1/* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16package android.car.cluster.demorenderer; 17 18import android.content.Context; 19import android.media.MediaMetadata; 20import android.media.session.MediaController; 21import android.media.session.MediaSessionManager; 22import android.media.session.MediaSessionManager.OnActiveSessionsChangedListener; 23import android.media.session.PlaybackState; 24import android.util.Log; 25 26import java.lang.ref.WeakReference; 27import java.util.List; 28 29/** 30 * Reports current media status to instrument cluster renderer. 31 */ 32public class MediaStateMonitor { 33 34 private final static String TAG = MediaStateMonitor.class.getSimpleName(); 35 36 private final Context mContext; 37 private final MediaListener mMediaListener; 38 private MediaController mPrimaryMediaController; 39 private OnActiveSessionsChangedListener mActiveSessionsChangedListener; 40 private MediaSessionManager mMediaSessionManager; 41 private MediaStateListener mListener; 42 43 public MediaStateMonitor(Context context, MediaStateListener listener) { 44 mListener = listener; 45 mContext = context; 46 mMediaListener = new MediaListener(this); 47 mActiveSessionsChangedListener = controllers -> onActiveSessionsChanged(controllers); 48 mMediaSessionManager = mContext.getSystemService(MediaSessionManager.class); 49 mMediaSessionManager.addOnActiveSessionsChangedListener( 50 mActiveSessionsChangedListener, null); 51 52 onActiveSessionsChanged(mMediaSessionManager.getActiveSessions(null)); 53 } 54 55 private void onActiveSessionsChanged(List<MediaController> controllers) { 56 Log.d(TAG, "onActiveSessionsChanged, controllers found: " + controllers.size()); 57 MediaController newPrimaryController = null; 58 if (controllers.size() > 0) { 59 newPrimaryController = controllers.get(0); 60 if (mPrimaryMediaController == newPrimaryController) { 61 // Primary media controller has not been changed. 62 return; 63 } 64 } 65 66 releasePrimaryMediaController(); 67 68 if (newPrimaryController != null) { 69 mPrimaryMediaController = newPrimaryController; 70 mPrimaryMediaController.registerCallback(mMediaListener); 71 } 72 updateRendererMediaStatusIfAvailable(); 73 74 for (MediaController m : controllers) { 75 Log.d(TAG, m + ": " + m.getPackageName()); 76 } 77 } 78 79 public void release() { 80 releasePrimaryMediaController(); 81 if (mActiveSessionsChangedListener != null) { 82 mMediaSessionManager.removeOnActiveSessionsChangedListener( 83 mActiveSessionsChangedListener); 84 mActiveSessionsChangedListener = null; 85 } 86 mMediaSessionManager = null; 87 } 88 89 private void releasePrimaryMediaController() { 90 if (mPrimaryMediaController != null) { 91 mPrimaryMediaController.unregisterCallback(mMediaListener); 92 mPrimaryMediaController = null; 93 } 94 } 95 96 private void updateRendererMediaStatusIfAvailable() { 97 mListener.onMetadataChanged( 98 mPrimaryMediaController == null ? null : mPrimaryMediaController.getMetadata()); 99 mListener.onPlaybackStateChanged( 100 mPrimaryMediaController == null 101 ? null : mPrimaryMediaController.getPlaybackState()); 102 } 103 104 private void onPlaybackStateChanged(PlaybackState state) { 105 mListener.onPlaybackStateChanged(state); 106 } 107 108 private void onMetadataChanged(MediaMetadata metadata) { 109 mListener.onMetadataChanged(metadata); 110 } 111 112 public interface MediaStateListener { 113 void onPlaybackStateChanged(PlaybackState playbackState); 114 void onMetadataChanged(MediaMetadata metadata); 115 } 116 117 118 private static class MediaListener extends MediaController.Callback { 119 private final WeakReference<MediaStateMonitor> mServiceRef; 120 121 MediaListener(MediaStateMonitor service) { 122 mServiceRef = new WeakReference<>(service); 123 } 124 125 @Override 126 public void onPlaybackStateChanged(PlaybackState state) { 127 MediaStateMonitor service = mServiceRef.get(); 128 if (service != null) { 129 service.onPlaybackStateChanged(state); 130 } 131 } 132 133 @Override 134 public void onMetadataChanged(MediaMetadata metadata) { 135 MediaStateMonitor service = mServiceRef.get(); 136 if (service != null) { 137 service.onMetadataChanged(metadata); 138 } 139 } 140 } 141} 142