WIP - Seamless transfer support

Author: dturner

app/src/main/AndroidManifest.xml

@@ -92,6 +92,8 @@
             </intent-filter>
         </service>
 
+        <receiver android:name="androidx.mediarouter.media.MediaTransferReceiver" />
+
     </application>
 
 </manifest>

app/src/main/java/com/example/android/uamp/MainActivity.kt

@@ -23,6 +23,11 @@ import android.view.Menu
 import androidx.activity.viewModels
 import androidx.appcompat.app.AppCompatActivity
 import androidx.lifecycle.Observer
+import androidx.lifecycle.ViewModelProviders
+import androidx.mediarouter.media.MediaControlIntent
+import androidx.mediarouter.media.MediaRouteSelector
+import androidx.mediarouter.media.MediaRouter
+import androidx.mediarouter.media.MediaRouterParams
 import com.example.android.uamp.fragments.MediaItemFragment
 import com.example.android.uamp.media.MusicService
 import com.example.android.uamp.utils.Event
@@ -31,12 +36,16 @@ import com.example.android.uamp.viewmodels.MainActivityViewModel
 import com.google.android.gms.cast.framework.CastButtonFactory
 import com.google.android.gms.cast.framework.CastContext
 
+
 class MainActivity : AppCompatActivity() {
 
     private val viewModel by viewModels<MainActivityViewModel> {
         InjectorUtils.provideMainActivityViewModel(this)
     }
     private var castContext: CastContext? = null
+    private lateinit var selector: MediaRouteSelector
+    private lateinit var router: MediaRouter
+
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -47,6 +56,16 @@ class MainActivity : AppCompatActivity() {
 
         setContentView(R.layout.activity_main)
 
+        router = MediaRouter.getInstance(this)
+        selector = MediaRouteSelector.Builder()
+            .addControlCategory(MediaControlIntent.CATEGORY_REMOTE_PLAYBACK)
+            .build()
+        router.routerParams = MediaRouterParams.Builder().setTransferToLocalEnabled(true).build()
+        router.addCallback(
+            selector, MediaRouterCallback(),
+            MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY
+        )
+
         // Since UAMP is a music player, the volume controls should adjust the music volume while
         // in the app.
         volumeControlStream = AudioManager.STREAM_MUSIC
@@ -114,4 +133,20 @@ class MainActivity : AppCompatActivity() {
     private fun getBrowseFragment(mediaId: String): MediaItemFragment? {
         return supportFragmentManager.findFragmentByTag(mediaId) as MediaItemFragment?
     }
+
+    private inner class MediaRouterCallback : MediaRouter.Callback() {
+        override fun onRouteSelected(
+            router: MediaRouter,
+            route: MediaRouter.RouteInfo,
+            reason: Int
+        ) {
+            if (reason == MediaRouter.UNSELECT_REASON_ROUTE_CHANGED) {
+                Log.d(TAG, "Unselected because route changed, continue playback")
+            } else if (reason == MediaRouter.UNSELECT_REASON_STOPPED) {
+                Log.d(TAG, "Unselected because route was stopped, stop playback")
+            }
+        }
+    }
 }
+
+private const val TAG = "MainActivity"

build.gradle

@@ -28,6 +28,7 @@ buildscript {
         androidx_car_version = '1.0.0-alpha7'
         androidx_core_ktx_version = '1.3.1'
         androidx_media_version = '1.0.1'
+        androidx_mediarouter_version = '1.2.0-rc01'
         androidx_preference_version = '1.1.1'
         androidx_test_runner_version = '1.3.0'
         arch_lifecycle_version = '2.2.0'

common/build.gradle

@@ -51,6 +51,7 @@ dependencies {
     api "org.jetbrains.kotlinx:kotlinx-coroutines-android:$kotlin_coroutines_version"
 
     api "androidx.media:media:$androidx_media_version"
+    implementation "androidx.mediarouter:mediarouter:$androidx_mediarouter_version"
 
     api "com.google.code.gson:gson:$gson_version"