1 /* 2 * Copyright (C) 2014 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 android.media.session; 18 19 import android.annotation.IntDef; 20 import android.annotation.NonNull; 21 import android.annotation.Nullable; 22 import android.app.Activity; 23 import android.app.PendingIntent; 24 import android.content.Context; 25 import android.content.Intent; 26 import android.content.pm.ParceledListSlice; 27 import android.media.AudioAttributes; 28 import android.media.MediaDescription; 29 import android.media.MediaMetadata; 30 import android.media.Rating; 31 import android.media.VolumeProvider; 32 import android.net.Uri; 33 import android.os.Bundle; 34 import android.os.Handler; 35 import android.os.Looper; 36 import android.os.Message; 37 import android.os.Parcel; 38 import android.os.Parcelable; 39 import android.os.RemoteException; 40 import android.os.ResultReceiver; 41 import android.os.UserHandle; 42 import android.service.media.MediaBrowserService; 43 import android.text.TextUtils; 44 import android.util.Log; 45 import android.view.KeyEvent; 46 47 import java.lang.annotation.Retention; 48 import java.lang.annotation.RetentionPolicy; 49 import java.lang.ref.WeakReference; 50 import java.util.List; 51 52 /** 53 * Allows interaction with media controllers, volume keys, media buttons, and 54 * transport controls. 55 * <p> 56 * A MediaSession should be created when an app wants to publish media playback 57 * information or handle media keys. In general an app only needs one session 58 * for all playback, though multiple sessions can be created to provide finer 59 * grain controls of media. 60 * <p> 61 * Once a session is created the owner of the session may pass its 62 * {@link #getSessionToken() session token} to other processes to allow them to 63 * create a {@link MediaController} to interact with the session. 64 * <p> 65 * To receive commands, media keys, and other events a {@link Callback} must be 66 * set with {@link #setCallback(Callback)} and {@link #setActive(boolean) 67 * setActive(true)} must be called. 68 * <p> 69 * When an app is finished performing playback it must call {@link #release()} 70 * to clean up the session and notify any controllers. 71 * <p> 72 * MediaSession objects are thread safe. 73 */ 74 public final class MediaSession { 75 private static final String TAG = "MediaSession"; 76 77 /** 78 * Set this flag on the session to indicate that it can handle media button 79 * events. 80 */ 81 public static final int FLAG_HANDLES_MEDIA_BUTTONS = 1 << 0; 82 83 /** 84 * Set this flag on the session to indicate that it handles transport 85 * control commands through its {@link Callback}. 86 */ 87 public static final int FLAG_HANDLES_TRANSPORT_CONTROLS = 1 << 1; 88 89 /** 90 * System only flag for a session that needs to have priority over all other 91 * sessions. This flag ensures this session will receive media button events 92 * regardless of the current ordering in the system. 93 * 94 * @hide 95 */ 96 public static final int FLAG_EXCLUSIVE_GLOBAL_PRIORITY = 1 << 16; 97 98 /** @hide */ 99 @Retention(RetentionPolicy.SOURCE) 100 @IntDef(flag = true, value = { 101 FLAG_HANDLES_MEDIA_BUTTONS, 102 FLAG_HANDLES_TRANSPORT_CONTROLS, 103 FLAG_EXCLUSIVE_GLOBAL_PRIORITY }) 104 public @interface SessionFlags { } 105 106 private final Object mLock = new Object(); 107 private final int mMaxBitmapSize; 108 109 private final MediaSession.Token mSessionToken; 110 private final MediaController mController; 111 private final ISession mBinder; 112 private final CallbackStub mCbStub; 113 114 private CallbackMessageHandler mCallback; 115 private VolumeProvider mVolumeProvider; 116 private PlaybackState mPlaybackState; 117 118 private boolean mActive = false; 119 120 /** 121 * Creates a new session. The session will automatically be registered with 122 * the system but will not be published until {@link #setActive(boolean) 123 * setActive(true)} is called. You must call {@link #release()} when 124 * finished with the session. 125 * 126 * @param context The context to use to create the session. 127 * @param tag A short name for debugging purposes. 128 */ 129 public MediaSession(@NonNull Context context, @NonNull String tag) { 130 this(context, tag, UserHandle.myUserId()); 131 } 132 133 /** 134 * Creates a new session as the specified user. To create a session as a 135 * user other than your own you must hold the 136 * {@link android.Manifest.permission#INTERACT_ACROSS_USERS_FULL} 137 * permission. 138 * 139 * @param context The context to use to create the session. 140 * @param tag A short name for debugging purposes. 141 * @param userId The user id to create the session as. 142 * @hide 143 */ 144 public MediaSession(@NonNull Context context, @NonNull String tag, int userId) { 145 if (context == null) { 146 throw new IllegalArgumentException("context cannot be null."); 147 } 148 if (TextUtils.isEmpty(tag)) { 149 throw new IllegalArgumentException("tag cannot be null or empty"); 150 } 151 mMaxBitmapSize = context.getResources().getDimensionPixelSize( 152 com.android.internal.R.dimen.config_mediaMetadataBitmapMaxSize); 153 mCbStub = new CallbackStub(this); 154 MediaSessionManager manager = (MediaSessionManager) context 155 .getSystemService(Context.MEDIA_SESSION_SERVICE); 156 try { 157 mBinder = manager.createSession(mCbStub, tag, userId); 158 mSessionToken = new Token(mBinder.getController()); 159 mController = new MediaController(context, mSessionToken); 160 } catch (RemoteException e) { 161 throw new RuntimeException("Remote error creating session.", e); 162 } 163 } 164 165 /** 166 * Set the callback to receive updates for the MediaSession. This includes 167 * media button events and transport controls. The caller's thread will be 168 * used to post updates. 169 * <p> 170 * Set the callback to null to stop receiving updates. 171 * 172 * @param callback The callback object 173 */ 174 public void setCallback(@Nullable Callback callback) { 175 setCallback(callback, null); 176 } 177 178 /** 179 * Set the callback to receive updates for the MediaSession. This includes 180 * media button events and transport controls. 181 * <p> 182 * Set the callback to null to stop receiving updates. 183 * 184 * @param callback The callback to receive updates on. 185 * @param handler The handler that events should be posted on. 186 */ 187 public void setCallback(@Nullable Callback callback, @Nullable Handler handler) { 188 synchronized (mLock) { 189 if (callback == null) { 190 if (mCallback != null) { 191 mCallback.mCallback.mSession = null; 192 } 193 mCallback = null; 194 return; 195 } 196 if (mCallback != null) { 197 // We're updating the callback, clear the session from the old 198 // one. 199 mCallback.mCallback.mSession = null; 200 } 201 if (handler == null) { 202 handler = new Handler(); 203 } 204 callback.mSession = this; 205 CallbackMessageHandler msgHandler = new CallbackMessageHandler(handler.getLooper(), 206 callback); 207 mCallback = msgHandler; 208 } 209 } 210 211 /** 212 * Set an intent for launching UI for this Session. This can be used as a 213 * quick link to an ongoing media screen. The intent should be for an 214 * activity that may be started using {@link Activity#startActivity(Intent)}. 215 * 216 * @param pi The intent to launch to show UI for this Session. 217 */ 218 public void setSessionActivity(@Nullable PendingIntent pi) { 219 try { 220 mBinder.setLaunchPendingIntent(pi); 221 } catch (RemoteException e) { 222 Log.wtf(TAG, "Failure in setLaunchPendingIntent.", e); 223 } 224 } 225 226 /** 227 * Set a pending intent for your media button receiver to allow restarting 228 * playback after the session has been stopped. If your app is started in 229 * this way an {@link Intent#ACTION_MEDIA_BUTTON} intent will be sent via 230 * the pending intent. 231 * 232 * @param mbr The {@link PendingIntent} to send the media button event to. 233 */ 234 public void setMediaButtonReceiver(@Nullable PendingIntent mbr) { 235 try { 236 mBinder.setMediaButtonReceiver(mbr); 237 } catch (RemoteException e) { 238 Log.wtf(TAG, "Failure in setMediaButtonReceiver.", e); 239 } 240 } 241 242 /** 243 * Set any flags for the session. 244 * 245 * @param flags The flags to set for this session. 246 */ 247 public void setFlags(@SessionFlags int flags) { 248 try { 249 mBinder.setFlags(flags); 250 } catch (RemoteException e) { 251 Log.wtf(TAG, "Failure in setFlags.", e); 252 } 253 } 254 255 /** 256 * Set the attributes for this session's audio. This will affect the 257 * system's volume handling for this session. If 258 * {@link #setPlaybackToRemote} was previously called it will stop receiving 259 * volume commands and the system will begin sending volume changes to the 260 * appropriate stream. 261 * <p> 262 * By default sessions use attributes for media. 263 * 264 * @param attributes The {@link AudioAttributes} for this session's audio. 265 */ 266 public void setPlaybackToLocal(AudioAttributes attributes) { 267 if (attributes == null) { 268 throw new IllegalArgumentException("Attributes cannot be null for local playback."); 269 } 270 try { 271 mBinder.setPlaybackToLocal(attributes); 272 } catch (RemoteException e) { 273 Log.wtf(TAG, "Failure in setPlaybackToLocal.", e); 274 } 275 } 276 277 /** 278 * Configure this session to use remote volume handling. This must be called 279 * to receive volume button events, otherwise the system will adjust the 280 * appropriate stream volume for this session. If 281 * {@link #setPlaybackToLocal} was previously called the system will stop 282 * handling volume changes for this session and pass them to the volume 283 * provider instead. 284 * 285 * @param volumeProvider The provider that will handle volume changes. May 286 * not be null. 287 */ 288 public void setPlaybackToRemote(@NonNull VolumeProvider volumeProvider) { 289 if (volumeProvider == null) { 290 throw new IllegalArgumentException("volumeProvider may not be null!"); 291 } 292 synchronized (mLock) { 293 mVolumeProvider = volumeProvider; 294 } 295 volumeProvider.setCallback(new VolumeProvider.Callback() { 296 @Override 297 public void onVolumeChanged(VolumeProvider volumeProvider) { 298 notifyRemoteVolumeChanged(volumeProvider); 299 } 300 }); 301 302 try { 303 mBinder.setPlaybackToRemote(volumeProvider.getVolumeControl(), 304 volumeProvider.getMaxVolume()); 305 mBinder.setCurrentVolume(volumeProvider.getCurrentVolume()); 306 } catch (RemoteException e) { 307 Log.wtf(TAG, "Failure in setPlaybackToRemote.", e); 308 } 309 } 310 311 /** 312 * Set if this session is currently active and ready to receive commands. If 313 * set to false your session's controller may not be discoverable. You must 314 * set the session to active before it can start receiving media button 315 * events or transport commands. 316 * 317 * @param active Whether this session is active or not. 318 */ 319 public void setActive(boolean active) { 320 if (mActive == active) { 321 return; 322 } 323 try { 324 mBinder.setActive(active); 325 mActive = active; 326 } catch (RemoteException e) { 327 Log.wtf(TAG, "Failure in setActive.", e); 328 } 329 } 330 331 /** 332 * Get the current active state of this session. 333 * 334 * @return True if the session is active, false otherwise. 335 */ 336 public boolean isActive() { 337 return mActive; 338 } 339 340 /** 341 * Send a proprietary event to all MediaControllers listening to this 342 * Session. It's up to the Controller/Session owner to determine the meaning 343 * of any events. 344 * 345 * @param event The name of the event to send 346 * @param extras Any extras included with the event 347 */ 348 public void sendSessionEvent(@NonNull String event, @Nullable Bundle extras) { 349 if (TextUtils.isEmpty(event)) { 350 throw new IllegalArgumentException("event cannot be null or empty"); 351 } 352 try { 353 mBinder.sendEvent(event, extras); 354 } catch (RemoteException e) { 355 Log.wtf(TAG, "Error sending event", e); 356 } 357 } 358 359 /** 360 * This must be called when an app has finished performing playback. If 361 * playback is expected to start again shortly the session can be left open, 362 * but it must be released if your activity or service is being destroyed. 363 */ 364 public void release() { 365 try { 366 mBinder.destroy(); 367 } catch (RemoteException e) { 368 Log.wtf(TAG, "Error releasing session: ", e); 369 } 370 } 371 372 /** 373 * Retrieve a token object that can be used by apps to create a 374 * {@link MediaController} for interacting with this session. The owner of 375 * the session is responsible for deciding how to distribute these tokens. 376 * 377 * @return A token that can be used to create a MediaController for this 378 * session 379 */ 380 public @NonNull Token getSessionToken() { 381 return mSessionToken; 382 } 383 384 /** 385 * Get a controller for this session. This is a convenience method to avoid 386 * having to cache your own controller in process. 387 * 388 * @return A controller for this session. 389 */ 390 public @NonNull MediaController getController() { 391 return mController; 392 } 393 394 /** 395 * Update the current playback state. 396 * 397 * @param state The current state of playback 398 */ 399 public void setPlaybackState(@Nullable PlaybackState state) { 400 mPlaybackState = state; 401 try { 402 mBinder.setPlaybackState(state); 403 } catch (RemoteException e) { 404 Log.wtf(TAG, "Dead object in setPlaybackState.", e); 405 } 406 } 407 408 /** 409 * Update the current metadata. New metadata can be created using 410 * {@link android.media.MediaMetadata.Builder}. 411 * 412 * @param metadata The new metadata 413 */ 414 public void setMetadata(@Nullable MediaMetadata metadata) { 415 if (metadata != null ) { 416 metadata = (new MediaMetadata.Builder(metadata, mMaxBitmapSize)).build(); 417 } 418 try { 419 mBinder.setMetadata(metadata); 420 } catch (RemoteException e) { 421 Log.wtf(TAG, "Dead object in setPlaybackState.", e); 422 } 423 } 424 425 /** 426 * Update the list of items in the play queue. It is an ordered list and 427 * should contain the current item, and previous or upcoming items if they 428 * exist. Specify null if there is no current play queue. 429 * <p> 430 * The queue should be of reasonable size. If the play queue is unbounded 431 * within your app, it is better to send a reasonable amount in a sliding 432 * window instead. 433 * 434 * @param queue A list of items in the play queue. 435 */ 436 public void setQueue(@Nullable List<QueueItem> queue) { 437 try { 438 mBinder.setQueue(queue == null ? null : new ParceledListSlice<QueueItem>(queue)); 439 } catch (RemoteException e) { 440 Log.wtf("Dead object in setQueue.", e); 441 } 442 } 443 444 /** 445 * Set the title of the play queue. The UI should display this title along 446 * with the play queue itself. 447 * e.g. "Play Queue", "Now Playing", or an album name. 448 * 449 * @param title The title of the play queue. 450 */ 451 public void setQueueTitle(@Nullable CharSequence title) { 452 try { 453 mBinder.setQueueTitle(title); 454 } catch (RemoteException e) { 455 Log.wtf("Dead object in setQueueTitle.", e); 456 } 457 } 458 459 /** 460 * Set the style of rating used by this session. Apps trying to set the 461 * rating should use this style. Must be one of the following: 462 * <ul> 463 * <li>{@link Rating#RATING_NONE}</li> 464 * <li>{@link Rating#RATING_3_STARS}</li> 465 * <li>{@link Rating#RATING_4_STARS}</li> 466 * <li>{@link Rating#RATING_5_STARS}</li> 467 * <li>{@link Rating#RATING_HEART}</li> 468 * <li>{@link Rating#RATING_PERCENTAGE}</li> 469 * <li>{@link Rating#RATING_THUMB_UP_DOWN}</li> 470 * </ul> 471 */ 472 public void setRatingType(int type) { 473 try { 474 mBinder.setRatingType(type); 475 } catch (RemoteException e) { 476 Log.e(TAG, "Error in setRatingType.", e); 477 } 478 } 479 480 /** 481 * Set some extras that can be associated with the {@link MediaSession}. No assumptions should 482 * be made as to how a {@link MediaController} will handle these extras. 483 * Keys should be fully qualified (e.g. com.example.MY_EXTRA) to avoid conflicts. 484 * 485 * @param extras The extras associated with the {@link MediaSession}. 486 */ 487 public void setExtras(@Nullable Bundle extras) { 488 try { 489 mBinder.setExtras(extras); 490 } catch (RemoteException e) { 491 Log.wtf("Dead object in setExtras.", e); 492 } 493 } 494 495 /** 496 * Notify the system that the remote volume changed. 497 * 498 * @param provider The provider that is handling volume changes. 499 * @hide 500 */ 501 public void notifyRemoteVolumeChanged(VolumeProvider provider) { 502 synchronized (mLock) { 503 if (provider == null || provider != mVolumeProvider) { 504 Log.w(TAG, "Received update from stale volume provider"); 505 return; 506 } 507 } 508 try { 509 mBinder.setCurrentVolume(provider.getCurrentVolume()); 510 } catch (RemoteException e) { 511 Log.e(TAG, "Error in notifyVolumeChanged", e); 512 } 513 } 514 515 private void dispatchPlay() { 516 postToCallback(CallbackMessageHandler.MSG_PLAY); 517 } 518 519 private void dispatchPlayFromMediaId(String mediaId, Bundle extras) { 520 postToCallback(CallbackMessageHandler.MSG_PLAY_MEDIA_ID, mediaId, extras); 521 } 522 523 private void dispatchPlayFromSearch(String query, Bundle extras) { 524 postToCallback(CallbackMessageHandler.MSG_PLAY_SEARCH, query, extras); 525 } 526 527 private void dispatchPlayFromUri(Uri uri, Bundle extras) { 528 postToCallback(CallbackMessageHandler.MSG_PLAY_URI, uri, extras); 529 } 530 531 private void dispatchSkipToItem(long id) { 532 postToCallback(CallbackMessageHandler.MSG_SKIP_TO_ITEM, id); 533 } 534 535 private void dispatchPause() { 536 postToCallback(CallbackMessageHandler.MSG_PAUSE); 537 } 538 539 private void dispatchStop() { 540 postToCallback(CallbackMessageHandler.MSG_STOP); 541 } 542 543 private void dispatchNext() { 544 postToCallback(CallbackMessageHandler.MSG_NEXT); 545 } 546 547 private void dispatchPrevious() { 548 postToCallback(CallbackMessageHandler.MSG_PREVIOUS); 549 } 550 551 private void dispatchFastForward() { 552 postToCallback(CallbackMessageHandler.MSG_FAST_FORWARD); 553 } 554 555 private void dispatchRewind() { 556 postToCallback(CallbackMessageHandler.MSG_REWIND); 557 } 558 559 private void dispatchSeekTo(long pos) { 560 postToCallback(CallbackMessageHandler.MSG_SEEK_TO, pos); 561 } 562 563 private void dispatchRate(Rating rating) { 564 postToCallback(CallbackMessageHandler.MSG_RATE, rating); 565 } 566 567 private void dispatchCustomAction(String action, Bundle args) { 568 postToCallback(CallbackMessageHandler.MSG_CUSTOM_ACTION, action, args); 569 } 570 571 private void dispatchMediaButton(Intent mediaButtonIntent) { 572 postToCallback(CallbackMessageHandler.MSG_MEDIA_BUTTON, mediaButtonIntent); 573 } 574 575 private void dispatchAdjustVolume(int direction) { 576 postToCallback(CallbackMessageHandler.MSG_ADJUST_VOLUME, direction); 577 } 578 579 private void dispatchSetVolumeTo(int volume) { 580 postToCallback(CallbackMessageHandler.MSG_SET_VOLUME, volume); 581 } 582 583 private void postToCallback(int what) { 584 postToCallback(what, null); 585 } 586 587 private void postCommand(String command, Bundle args, ResultReceiver resultCb) { 588 Command cmd = new Command(command, args, resultCb); 589 postToCallback(CallbackMessageHandler.MSG_COMMAND, cmd); 590 } 591 592 private void postToCallback(int what, Object obj) { 593 postToCallback(what, obj, null); 594 } 595 596 private void postToCallback(int what, Object obj, Bundle extras) { 597 synchronized (mLock) { 598 if (mCallback != null) { 599 mCallback.post(what, obj, extras); 600 } 601 } 602 } 603 604 /** 605 * Return true if this is considered an active playback state. 606 * 607 * @hide 608 */ 609 public static boolean isActiveState(int state) { 610 switch (state) { 611 case PlaybackState.STATE_FAST_FORWARDING: 612 case PlaybackState.STATE_REWINDING: 613 case PlaybackState.STATE_SKIPPING_TO_PREVIOUS: 614 case PlaybackState.STATE_SKIPPING_TO_NEXT: 615 case PlaybackState.STATE_BUFFERING: 616 case PlaybackState.STATE_CONNECTING: 617 case PlaybackState.STATE_PLAYING: 618 return true; 619 } 620 return false; 621 } 622 623 /** 624 * Represents an ongoing session. This may be passed to apps by the session 625 * owner to allow them to create a {@link MediaController} to communicate with 626 * the session. 627 */ 628 public static final class Token implements Parcelable { 629 630 private ISessionController mBinder; 631 632 /** 633 * @hide 634 */ 635 public Token(ISessionController binder) { 636 mBinder = binder; 637 } 638 639 @Override 640 public int describeContents() { 641 return 0; 642 } 643 644 @Override 645 public void writeToParcel(Parcel dest, int flags) { 646 dest.writeStrongBinder(mBinder.asBinder()); 647 } 648 649 @Override 650 public int hashCode() { 651 final int prime = 31; 652 int result = 1; 653 result = prime * result + ((mBinder == null) ? 0 : mBinder.asBinder().hashCode()); 654 return result; 655 } 656 657 @Override 658 public boolean equals(Object obj) { 659 if (this == obj) 660 return true; 661 if (obj == null) 662 return false; 663 if (getClass() != obj.getClass()) 664 return false; 665 Token other = (Token) obj; 666 if (mBinder == null) { 667 if (other.mBinder != null) 668 return false; 669 } else if (!mBinder.asBinder().equals(other.mBinder.asBinder())) 670 return false; 671 return true; 672 } 673 674 ISessionController getBinder() { 675 return mBinder; 676 } 677 678 public static final Parcelable.Creator<Token> CREATOR 679 = new Parcelable.Creator<Token>() { 680 @Override 681 public Token createFromParcel(Parcel in) { 682 return new Token(ISessionController.Stub.asInterface(in.readStrongBinder())); 683 } 684 685 @Override 686 public Token[] newArray(int size) { 687 return new Token[size]; 688 } 689 }; 690 } 691 692 /** 693 * Receives media buttons, transport controls, and commands from controllers 694 * and the system. A callback may be set using {@link #setCallback}. 695 */ 696 public abstract static class Callback { 697 private MediaSession mSession; 698 699 public Callback() { 700 } 701 702 /** 703 * Called when a controller has sent a command to this session. 704 * The owner of the session may handle custom commands but is not 705 * required to. 706 * 707 * @param command The command name. 708 * @param args Optional parameters for the command, may be null. 709 * @param cb A result receiver to which a result may be sent by the command, may be null. 710 */ 711 public void onCommand(@NonNull String command, @Nullable Bundle args, 712 @Nullable ResultReceiver cb) { 713 } 714 715 /** 716 * Called when a media button is pressed and this session has the 717 * highest priority or a controller sends a media button event to the 718 * session. The default behavior will call the relevant method if the 719 * action for it was set. 720 * <p> 721 * The intent will be of type {@link Intent#ACTION_MEDIA_BUTTON} with a 722 * KeyEvent in {@link Intent#EXTRA_KEY_EVENT} 723 * 724 * @param mediaButtonIntent an intent containing the KeyEvent as an 725 * extra 726 * @return True if the event was handled, false otherwise. 727 */ 728 public boolean onMediaButtonEvent(@NonNull Intent mediaButtonIntent) { 729 if (mSession != null 730 && Intent.ACTION_MEDIA_BUTTON.equals(mediaButtonIntent.getAction())) { 731 KeyEvent ke = mediaButtonIntent.getParcelableExtra(Intent.EXTRA_KEY_EVENT); 732 if (ke != null && ke.getAction() == KeyEvent.ACTION_DOWN) { 733 PlaybackState state = mSession.mPlaybackState; 734 long validActions = state == null ? 0 : state.getActions(); 735 switch (ke.getKeyCode()) { 736 case KeyEvent.KEYCODE_MEDIA_PLAY: 737 if ((validActions & PlaybackState.ACTION_PLAY) != 0) { 738 onPlay(); 739 return true; 740 } 741 break; 742 case KeyEvent.KEYCODE_MEDIA_PAUSE: 743 if ((validActions & PlaybackState.ACTION_PAUSE) != 0) { 744 onPause(); 745 return true; 746 } 747 break; 748 case KeyEvent.KEYCODE_MEDIA_NEXT: 749 if ((validActions & PlaybackState.ACTION_SKIP_TO_NEXT) != 0) { 750 onSkipToNext(); 751 return true; 752 } 753 break; 754 case KeyEvent.KEYCODE_MEDIA_PREVIOUS: 755 if ((validActions & PlaybackState.ACTION_SKIP_TO_PREVIOUS) != 0) { 756 onSkipToPrevious(); 757 return true; 758 } 759 break; 760 case KeyEvent.KEYCODE_MEDIA_STOP: 761 if ((validActions & PlaybackState.ACTION_STOP) != 0) { 762 onStop(); 763 return true; 764 } 765 break; 766 case KeyEvent.KEYCODE_MEDIA_FAST_FORWARD: 767 if ((validActions & PlaybackState.ACTION_FAST_FORWARD) != 0) { 768 onFastForward(); 769 return true; 770 } 771 break; 772 case KeyEvent.KEYCODE_MEDIA_REWIND: 773 if ((validActions & PlaybackState.ACTION_REWIND) != 0) { 774 onRewind(); 775 return true; 776 } 777 break; 778 case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE: 779 case KeyEvent.KEYCODE_HEADSETHOOK: 780 boolean isPlaying = state == null ? false 781 : state.getState() == PlaybackState.STATE_PLAYING; 782 boolean canPlay = (validActions & (PlaybackState.ACTION_PLAY_PAUSE 783 | PlaybackState.ACTION_PLAY)) != 0; 784 boolean canPause = (validActions & (PlaybackState.ACTION_PLAY_PAUSE 785 | PlaybackState.ACTION_PAUSE)) != 0; 786 if (isPlaying && canPause) { 787 onPause(); 788 return true; 789 } else if (!isPlaying && canPlay) { 790 onPlay(); 791 return true; 792 } 793 break; 794 } 795 } 796 } 797 return false; 798 } 799 800 /** 801 * Override to handle requests to begin playback. 802 */ 803 public void onPlay() { 804 } 805 806 /** 807 * Override to handle requests to play a specific mediaId that was 808 * provided by your app's {@link MediaBrowserService}. 809 */ 810 public void onPlayFromMediaId(String mediaId, Bundle extras) { 811 } 812 813 /** 814 * Override to handle requests to begin playback from a search query. An 815 * empty query indicates that the app may play any music. The 816 * implementation should attempt to make a smart choice about what to 817 * play. 818 */ 819 public void onPlayFromSearch(String query, Bundle extras) { 820 } 821 822 /** 823 * Override to handle requests to play a specific media item represented by a URI. 824 */ 825 public void onPlayFromUri(Uri uri, Bundle extras) { 826 } 827 828 /** 829 * Override to handle requests to play an item with a given id from the 830 * play queue. 831 */ 832 public void onSkipToQueueItem(long id) { 833 } 834 835 /** 836 * Override to handle requests to pause playback. 837 */ 838 public void onPause() { 839 } 840 841 /** 842 * Override to handle requests to skip to the next media item. 843 */ 844 public void onSkipToNext() { 845 } 846 847 /** 848 * Override to handle requests to skip to the previous media item. 849 */ 850 public void onSkipToPrevious() { 851 } 852 853 /** 854 * Override to handle requests to fast forward. 855 */ 856 public void onFastForward() { 857 } 858 859 /** 860 * Override to handle requests to rewind. 861 */ 862 public void onRewind() { 863 } 864 865 /** 866 * Override to handle requests to stop playback. 867 */ 868 public void onStop() { 869 } 870 871 /** 872 * Override to handle requests to seek to a specific position in ms. 873 * 874 * @param pos New position to move to, in milliseconds. 875 */ 876 public void onSeekTo(long pos) { 877 } 878 879 /** 880 * Override to handle the item being rated. 881 * 882 * @param rating 883 */ 884 public void onSetRating(@NonNull Rating rating) { 885 } 886 887 /** 888 * Called when a {@link MediaController} wants a {@link PlaybackState.CustomAction} to be 889 * performed. 890 * 891 * @param action The action that was originally sent in the 892 * {@link PlaybackState.CustomAction}. 893 * @param extras Optional extras specified by the {@link MediaController}. 894 */ 895 public void onCustomAction(@NonNull String action, @Nullable Bundle extras) { 896 } 897 } 898 899 /** 900 * @hide 901 */ 902 public static class CallbackStub extends ISessionCallback.Stub { 903 private WeakReference<MediaSession> mMediaSession; 904 905 public CallbackStub(MediaSession session) { 906 mMediaSession = new WeakReference<MediaSession>(session); 907 } 908 909 @Override 910 public void onCommand(String command, Bundle args, ResultReceiver cb) { 911 MediaSession session = mMediaSession.get(); 912 if (session != null) { 913 session.postCommand(command, args, cb); 914 } 915 } 916 917 @Override 918 public void onMediaButton(Intent mediaButtonIntent, int sequenceNumber, 919 ResultReceiver cb) { 920 MediaSession session = mMediaSession.get(); 921 try { 922 if (session != null) { 923 session.dispatchMediaButton(mediaButtonIntent); 924 } 925 } finally { 926 if (cb != null) { 927 cb.send(sequenceNumber, null); 928 } 929 } 930 } 931 932 @Override 933 public void onPlay() { 934 MediaSession session = mMediaSession.get(); 935 if (session != null) { 936 session.dispatchPlay(); 937 } 938 } 939 940 @Override 941 public void onPlayFromMediaId(String mediaId, Bundle extras) { 942 MediaSession session = mMediaSession.get(); 943 if (session != null) { 944 session.dispatchPlayFromMediaId(mediaId, extras); 945 } 946 } 947 948 @Override 949 public void onPlayFromSearch(String query, Bundle extras) { 950 MediaSession session = mMediaSession.get(); 951 if (session != null) { 952 session.dispatchPlayFromSearch(query, extras); 953 } 954 } 955 956 @Override 957 public void onPlayFromUri(Uri uri, Bundle extras) { 958 MediaSession session = mMediaSession.get(); 959 if (session != null) { 960 session.dispatchPlayFromUri(uri, extras); 961 } 962 } 963 964 @Override 965 public void onSkipToTrack(long id) { 966 MediaSession session = mMediaSession.get(); 967 if (session != null) { 968 session.dispatchSkipToItem(id); 969 } 970 } 971 972 @Override 973 public void onPause() { 974 MediaSession session = mMediaSession.get(); 975 if (session != null) { 976 session.dispatchPause(); 977 } 978 } 979 980 @Override 981 public void onStop() { 982 MediaSession session = mMediaSession.get(); 983 if (session != null) { 984 session.dispatchStop(); 985 } 986 } 987 988 @Override 989 public void onNext() { 990 MediaSession session = mMediaSession.get(); 991 if (session != null) { 992 session.dispatchNext(); 993 } 994 } 995 996 @Override 997 public void onPrevious() { 998 MediaSession session = mMediaSession.get(); 999 if (session != null) { 1000 session.dispatchPrevious(); 1001 } 1002 } 1003 1004 @Override 1005 public void onFastForward() { 1006 MediaSession session = mMediaSession.get(); 1007 if (session != null) { 1008 session.dispatchFastForward(); 1009 } 1010 } 1011 1012 @Override 1013 public void onRewind() { 1014 MediaSession session = mMediaSession.get(); 1015 if (session != null) { 1016 session.dispatchRewind(); 1017 } 1018 } 1019 1020 @Override 1021 public void onSeekTo(long pos) { 1022 MediaSession session = mMediaSession.get(); 1023 if (session != null) { 1024 session.dispatchSeekTo(pos); 1025 } 1026 } 1027 1028 @Override 1029 public void onRate(Rating rating) { 1030 MediaSession session = mMediaSession.get(); 1031 if (session != null) { 1032 session.dispatchRate(rating); 1033 } 1034 } 1035 1036 @Override 1037 public void onCustomAction(String action, Bundle args) { 1038 MediaSession session = mMediaSession.get(); 1039 if (session != null) { 1040 session.dispatchCustomAction(action, args); 1041 } 1042 } 1043 1044 @Override 1045 public void onAdjustVolume(int direction) { 1046 MediaSession session = mMediaSession.get(); 1047 if (session != null) { 1048 session.dispatchAdjustVolume(direction); 1049 } 1050 } 1051 1052 @Override 1053 public void onSetVolumeTo(int value) { 1054 MediaSession session = mMediaSession.get(); 1055 if (session != null) { 1056 session.dispatchSetVolumeTo(value); 1057 } 1058 } 1059 1060 } 1061 1062 /** 1063 * A single item that is part of the play queue. It contains a description 1064 * of the item and its id in the queue. 1065 */ 1066 public static final class QueueItem implements Parcelable { 1067 /** 1068 * This id is reserved. No items can be explicitly asigned this id. 1069 */ 1070 public static final int UNKNOWN_ID = -1; 1071 1072 private final MediaDescription mDescription; 1073 private final long mId; 1074 1075 /** 1076 * Create a new {@link MediaSession.QueueItem}. 1077 * 1078 * @param description The {@link MediaDescription} for this item. 1079 * @param id An identifier for this item. It must be unique within the 1080 * play queue and cannot be {@link #UNKNOWN_ID}. 1081 */ 1082 public QueueItem(MediaDescription description, long id) { 1083 if (description == null) { 1084 throw new IllegalArgumentException("Description cannot be null."); 1085 } 1086 if (id == UNKNOWN_ID) { 1087 throw new IllegalArgumentException("Id cannot be QueueItem.UNKNOWN_ID"); 1088 } 1089 mDescription = description; 1090 mId = id; 1091 } 1092 1093 private QueueItem(Parcel in) { 1094 mDescription = MediaDescription.CREATOR.createFromParcel(in); 1095 mId = in.readLong(); 1096 } 1097 1098 /** 1099 * Get the description for this item. 1100 */ 1101 public MediaDescription getDescription() { 1102 return mDescription; 1103 } 1104 1105 /** 1106 * Get the queue id for this item. 1107 */ 1108 public long getQueueId() { 1109 return mId; 1110 } 1111 1112 @Override 1113 public void writeToParcel(Parcel dest, int flags) { 1114 mDescription.writeToParcel(dest, flags); 1115 dest.writeLong(mId); 1116 } 1117 1118 @Override 1119 public int describeContents() { 1120 return 0; 1121 } 1122 1123 public static final Creator<MediaSession.QueueItem> CREATOR = new Creator<MediaSession.QueueItem>() { 1124 1125 @Override 1126 public MediaSession.QueueItem createFromParcel(Parcel p) { 1127 return new MediaSession.QueueItem(p); 1128 } 1129 1130 @Override 1131 public MediaSession.QueueItem[] newArray(int size) { 1132 return new MediaSession.QueueItem[size]; 1133 } 1134 }; 1135 1136 @Override 1137 public String toString() { 1138 return "MediaSession.QueueItem {" + 1139 "Description=" + mDescription + 1140 ", Id=" + mId + " }"; 1141 } 1142 } 1143 1144 private static final class Command { 1145 public final String command; 1146 public final Bundle extras; 1147 public final ResultReceiver stub; 1148 1149 public Command(String command, Bundle extras, ResultReceiver stub) { 1150 this.command = command; 1151 this.extras = extras; 1152 this.stub = stub; 1153 } 1154 } 1155 1156 private class CallbackMessageHandler extends Handler { 1157 1158 private static final int MSG_PLAY = 1; 1159 private static final int MSG_PLAY_MEDIA_ID = 2; 1160 private static final int MSG_PLAY_SEARCH = 3; 1161 private static final int MSG_SKIP_TO_ITEM = 4; 1162 private static final int MSG_PAUSE = 5; 1163 private static final int MSG_STOP = 6; 1164 private static final int MSG_NEXT = 7; 1165 private static final int MSG_PREVIOUS = 8; 1166 private static final int MSG_FAST_FORWARD = 9; 1167 private static final int MSG_REWIND = 10; 1168 private static final int MSG_SEEK_TO = 11; 1169 private static final int MSG_RATE = 12; 1170 private static final int MSG_CUSTOM_ACTION = 13; 1171 private static final int MSG_MEDIA_BUTTON = 14; 1172 private static final int MSG_COMMAND = 15; 1173 private static final int MSG_ADJUST_VOLUME = 16; 1174 private static final int MSG_SET_VOLUME = 17; 1175 private static final int MSG_PLAY_URI = 18; 1176 1177 private MediaSession.Callback mCallback; 1178 1179 public CallbackMessageHandler(Looper looper, MediaSession.Callback callback) { 1180 super(looper, null, true); 1181 mCallback = callback; 1182 } 1183 1184 public void post(int what, Object obj, Bundle bundle) { 1185 Message msg = obtainMessage(what, obj); 1186 msg.setData(bundle); 1187 msg.sendToTarget(); 1188 } 1189 1190 public void post(int what, Object obj) { 1191 obtainMessage(what, obj).sendToTarget(); 1192 } 1193 1194 public void post(int what) { 1195 post(what, null); 1196 } 1197 1198 public void post(int what, Object obj, int arg1) { 1199 obtainMessage(what, arg1, 0, obj).sendToTarget(); 1200 } 1201 1202 @Override 1203 public void handleMessage(Message msg) { 1204 VolumeProvider vp; 1205 switch (msg.what) { 1206 case MSG_PLAY: 1207 mCallback.onPlay(); 1208 break; 1209 case MSG_PLAY_MEDIA_ID: 1210 mCallback.onPlayFromMediaId((String) msg.obj, msg.getData()); 1211 break; 1212 case MSG_PLAY_SEARCH: 1213 mCallback.onPlayFromSearch((String) msg.obj, msg.getData()); 1214 break; 1215 case MSG_PLAY_URI: 1216 mCallback.onPlayFromUri((Uri) msg.obj, msg.getData()); 1217 break; 1218 case MSG_SKIP_TO_ITEM: 1219 mCallback.onSkipToQueueItem((Long) msg.obj); 1220 break; 1221 case MSG_PAUSE: 1222 mCallback.onPause(); 1223 break; 1224 case MSG_STOP: 1225 mCallback.onStop(); 1226 break; 1227 case MSG_NEXT: 1228 mCallback.onSkipToNext(); 1229 break; 1230 case MSG_PREVIOUS: 1231 mCallback.onSkipToPrevious(); 1232 break; 1233 case MSG_FAST_FORWARD: 1234 mCallback.onFastForward(); 1235 break; 1236 case MSG_REWIND: 1237 mCallback.onRewind(); 1238 break; 1239 case MSG_SEEK_TO: 1240 mCallback.onSeekTo((Long) msg.obj); 1241 break; 1242 case MSG_RATE: 1243 mCallback.onSetRating((Rating) msg.obj); 1244 break; 1245 case MSG_CUSTOM_ACTION: 1246 mCallback.onCustomAction((String) msg.obj, msg.getData()); 1247 break; 1248 case MSG_MEDIA_BUTTON: 1249 mCallback.onMediaButtonEvent((Intent) msg.obj); 1250 break; 1251 case MSG_COMMAND: 1252 Command cmd = (Command) msg.obj; 1253 mCallback.onCommand(cmd.command, cmd.extras, cmd.stub); 1254 break; 1255 case MSG_ADJUST_VOLUME: 1256 synchronized (mLock) { 1257 vp = mVolumeProvider; 1258 } 1259 if (vp != null) { 1260 vp.onAdjustVolume((int) msg.obj); 1261 } 1262 break; 1263 case MSG_SET_VOLUME: 1264 synchronized (mLock) { 1265 vp = mVolumeProvider; 1266 } 1267 if (vp != null) { 1268 vp.onSetVolumeTo((int) msg.obj); 1269 } 1270 break; 1271 } 1272 } 1273 } 1274 } 1275