12 h -3 z m 9,0 h -3 v 12 h 3 z" />

app/src/main/res/drawable/ic_play.xml

@@ -3,7 +3,8 @@
     android:width="32dp"
     android:height="32dp"
     android:viewportWidth="24"
-    android:viewportHeight="24">
+    android:viewportHeight="24"
+    android:tint="?android:attr/colorControlNormal">
     <path
         android:fillColor="@android:color/white"
         android:pathData="M8.25,6L8.25,12L18.75,12L18.75,12ZM8.25,18L8.25,12L18.75,12L18.75,12Z" />

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

@@ -30,7 +30,6 @@
             android:layout_height="?android:attr/actionBarSize"
             android:background="?android:attr/windowBackground"
             android:elevation="@dimen/elevation_normal"
-            app:popupTheme="@style/AppThemeOverlay.Popup"
             app:menu="@menu/menu_detail"
             app:titleTextAppearance="@style/TextAppearance.Toolbar.Header"
             app:navigationIcon="@drawable/ic_back"

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

@@ -1,13 +1,14 @@
 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item
+        android:id="@+id/action_play"
+        android:title="@string/label_play"
+        android:icon="@drawable/ic_play"
+        app:showAsAction="ifRoom" />
     <item
         android:id="@+id/action_shuffle"
         android:icon="@drawable/ic_shuffle"
         android:title="@string/label_shuffle"
         app:showAsAction="ifRoom" />
-    <item
-        android:id="@+id/action_play"
-        android:title="@string/label_play"
-        app:showAsAction="never" />
 </menu>

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

@@ -47,6 +47,7 @@
     <string name="description_skip_prev">Skip to last song</string>
     <string name="description_shuffle_on">Turn shuffle on</string>
     <string name="description_shuffle_off">Turn shuffle off</string>
+    <string name="description_service_playback">The music playback service for Auxio</string>
 
     <!-- Placeholder Namespace | Placeholder values -->
     <string name="placeholder_genre">Unknown Genre</string>