Compat logic for MediaController.getCustomLayout

When a new media session sets media button preferences, we need to
"translate" them back to a custom layout to ensure the user preferences
are represented as closely as possible when the controller uses the
old button placement rules.

PiperOrigin-RevId: 693306153

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

@@ -410,6 +410,8 @@ public class MediaController implements Player {
      * Called when the {@linkplain #getCustomLayout() custom layout} changed.
      *
      * <p>This method will be deprecated, prefer to use {@link #onMediaButtonPreferencesChanged}.
+     * Note that the media button preferences use {@link CommandButton#slots} to define the allowed
+     * button placement.
      *
      * <p>The custom layout can change when either the session {@linkplain
      * MediaSession#setCustomLayout changes the custom layout}, or when the session {@linkplain
@@ -1116,6 +1118,8 @@ public class MediaController implements Player {
    * Returns the custom layout.
    *
    * <p>This method will be deprecated, prefer to use {@link #getMediaButtonPreferences()} instead.
+   * Note that the media button preferences use {@link CommandButton#slots} to define the allowed
+   * button placement.
    *
    * <p>After being connected, a change of the custom layout is reported with {@link
    * Listener#onCustomLayoutChanged(MediaController, List)}.
@@ -1127,7 +1131,8 @@ public class MediaController implements Player {
    */
   @UnstableApi
   public final ImmutableList<CommandButton> getCustomLayout() {
-    return getMediaButtonPreferences();
+    verifyApplicationThread();
+    return isConnected() ? impl.getCustomLayout() : ImmutableList.of();
   }
 
   /**
@@ -2208,6 +2213,8 @@ public class MediaController implements Player {
 
     ImmutableList<CommandButton> getMediaButtonPreferences();
 
+    ImmutableList<CommandButton> getCustomLayout();
+
     ImmutableList<CommandButton> getCommandButtonsForMediaItem(MediaItem mediaItem);
 
     Bundle getSessionExtras();

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

@@ -93,7 +93,6 @@ import com.google.common.util.concurrent.MoreExecutors;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
-import java.util.Objects;
 import java.util.concurrent.CancellationException;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeoutException;
@@ -128,6 +127,7 @@ import org.checkerframework.checker.nullness.qual.NonNull;
   private ImmutableList<CommandButton> customLayoutOriginal;
   private ImmutableList<CommandButton> mediaButtonPreferencesOriginal;
   private ImmutableList<CommandButton> resolvedMediaButtonPreferences;
+  private ImmutableList<CommandButton> resolvedCustomLayout;
   private ImmutableMap<String, CommandButton> commandButtonsForMediaItemsMap;
   private SessionCommands sessionCommands;
   private Commands playerCommandsFromSession;
@@ -158,6 +158,7 @@ import org.checkerframework.checker.nullness.qual.NonNull;
     customLayoutOriginal = ImmutableList.of();
     mediaButtonPreferencesOriginal = ImmutableList.of();
     resolvedMediaButtonPreferences = ImmutableList.of();
+    resolvedCustomLayout = ImmutableList.of();
     commandButtonsForMediaItemsMap = ImmutableMap.of();
     playerCommandsFromSession = Commands.EMPTY;
     playerCommandsFromPlayer = Commands.EMPTY;
@@ -751,6 +752,11 @@ import org.checkerframework.checker.nullness.qual.NonNull;
     return resolvedMediaButtonPreferences;
   }
 
+  @Override
+  public ImmutableList<CommandButton> getCustomLayout() {
+    return resolvedCustomLayout;
+  }
+
   @Override
   public ImmutableList<CommandButton> getCommandButtonsForMediaItem(MediaItem mediaItem) {
     ImmutableList<String> supportedActions = mediaItem.mediaMetadata.supportedCommands;
@@ -2662,6 +2668,9 @@ import org.checkerframework.checker.nullness.qual.NonNull;
             sessionCommands,
             intersectedPlayerCommands,
             result.sessionExtras);
+    resolvedCustomLayout =
+        resolveCustomLayout(
+            resolvedMediaButtonPreferences, result.sessionExtras, intersectedPlayerCommands);
     ImmutableMap.Builder<String, CommandButton> commandButtonsForMediaItems =
         new ImmutableMap.Builder<>();
     for (int i = 0; i < result.commandButtonsForMediaItems.size(); i++) {
@@ -2842,8 +2851,10 @@ import org.checkerframework.checker.nullness.qual.NonNull;
           !Util.areEqual(intersectedPlayerCommands, prevIntersectedPlayerCommands);
     }
     boolean mediaButtonPreferencesChanged = false;
+    boolean customLayoutChanged = false;
     if (sessionCommandsChanged || intersectedPlayerCommandsChanged) {
       ImmutableList<CommandButton> oldMediaButtonPreferences = resolvedMediaButtonPreferences;
+      ImmutableList<CommandButton> oldCustomLayout = resolvedCustomLayout;
       resolvedMediaButtonPreferences =
           resolveMediaButtonPreferences(
               mediaButtonPreferencesOriginal,
@@ -2851,8 +2862,12 @@ import org.checkerframework.checker.nullness.qual.NonNull;
               sessionCommands,
               intersectedPlayerCommands,
               sessionExtras);
+      resolvedCustomLayout =
+          resolveCustomLayout(
+              resolvedMediaButtonPreferences, sessionExtras, intersectedPlayerCommands);
       mediaButtonPreferencesChanged =
           !resolvedMediaButtonPreferences.equals(oldMediaButtonPreferences);
+      customLayoutChanged = !resolvedCustomLayout.equals(oldCustomLayout);
     }
     if (intersectedPlayerCommandsChanged) {
       listeners.sendEvent(
@@ -2865,14 +2880,17 @@ import org.checkerframework.checker.nullness.qual.NonNull;
               listener ->
                   listener.onAvailableSessionCommandsChanged(getInstance(), sessionCommands));
     }
+    if (customLayoutChanged) {
+      getInstance()
+          .notifyControllerListener(
+              listener -> listener.onCustomLayoutChanged(getInstance(), resolvedCustomLayout));
+    }
     if (mediaButtonPreferencesChanged) {
       getInstance()
           .notifyControllerListener(
-              listener -> {
+              listener ->
-                listener.onCustomLayoutChanged(getInstance(), resolvedMediaButtonPreferences);
+                  listener.onMediaButtonPreferencesChanged(
-                listener.onMediaButtonPreferencesChanged(
+                      getInstance(), resolvedMediaButtonPreferences));
-                    getInstance(), resolvedMediaButtonPreferences);
-              });
     }
   }
 
@@ -2891,8 +2909,10 @@ import org.checkerframework.checker.nullness.qual.NonNull;
     boolean intersectedPlayerCommandsChanged =
         !Util.areEqual(intersectedPlayerCommands, prevIntersectedPlayerCommands);
     boolean mediaButtonPreferencesChanged = false;
+    boolean customLayoutChanged = false;
     if (intersectedPlayerCommandsChanged) {
       ImmutableList<CommandButton> oldMediaButtonPreferences = resolvedMediaButtonPreferences;
+      ImmutableList<CommandButton> oldCustomLayout = resolvedCustomLayout;
       resolvedMediaButtonPreferences =
           resolveMediaButtonPreferences(
               mediaButtonPreferencesOriginal,
@@ -2900,20 +2920,27 @@ import org.checkerframework.checker.nullness.qual.NonNull;
               sessionCommands,
               intersectedPlayerCommands,
               sessionExtras);
+      resolvedCustomLayout =
+          resolveCustomLayout(
+              resolvedMediaButtonPreferences, sessionExtras, intersectedPlayerCommands);
       mediaButtonPreferencesChanged =
           !resolvedMediaButtonPreferences.equals(oldMediaButtonPreferences);
+      customLayoutChanged = !resolvedCustomLayout.equals(oldCustomLayout);
       listeners.sendEvent(
           /* eventFlag= */ Player.EVENT_AVAILABLE_COMMANDS_CHANGED,
           listener -> listener.onAvailableCommandsChanged(intersectedPlayerCommands));
     }
+    if (customLayoutChanged) {
+      getInstance()
+          .notifyControllerListener(
+              listener -> listener.onCustomLayoutChanged(getInstance(), resolvedCustomLayout));
+    }
     if (mediaButtonPreferencesChanged) {
       getInstance()
           .notifyControllerListener(
-              listener -> {
+              listener ->
-                listener.onCustomLayoutChanged(getInstance(), resolvedMediaButtonPreferences);
+                  listener.onMediaButtonPreferencesChanged(
-                listener.onMediaButtonPreferencesChanged(
+                      getInstance(), resolvedMediaButtonPreferences));
-                    getInstance(), resolvedMediaButtonPreferences);
-              });
     }
   }
 
@@ -2922,6 +2949,7 @@ import org.checkerframework.checker.nullness.qual.NonNull;
       return;
     }
     ImmutableList<CommandButton> oldMediaButtonPreferences = resolvedMediaButtonPreferences;
+    ImmutableList<CommandButton> oldCustomLayout = resolvedCustomLayout;
     customLayoutOriginal = ImmutableList.copyOf(layout);
     resolvedMediaButtonPreferences =
         resolveMediaButtonPreferences(
@@ -2930,17 +2958,23 @@ import org.checkerframework.checker.nullness.qual.NonNull;
             sessionCommands,
             intersectedPlayerCommands,
             sessionExtras);
+    resolvedCustomLayout =
+        resolveCustomLayout(
+            resolvedMediaButtonPreferences, sessionExtras, intersectedPlayerCommands);
     boolean mediaButtonPreferencesChanged =
-        !Objects.equals(resolvedMediaButtonPreferences, oldMediaButtonPreferences);
+        !resolvedMediaButtonPreferences.equals(oldMediaButtonPreferences);
+    boolean customLayoutChanged = !resolvedCustomLayout.equals(oldCustomLayout);
     getInstance()
         .notifyControllerListener(
             listener -> {
               ListenableFuture<SessionResult> future =
                   checkNotNull(
-                      listener.onSetCustomLayout(getInstance(), resolvedMediaButtonPreferences),
+                      listener.onSetCustomLayout(getInstance(), resolvedCustomLayout),
                       "MediaController.Listener#onSetCustomLayout() must not return null");
+              if (customLayoutChanged) {
+                listener.onCustomLayoutChanged(getInstance(), resolvedCustomLayout);
+              }
               if (mediaButtonPreferencesChanged) {
-                listener.onCustomLayoutChanged(getInstance(), resolvedMediaButtonPreferences);
                 listener.onMediaButtonPreferencesChanged(
                     getInstance(), resolvedMediaButtonPreferences);
               }
@@ -2953,6 +2987,7 @@ import org.checkerframework.checker.nullness.qual.NonNull;
       return;
     }
     ImmutableList<CommandButton> oldMediaButtonPreferences = resolvedMediaButtonPreferences;
+    ImmutableList<CommandButton> oldCustomLayout = resolvedCustomLayout;
     mediaButtonPreferencesOriginal = ImmutableList.copyOf(mediaButtonPreferences);
     resolvedMediaButtonPreferences =
         resolveMediaButtonPreferences(
@@ -2961,17 +2996,23 @@ import org.checkerframework.checker.nullness.qual.NonNull;
             sessionCommands,
             intersectedPlayerCommands,
             sessionExtras);
+    resolvedCustomLayout =
+        resolveCustomLayout(
+            resolvedMediaButtonPreferences, sessionExtras, intersectedPlayerCommands);
     boolean mediaButtonPreferencesChanged =
-        !Objects.equals(resolvedMediaButtonPreferences, oldMediaButtonPreferences);
+        !resolvedMediaButtonPreferences.equals(oldMediaButtonPreferences);
+    boolean customLayoutChanged = !resolvedCustomLayout.equals(oldCustomLayout);
     getInstance()
         .notifyControllerListener(
             listener -> {
               ListenableFuture<SessionResult> future =
                   checkNotNull(
-                      listener.onSetCustomLayout(getInstance(), resolvedMediaButtonPreferences),
+                      listener.onSetCustomLayout(getInstance(), resolvedCustomLayout),
                       "MediaController.Listener#onSetCustomLayout() must not return null");
+              if (customLayoutChanged) {
+                listener.onCustomLayoutChanged(getInstance(), resolvedCustomLayout);
+              }
               if (mediaButtonPreferencesChanged) {
-                listener.onCustomLayoutChanged(getInstance(), resolvedMediaButtonPreferences);
                 listener.onMediaButtonPreferencesChanged(
                     getInstance(), resolvedMediaButtonPreferences);
               }
@@ -2984,6 +3025,7 @@ import org.checkerframework.checker.nullness.qual.NonNull;
       return;
     }
     ImmutableList<CommandButton> oldMediaButtonPreferences = resolvedMediaButtonPreferences;
+    ImmutableList<CommandButton> oldCustomLayout = resolvedCustomLayout;
     sessionExtras = extras;
     resolvedMediaButtonPreferences =
         resolveMediaButtonPreferences(
@@ -2992,14 +3034,20 @@ import org.checkerframework.checker.nullness.qual.NonNull;
             sessionCommands,
             intersectedPlayerCommands,
             sessionExtras);
+    resolvedCustomLayout =
+        resolveCustomLayout(
+            resolvedMediaButtonPreferences, sessionExtras, intersectedPlayerCommands);
     boolean mediaButtonPreferencesChanged =
-        !Objects.equals(resolvedMediaButtonPreferences, oldMediaButtonPreferences);
+        !resolvedMediaButtonPreferences.equals(oldMediaButtonPreferences);
+    boolean customLayoutChanged = !resolvedCustomLayout.equals(oldCustomLayout);
     getInstance()
         .notifyControllerListener(
             listener -> {
               listener.onExtrasChanged(getInstance(), extras);
+              if (customLayoutChanged) {
+                listener.onCustomLayoutChanged(getInstance(), resolvedCustomLayout);
+              }
               if (mediaButtonPreferencesChanged) {
-                listener.onCustomLayoutChanged(getInstance(), resolvedMediaButtonPreferences);
                 listener.onMediaButtonPreferencesChanged(
                     getInstance(), resolvedMediaButtonPreferences);
               }
@@ -3365,6 +3413,22 @@ import org.checkerframework.checker.nullness.qual.NonNull;
         resolvedButtons, sessionCommands, playerCommands);
   }
 
+  private static ImmutableList<CommandButton> resolveCustomLayout(
+      List<CommandButton> mediaButtonPreferences,
+      Bundle sessionExtras,
+      Player.Commands availableCommands) {
+    boolean backSlotAllowed =
+        !sessionExtras.getBoolean(MediaConstants.EXTRAS_KEY_SLOT_RESERVATION_SEEK_TO_PREV)
+            && !availableCommands.containsAny(
+                Player.COMMAND_SEEK_TO_PREVIOUS_MEDIA_ITEM, Player.COMMAND_SEEK_TO_PREVIOUS);
+    boolean forwardSlotAllowed =
+        !sessionExtras.getBoolean(MediaConstants.EXTRAS_KEY_SLOT_RESERVATION_SEEK_TO_NEXT)
+            && !availableCommands.containsAny(
+                Player.COMMAND_SEEK_TO_NEXT_MEDIA_ITEM, Player.COMMAND_SEEK_TO_NEXT);
+    return CommandButton.getCustomLayoutFromMediaButtonPreferences(
+        mediaButtonPreferences, backSlotAllowed, forwardSlotAllowed);
+  }
+
   private static Commands createIntersectedCommandsEnsuringCommandReleaseAvailable(
       Commands commandFromSession, Commands commandsFromPlayer) {
     Commands intersectedCommands = MediaUtils.intersect(commandFromSession, commandsFromPlayer);

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

@@ -437,6 +437,11 @@ import org.checkerframework.checker.initialization.qual.UnderInitialization;
     return controllerInfo.mediaButtonPreferences;
   }
 
+  @Override
+  public ImmutableList<CommandButton> getCustomLayout() {
+    return controllerInfo.mediaButtonPreferences;
+  }
+
   @Override
   public Bundle getSessionExtras() {
     return controllerInfo.sessionExtras;

libraries/test_session_current/src/androidTest/java/androidx/media3/session/MediaSessionServiceTest.java

@@ -335,8 +335,7 @@ public class MediaSessionServiceTest {
         .containsExactly(
             button1
                 .copyWithIsEnabled(false)
-                .copyWithSlots(
+                .copyWithSlots(ImmutableIntArray.of(CommandButton.SLOT_FORWARD)),
-                    ImmutableIntArray.of(CommandButton.SLOT_FORWARD, CommandButton.SLOT_OVERFLOW)),
             button2
                 .copyWithIsEnabled(false)
                 .copyWithSlots(ImmutableIntArray.of(CommandButton.SLOT_OVERFLOW)))