[demo-compose] Add Activity lifecycle methods

Take care of releasing the player and re-initialising when returning to the app to prevent memory leaks.

Instead of overriding onStart, onPause, onResume, onStop - use Lifecycle*Effects for a more native compose cleanup. Requires a higher version of the lifecycle library.

PiperOrigin-RevId: 712542884

constants.gradle

@@ -46,7 +46,7 @@ project.ext {
     androidxConstraintLayoutVersion = '2.1.4'
     androidxCoreVersion = '1.8.0'
     androidxExifInterfaceVersion = '1.3.6'
-    androidxLifecycleVersion = '2.6.0'
+    androidxLifecycleVersion = '2.8.7'
     androidxMediaVersion = '1.7.0'
     androidxRecyclerViewVersion = '1.3.0'
     androidxMaterialVersion = '1.8.0'

demos/compose/build.gradle

@@ -74,6 +74,7 @@ dependencies {
     implementation 'androidx.compose.material3:material3'
     implementation 'androidx.compose.material:material-icons-extended'
     implementation 'androidx.compose.ui:ui-tooling-preview'
+    implementation 'androidx.lifecycle:lifecycle-runtime-compose:' + androidxLifecycleVersion
     implementation 'com.google.android.material:material:' + androidxMaterialVersion
 
     implementation project(modulePrefix + 'lib-exoplayer')

demos/compose/src/main/java/androidx/media3/demo/compose/MainActivity.kt

@@ -16,6 +16,7 @@
 package androidx.media3.demo.compose
 
 import android.content.Context
+import android.os.Build
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
@@ -34,6 +35,8 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.platform.LocalContext
+import androidx.lifecycle.compose.LifecycleResumeEffect
+import androidx.lifecycle.compose.LifecycleStartEffect
 import androidx.media3.common.MediaItem
 import androidx.media3.common.Player
 import androidx.media3.demo.compose.buttons.ExtraControls
@@ -57,7 +60,34 @@ class MainActivity : ComponentActivity() {
 fun ComposeDemoApp(modifier: Modifier = Modifier) {
   val context = LocalContext.current
   var player by remember { mutableStateOf<Player?>(null) }
-  player = initializePlayer(context)
+
+  // See the following resources
+  // https://developer.android.com/topic/libraries/architecture/lifecycle#onStop-and-savedState
+  // https://developer.android.com/develop/ui/views/layout/support-multi-window-mode#multi-window_mode_configuration
+  // https://developer.android.com/develop/ui/compose/layouts/adaptive/support-multi-window-mode#android_9
+
+  if (Build.VERSION.SDK_INT > 23) {
+    // Initialize/release in onStart()/onStop() only because in a multi-window environment multiple
+    // apps can be visible at the same time. The apps that are out-of-focus are paused, but video
+    // playback should continue.
+    LifecycleStartEffect(Unit) {
+      player = initializePlayer(context)
+      onStopOrDispose {
+        player?.apply { release() }
+        player = null
+      }
+    }
+  } else {
+    // Call to onStop() is not guaranteed, hence we release the Player in onPause() instead
+    LifecycleResumeEffect(Unit) {
+      player = initializePlayer(context)
+      onPauseOrDispose {
+        player?.apply { release() }
+        player = null
+      }
+    }
+  }
+
   player?.let { MediaPlayerScreen(player = it, modifier = modifier.fillMaxSize()) }
 }