1 /* 2 * Copyright (C) 2017 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 */ 16 17 package com.googlecode.android_scripting.facade.bluetooth.media; 18 19 import android.media.browse.MediaBrowser.MediaItem; 20 import android.media.session.*; 21 import android.os.Bundle; 22 import android.service.media.MediaBrowserService; 23 24 import com.googlecode.android_scripting.facade.bluetooth.BluetoothMediaFacade; 25 import com.googlecode.android_scripting.Log; 26 27 import java.util.ArrayList; 28 import java.util.List; 29 30 /** 31 * A {@link MediaBrowserService} implemented in the SL4A App to intercept Media keys and 32 * commands. 33 * This would be running on the Phone (AVRCP TG device) and whenever the device receives a media 34 * command from Car (a AVRCP CT), this MediaBrowserService's MediaSession would intercept it. 35 * Helps to verify the commands received by the Phone (AVRCP TG) are the same as what was sent from 36 * Car (AVRCP CT). 37 */ 38 public class BluetoothSL4AAudioSrcMBS extends MediaBrowserService { 39 private static final String TAG = "BluetoothSL4AAudioSrcMBS"; 40 private static final String MEDIA_ROOT_ID = "__ROOT__"; 41 42 private MediaSession mMediaSession = null; 43 private MediaSession.Token mSessionToken = null; 44 private BluetoothMediaPlayback mPlayback = null; 45 private static BluetoothSL4AAudioSrcMBS sAvrcpMediaBrowserService; 46 private static final String CMD_MEDIA_PLAY = "play"; 47 private static final String CMD_MEDIA_PAUSE = "pause"; 48 private static final String CMD_MEDIA_SKIP_NEXT = "skipNext"; 49 private static final String CMD_MEDIA_SKIP_PREV = "skipPrev"; 50 51 /** 52 * MediaSession callback dispatching the corresponding <code>PlaybackState</code> to 53 * {@link BluetoothMediaFacade} 54 */ 55 private MediaSession.Callback mMediaSessionCallback = 56 new MediaSession.Callback() { 57 @Override 58 public void onPlay() { 59 Log.d(TAG + " onPlay"); 60 mPlayback.play(); 61 } 62 63 @Override 64 public void onPause() { 65 Log.d(TAG + " onPause"); 66 mPlayback.pause(); 67 } 68 69 @Override 70 public void onRewind() { 71 Log.d(TAG + " onRewind"); 72 } 73 74 @Override 75 public void onFastForward() { 76 Log.d(TAG + " onFastForward"); 77 } 78 79 @Override 80 public void onSkipToNext() { 81 Log.d(TAG + " onSkipToNext"); 82 mPlayback.skipNext(); 83 } 84 85 @Override 86 public void onSkipToPrevious() { 87 Log.d(TAG + " onSkipToPrevious"); 88 mPlayback.skipPrev(); 89 } 90 91 @Override 92 public void onStop() { 93 Log.d(TAG + " onStop"); 94 mPlayback.stop(); 95 } 96 }; 97 98 /** 99 * Returns the currently set instance of {@link BluetoothSL4AAudioSrcMBS} 100 * 101 * @return current instance of {@link BluetoothSL4AAudioSrcMBS} 102 */ getAvrcpMediaBrowserService()103 public static synchronized BluetoothSL4AAudioSrcMBS getAvrcpMediaBrowserService() { 104 return sAvrcpMediaBrowserService; 105 } 106 107 /** 108 * Handle a Media Playback Command. 109 * Pass it to the appropriate {@link BluetoothMediaPlayback} method 110 * 111 * @param command - command to handle 112 */ handleMediaCommand(String command)113 public void handleMediaCommand(String command) { 114 if (mPlayback == null) { 115 Log.d(TAG + " handleMediaCommand Failed since Playback is null"); 116 return; 117 } 118 switch (command) { 119 case CMD_MEDIA_PLAY: 120 mPlayback.play(); 121 break; 122 case CMD_MEDIA_PAUSE: 123 mPlayback.pause(); 124 break; 125 case CMD_MEDIA_SKIP_NEXT: 126 mPlayback.skipNext(); 127 break; 128 case CMD_MEDIA_SKIP_PREV: 129 mPlayback.skipPrev(); 130 break; 131 default: 132 Log.d(TAG + " Unknown command " + command); 133 } 134 return; 135 } 136 137 /** 138 * We do the following on the BluetoothSL4AAudioSrcMBS onCreate(): 139 * 1. Create a new MediaSession 140 * 2. Register a callback with the created MediaSession 141 * 3. Set its playback state and set the session to active. 142 * 4. Create a new BluetoothMediaPlayback instance to handle all the "music playing" 143 * 5. Set the created MediaSession active 144 */ 145 @Override onCreate()146 public void onCreate() { 147 Log.d(TAG + " onCreate"); 148 super.onCreate(); 149 sAvrcpMediaBrowserService = this; 150 mMediaSession = new MediaSession(this, TAG); 151 mSessionToken = mMediaSession.getSessionToken(); 152 setSessionToken(mSessionToken); 153 mMediaSession.setCallback(mMediaSessionCallback); 154 mMediaSession.setFlags(MediaSession.FLAG_HANDLES_MEDIA_BUTTONS 155 | MediaSession.FLAG_HANDLES_TRANSPORT_CONTROLS); 156 // Note - MediaButton Intent is not received until the session has a PlaybackState 157 // whose state is set to something other than STATE_STOPPED or STATE_NONE 158 mPlayback = new BluetoothMediaPlayback(); 159 if (mPlayback == null) { 160 Log.e(TAG + "Playback alloc error"); 161 } 162 mPlayback.setMediaSession(mMediaSession); 163 PlaybackState state = new PlaybackState.Builder() 164 .setActions(PlaybackState.ACTION_PLAY | PlaybackState.ACTION_PAUSE 165 | PlaybackState.ACTION_SKIP_TO_NEXT | PlaybackState.ACTION_SKIP_TO_PREVIOUS 166 | PlaybackState.ACTION_STOP) 167 .setState(PlaybackState.STATE_PLAYING, PlaybackState.PLAYBACK_POSITION_UNKNOWN, 1) 168 .build(); 169 mMediaSession.setPlaybackState(state); 170 mMediaSession.setActive(true); 171 172 // Sets the PlaybackState to STOPPED now that we are able to receive MediaSession callbacks. 173 state = new PlaybackState.Builder() 174 .setActions(PlaybackState.ACTION_PLAY | PlaybackState.ACTION_PAUSE 175 | PlaybackState.ACTION_SKIP_TO_NEXT | PlaybackState.ACTION_SKIP_TO_PREVIOUS 176 | PlaybackState.ACTION_STOP) 177 .setState(PlaybackState.STATE_STOPPED, PlaybackState.PLAYBACK_POSITION_UNKNOWN, 1) 178 .build(); 179 mMediaSession.setPlaybackState(state); 180 } 181 182 @Override onDestroy()183 public void onDestroy() { 184 Log.d(TAG + " onDestroy"); 185 mPlayback.releaseMediaPlayer(); 186 mMediaSession.release(); 187 mMediaSession = null; 188 mSessionToken = null; 189 sAvrcpMediaBrowserService = null; 190 super.onDestroy(); 191 } 192 193 @Override onGetRoot(String clientPackageName, int clientUid, Bundle rootHints)194 public BrowserRoot onGetRoot(String clientPackageName, int clientUid, Bundle rootHints) { 195 BrowserRoot mediaRoot = new BrowserRoot(MEDIA_ROOT_ID, null); 196 return mediaRoot; 197 } 198 199 @Override onLoadChildren(String parentId, Result<List<MediaItem>> result)200 public void onLoadChildren(String parentId, Result<List<MediaItem>> result) { 201 List<MediaItem> mediaList = new ArrayList<MediaItem>(); 202 result.sendResult(mediaList); 203 } 204 205 /** 206 * Returns the TAG string 207 * 208 * @return <code>BluetoothSL4AAudioSrcMBS</code>'s tag 209 */ getTag()210 public static String getTag() { 211 return TAG; 212 } 213 } 214 215 216