Merge "Tweak the behavior of the MediaSessionStack" into lmp-mr1-dev

services/core/java/com/android/server/media/MediaSessionService.java

@@ -443,7 +443,7 @@ public class MediaSessionService extends SystemService implements Monitor {
         synchronized (mLock) {
             List<MediaSessionRecord> records = mPriorityStack.getActiveSessions(userId);
             int size = records.size();
-            if (size > 0) {
+            if (size > 0 && records.get(0).isPlaybackActive(false)) {
                 rememberMediaButtonReceiverLocked(records.get(0));
             }
             ArrayList<MediaSession.Token> tokens = new ArrayList<MediaSession.Token>();
@@ -702,8 +702,12 @@ public class MediaSessionService extends SystemService implements Monitor {
 
             try {
                 synchronized (mLock) {
+                    // If we don't have a media button receiver to fall back on
+                    // include non-playing sessions for dispatching
+                    boolean useNotPlayingSessions = mUserRecords.get(
+                            ActivityManager.getCurrentUser()).mLastMediaButtonReceiver == null;
                     MediaSessionRecord session = mPriorityStack
-                            .getDefaultMediaButtonSession(mCurrentUserId);
+                            .getDefaultMediaButtonSession(mCurrentUserId, useNotPlayingSessions);
                     if (isVoiceKey(keyEvent.getKeyCode())) {
                         handleVoiceKeyEventLocked(keyEvent, needWakeLock, session);
                     } else {

services/core/java/com/android/server/media/MediaSessionStack.java

@@ -51,6 +51,9 @@ public class MediaSessionStack {
 
     private MediaSessionRecord mGlobalPrioritySession;
 
+    // The last record that either entered one of the playing states or was
+    // added.
+    private MediaSessionRecord mLastInterestingRecord;
     private MediaSessionRecord mCachedButtonReceiver;
     private MediaSessionRecord mCachedDefault;
     private MediaSessionRecord mCachedVolumeDefault;
@@ -65,6 +68,7 @@ public class MediaSessionStack {
     public void addSession(MediaSessionRecord record) {
         mSessions.add(record);
         clearCache();
+        mLastInterestingRecord = record;
     }
 
     /**
@@ -93,6 +97,9 @@ public class MediaSessionStack {
             mSessions.remove(record);
             mSessions.add(0, record);
             clearCache();
+            // This becomes the last interesting record since it entered a
+            // playing state
+            mLastInterestingRecord = record;
             return true;
         } else if (!MediaSession.isActiveState(newState)) {
             // Just clear the volume cache when a state goes inactive
@@ -168,9 +175,11 @@ public class MediaSessionStack {
      * Get the highest priority session that can handle media buttons.
      *
      * @param userId The user to check.
+     * @param includeNotPlaying Return a non-playing session if nothing else is
+     *            available
      * @return The default media button session or null.
      */
-    public MediaSessionRecord getDefaultMediaButtonSession(int userId) {
+    public MediaSessionRecord getDefaultMediaButtonSession(int userId, boolean includeNotPlaying) {
         if (mGlobalPrioritySession != null && mGlobalPrioritySession.isActive()) {
             return mGlobalPrioritySession;
         }
@@ -180,7 +189,25 @@ public class MediaSessionStack {
         ArrayList<MediaSessionRecord> records = getPriorityListLocked(true,
                 MediaSession.FLAG_HANDLES_MEDIA_BUTTONS, userId);
         if (records.size() > 0) {
-            mCachedButtonReceiver = records.get(0);
+            MediaSessionRecord record = records.get(0);
+            if (record.isPlaybackActive(false)) {
+                // Since we're going to send a button event to this record make
+                // it the last interesting one.
+                mLastInterestingRecord = record;
+                mCachedButtonReceiver = record;
+            } else if (mLastInterestingRecord != null) {
+                if (records.contains(mLastInterestingRecord)) {
+                    mCachedButtonReceiver = mLastInterestingRecord;
+                } else {
+                    // That record is no longer used. Clear its reference.
+                    mLastInterestingRecord = null;
+                }
+            }
+            if (includeNotPlaying && mCachedButtonReceiver == null) {
+                // If we really want a record and we didn't find one yet use the
+                // highest priority session even if it's not playing.
+                mCachedButtonReceiver = record;
+            }
         }
         return mCachedButtonReceiver;
     }