Add action to startSelfIntent to easily distinguish it as app

I was debugging start commands I shouldn't be recieving, and the
startSelfIntent with empty action was sort of confusing because
it wasn't immediately obvious where it came from. Adding a unique
action string doesn't have any ill effects and allows easily
identifying these intents in onStartCommand().

Author: nift4

libraries/session/src/main/java/androidx/media3/session/DefaultActionFactory.java

@@ -48,7 +48,6 @@
 /** The default {@link MediaNotification.ActionFactory}. */
 /* package */ final class DefaultActionFactory implements MediaNotification.ActionFactory {
 
-  private static final String ACTION_CUSTOM = "androidx.media3.session.CUSTOM_NOTIFICATION_ACTION";
   private static final String EXTRAS_KEY_ACTION_CUSTOM =
       "androidx.media3.session.EXTRAS_KEY_CUSTOM_NOTIFICATION_ACTION";
   public static final String EXTRAS_KEY_ACTION_CUSTOM_EXTRAS =
@@ -162,7 +161,7 @@ private int toKeyCode(@Player.Command long action) {
   @SuppressWarnings("PendingIntentMutability") // We can't use SaferPendingIntent
   private PendingIntent createCustomActionPendingIntent(
       MediaSession mediaSession, String action, Bundle extras) {
-    Intent intent = new Intent(ACTION_CUSTOM);
+    Intent intent = new Intent(MediaSessionService.ACTION_CUSTOM_NOTIFICATION_ACTION);
     intent.setData(mediaSession.getImpl().getUri());
     intent.setComponent(new ComponentName(service, service.getClass()));
     intent.putExtra(EXTRAS_KEY_ACTION_CUSTOM, action);
@@ -182,7 +181,7 @@ public boolean isMediaAction(Intent intent) {
 
   /** Returns whether {@code intent} was part of a {@link #createCustomAction custom action }. */
   public boolean isCustomAction(Intent intent) {
-    return ACTION_CUSTOM.equals(intent.getAction());
+    return MediaSessionService.ACTION_CUSTOM_NOTIFICATION_ACTION.equals(intent.getAction());
   }
 
   /**

libraries/session/src/main/java/androidx/media3/session/MediaNotificationManager.java

@@ -91,6 +91,7 @@ public MediaNotificationManager(
     mainHandler = Util.createHandler(Looper.getMainLooper(), /* callback= */ this);
     mainExecutor = (runnable) -> Util.postOrRun(mainHandler, runnable);
     startSelfIntent = new Intent(mediaSessionService, mediaSessionService.getClass());
+    startSelfIntent.setAction(MediaSessionService.ACTION_START_SELF);
     controllerMap = new HashMap<>();
     startedInForeground = false;
     isUserEngagedTimeoutEnabled = true;

libraries/session/src/main/java/androidx/media3/session/MediaSessionService.java

@@ -166,6 +166,39 @@ default void onForegroundServiceStartNotAllowedException() {}
   /** The action for {@link Intent} filter that must be declared by the service. */
   public static final String SERVICE_INTERFACE = "androidx.media3.session.MediaSessionService";
 
+  /**
+   * The action of an {@link Intent} sent to this service by itself when it is already running, but
+   * wishes to move into the foreground state.
+   *
+   * <p>This action is not intended for starting the service from anywhere except custom foreground
+   * service handling. Most apps will never need to send this action themselves.
+   *
+   * <p>If an {@link Intent} with this action is received in a subclass' {@link
+   * #onStartCommand(Intent, int, int)} method, the intent should be passed to the superclass
+   * (MediaSessionService) implementation. No further action is required to handle it.
+   */
+  @UnstableApi
+  public static final String ACTION_START_SELF =
+      "androidx.media3.session.MediaSessionService.ACTION_START_SELF";
+
+  /**
+   * The action of an {@link Intent} sent to this service by the system when a custom notification
+   * or session action was clicked.
+   *
+   * <p>If an {@link Intent} with this action is received in a subclass' {@link
+   * #onStartCommand(Intent, int, int)} method, the intent should be passed to the superclass
+   * (MediaSessionService) implementation.
+   *
+   * <p>This {@link Intent} is not intended to be intercepted by subclasses. If subclasses wish to
+   * handle custom notification actions, {@link
+   * MediaNotification.Provider#handleCustomCommand(MediaSession, String, Bundle)} or {@link
+   * MediaSession.Callback#onCustomCommand(MediaSession, ControllerInfo, SessionCommand, Bundle)}
+   * are appropriate.
+   */
+  @UnstableApi
+  public static final String ACTION_CUSTOM_NOTIFICATION_ACTION =
+      "androidx.media3.session.CUSTOM_NOTIFICATION_ACTION";
+
   /**
    * The default timeout for a session to stay in a foreground service state after it paused,
    * stopped, failed or ended.
@@ -439,9 +472,18 @@ public IBinder onBind(@Nullable Intent intent) {
   /**
    * Called when a component calls {@link android.content.Context#startService(Intent)}.
    *
-   * <p>The default implementation handles the incoming media button events. In this case, the
-   * intent will have the action {@link Intent#ACTION_MEDIA_BUTTON}. Override this method if this
-   * service also needs to handle actions other than {@link Intent#ACTION_MEDIA_BUTTON}.
+   * <p>The default implementation handles the following events:
+   *
+   * <ul>
+   *   <li>incoming media button events with the {@link Intent} action {@link
+   *       Intent#ACTION_MEDIA_BUTTON}.
+   *   <li>custom notification actions with {@link Intent} action {@link
+   *       #ACTION_CUSTOM_NOTIFICATION_ACTION}
+   *   <li>foreground service state changes with {@link Intent} action {@link #ACTION_START_SELF}
+   * </ul>
+   *
+   * <p>Override this method if this service also needs to handle actions other than those mentioned
+   * above.
    *
    * <p>This method will be called on the main thread.
    */