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 dispatchSkipToItem(long id) { 528 postToCallback(CallbackMessageHandler.MSG_SKIP_TO_ITEM, id); 529 } 530 531 private void dispatchPause() { 532 postToCallback(CallbackMessageHandler.MSG_PAUSE); 533 } 534 535 private void dispatchStop() { 536 postToCallback(CallbackMessageHandler.MSG_STOP); 537 } 538 539 private void dispatchNext() { 540 postToCallback(CallbackMessageHandler.MSG_NEXT); 541 } 542 543 private void dispatchPrevious() { 544 postToCallback(CallbackMessageHandler.MSG_PREVIOUS); 545 } 546 547 private void dispatchFastForward() { 548 postToCallback(CallbackMessageHandler.MSG_FAST_FORWARD); 549 } 550 551 private void dispatchRewind() { 552 postToCallback(CallbackMessageHandler.MSG_REWIND); 553 } 554 555 private void dispatchSeekTo(long pos) { 556 postToCallback(CallbackMessageHandler.MSG_SEEK_TO, pos); 557 } 558 559 private void dispatchRate(Rating rating) { 560 postToCallback(CallbackMessageHandler.MSG_RATE, rating); 561 } 562 563 private void dispatchCustomAction(String action, Bundle args) { 564 postToCallback(CallbackMessageHandler.MSG_CUSTOM_ACTION, action, args); 565 } 566 567 private void dispatchMediaButton(Intent mediaButtonIntent) { 568 postToCallback(CallbackMessageHandler.MSG_MEDIA_BUTTON, mediaButtonIntent); 569 } 570 571 private void dispatchAdjustVolume(int direction) { 572 postToCallback(CallbackMessageHandler.MSG_ADJUST_VOLUME, direction); 573 } 574 575 private void dispatchSetVolumeTo(int volume) { 576 postToCallback(CallbackMessageHandler.MSG_SET_VOLUME, volume); 577 } 578 579 private void postToCallback(int what) { 580 postToCallback(what, null); 581 } 582 583 private void postCommand(String command, Bundle args, ResultReceiver resultCb) { 584 Command cmd = new Command(command, args, resultCb); 585 postToCallback(CallbackMessageHandler.MSG_COMMAND, cmd); 586 } 587 588 private void postToCallback(int what, Object obj) { 589 postToCallback(what, obj, null); 590 } 591 592 private void postToCallback(int what, Object obj, Bundle extras) { 593 synchronized (mLock) { 594 if (mCallback != null) { 595 mCallback.post(what, obj, extras); 596 } 597 } 598 } 599 600 /** 601 * Return true if this is considered an active playback state. 602 * 603 * @hide 604 */ 605 public static boolean isActiveState(int state) { 606 switch (state) { 607 case PlaybackState.STATE_FAST_FORWARDING: 608 case PlaybackState.STATE_REWINDING: 609 case PlaybackState.STATE_SKIPPING_TO_PREVIOUS: 610 case PlaybackState.STATE_SKIPPING_TO_NEXT: 611 case PlaybackState.STATE_BUFFERING: 612 case PlaybackState.STATE_CONNECTING: 613 case PlaybackState.STATE_PLAYING: 614 return true; 615 } 616 return false; 617 } 618 619 /** 620 * Represents an ongoing session. This may be passed to apps by the session 621 * owner to allow them to create a {@link MediaController} to communicate with 622 * the session. 623 */ 624 public static final class Token implements Parcelable { 625 626 private ISessionController mBinder; 627 628 /** 629 * @hide 630 */ 631 public Token(ISessionController binder) { 632 mBinder = binder; 633 } 634 635 @Override 636 public int describeContents() { 637 return 0; 638 } 639 640 @Override 641 public void writeToParcel(Parcel dest, int flags) { 642 dest.writeStrongBinder(mBinder.asBinder()); 643 } 644 645 @Override 646 public int hashCode() { 647 final int prime = 31; 648 int result = 1; 649 result = prime * result + ((mBinder == null) ? 0 : mBinder.asBinder().hashCode()); 650 return result; 651 } 652 653 @Override 654 public boolean equals(Object obj) { 655 if (this == obj) 656 return true; 657 if (obj == null) 658 return false; 659 if (getClass() != obj.getClass()) 660 return false; 661 Token other = (Token) obj; 662 if (mBinder == null) { 663 if (other.mBinder != null) 664 return false; 665 } else if (!mBinder.asBinder().equals(other.mBinder.asBinder())) 666 return false; 667 return true; 668 } 669 670 ISessionController getBinder() { 671 return mBinder; 672 } 673 674 public static final Parcelable.Creator<Token> CREATOR 675 = new Parcelable.Creator<Token>() { 676 @Override 677 public Token createFromParcel(Parcel in) { 678 return new Token(ISessionController.Stub.asInterface(in.readStrongBinder())); 679 } 680 681 @Override 682 public Token[] newArray(int size) { 683 return new Token[size]; 684 } 685 }; 686 } 687 688 /** 689 * Receives media buttons, transport controls, and commands from controllers 690 * and the system. A callback may be set using {@link #setCallback}. 691 */ 692 public abstract static class Callback { 693 private MediaSession mSession; 694 695 public Callback() { 696 } 697 698 /** 699 * Called when a controller has sent a command to this session. 700 * The owner of the session may handle custom commands but is not 701 * required to. 702 * 703 * @param command The command name. 704 * @param args Optional parameters for the command, may be null. 705 * @param cb A result receiver to which a result may be sent by the command, may be null. 706 */ 707 public void onCommand(@NonNull String command, @Nullable Bundle args, 708 @Nullable ResultReceiver cb) { 709 } 710 711 /** 712 * Called when a media button is pressed and this session has the 713 * highest priority or a controller sends a media button event to the 714 * session. The default behavior will call the relevant method if the 715 * action for it was set. 716 * <p> 717 * The intent will be of type {@link Intent#ACTION_MEDIA_BUTTON} with a 718 * KeyEvent in {@link Intent#EXTRA_KEY_EVENT} 719 * 720 * @param mediaButtonIntent an intent containing the KeyEvent as an 721 * extra 722 * @return True if the event was handled, false otherwise. 723 */ 724 public boolean onMediaButtonEvent(@NonNull Intent mediaButtonIntent) { 725 if (mSession != null 726 && Intent.ACTION_MEDIA_BUTTON.equals(mediaButtonIntent.getAction())) { 727 KeyEvent ke = mediaButtonIntent.getParcelableExtra(Intent.EXTRA_KEY_EVENT); 728 if (ke != null && ke.getAction() == KeyEvent.ACTION_DOWN) { 729 PlaybackState state = mSession.mPlaybackState; 730 long validActions = state == null ? 0 : state.getActions(); 731 switch (ke.getKeyCode()) { 732 case KeyEvent.KEYCODE_MEDIA_PLAY: 733 if ((validActions & PlaybackState.ACTION_PLAY) != 0) { 734 onPlay(); 735 return true; 736 } 737 break; 738 case KeyEvent.KEYCODE_MEDIA_PAUSE: 739 if ((validActions & PlaybackState.ACTION_PAUSE) != 0) { 740 onPause(); 741 return true; 742 } 743 break; 744 case KeyEvent.KEYCODE_MEDIA_NEXT: 745 if ((validActions & PlaybackState.ACTION_SKIP_TO_NEXT) != 0) { 746 onSkipToNext(); 747 return true; 748 } 749 break; 750 case KeyEvent.KEYCODE_MEDIA_PREVIOUS: 751 if ((validActions & PlaybackState.ACTION_SKIP_TO_PREVIOUS) != 0) { 752 onSkipToPrevious(); 753 return true; 754 } 755 break; 756 case KeyEvent.KEYCODE_MEDIA_STOP: 757 if ((validActions & PlaybackState.ACTION_STOP) != 0) { 758 onStop(); 759 return true; 760 } 761 break; 762 case KeyEvent.KEYCODE_MEDIA_FAST_FORWARD: 763 if ((validActions & PlaybackState.ACTION_FAST_FORWARD) != 0) { 764 onFastForward(); 765 return true; 766 } 767 break; 768 case KeyEvent.KEYCODE_MEDIA_REWIND: 769 if ((validActions & PlaybackState.ACTION_REWIND) != 0) { 770 onRewind(); 771 return true; 772 } 773 break; 774 case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE: 775 case KeyEvent.KEYCODE_HEADSETHOOK: 776 boolean isPlaying = state == null ? false 777 : state.getState() == PlaybackState.STATE_PLAYING; 778 boolean canPlay = (validActions & (PlaybackState.ACTION_PLAY_PAUSE 779 | PlaybackState.ACTION_PLAY)) != 0; 780 boolean canPause = (validActions & (PlaybackState.ACTION_PLAY_PAUSE 781 | PlaybackState.ACTION_PAUSE)) != 0; 782 if (isPlaying && canPause) { 783 onPause(); 784 return true; 785 } else if (!isPlaying && canPlay) { 786 onPlay(); 787 return true; 788 } 789 break; 790 } 791 } 792 } 793 return false; 794 } 795 796 /** 797 * Override to handle requests to begin playback. 798 */ 799 public void onPlay() { 800 } 801 802 /** 803 * Override to handle requests to play a specific mediaId that was 804 * provided by your app's {@link MediaBrowserService}. 805 */ 806 public void onPlayFromMediaId(String mediaId, Bundle extras) { 807 } 808 809 /** 810 * Override to handle requests to begin playback from a search query. An 811 * empty query indicates that the app may play any music. The 812 * implementation should attempt to make a smart choice about what to 813 * play. 814 */ 815 public void onPlayFromSearch(String query, Bundle extras) { 816 } 817 818 /** 819 * Override to handle requests to play an item with a given id from the 820 * play queue. 821 */ 822 public void onSkipToQueueItem(long id) { 823 } 824 825 /** 826 * Override to handle requests to pause playback. 827 */ 828 public void onPause() { 829 } 830 831 /** 832 * Override to handle requests to skip to the next media item. 833 */ 834 public void onSkipToNext() { 835 } 836 837 /** 838 * Override to handle requests to skip to the previous media item. 839 */ 840 public void onSkipToPrevious() { 841 } 842 843 /** 844 * Override to handle requests to fast forward. 845 */ 846 public void onFastForward() { 847 } 848 849 /** 850 * Override to handle requests to rewind. 851 */ 852 public void onRewind() { 853 } 854 855 /** 856 * Override to handle requests to stop playback. 857 */ 858 public void onStop() { 859 } 860 861 /** 862 * Override to handle requests to seek to a specific position in ms. 863 * 864 * @param pos New position to move to, in milliseconds. 865 */ 866 public void onSeekTo(long pos) { 867 } 868 869 /** 870 * Override to handle the item being rated. 871 * 872 * @param rating 873 */ 874 public void onSetRating(@NonNull Rating rating) { 875 } 876 877 /** 878 * Called when a {@link MediaController} wants a {@link PlaybackState.CustomAction} to be 879 * performed. 880 * 881 * @param action The action that was originally sent in the 882 * {@link PlaybackState.CustomAction}. 883 * @param extras Optional extras specified by the {@link MediaController}. 884 */ 885 public void onCustomAction(@NonNull String action, @Nullable Bundle extras) { 886 } 887 } 888 889 /** 890 * @hide 891 */ 892 public static class CallbackStub extends ISessionCallback.Stub { 893 private WeakReference<MediaSession> mMediaSession; 894 895 public CallbackStub(MediaSession session) { 896 mMediaSession = new WeakReference<MediaSession>(session); 897 } 898 899 @Override 900 public void onCommand(String command, Bundle args, ResultReceiver cb) { 901 MediaSession session = mMediaSession.get(); 902 if (session != null) { 903 session.postCommand(command, args, cb); 904 } 905 } 906 907 @Override 908 public void onMediaButton(Intent mediaButtonIntent, int sequenceNumber, 909 ResultReceiver cb) { 910 MediaSession session = mMediaSession.get(); 911 try { 912 if (session != null) { 913 session.dispatchMediaButton(mediaButtonIntent); 914 } 915 } finally { 916 if (cb != null) { 917 cb.send(sequenceNumber, null); 918 } 919 } 920 } 921 922 @Override 923 public void onPlay() { 924 MediaSession session = mMediaSession.get(); 925 if (session != null) { 926 session.dispatchPlay(); 927 } 928 } 929 930 @Override 931 public void onPlayFromMediaId(String mediaId, Bundle extras) { 932 MediaSession session = mMediaSession.get(); 933 if (session != null) { 934 session.dispatchPlayFromMediaId(mediaId, extras); 935 } 936 } 937 938 @Override 939 public void onPlayFromSearch(String query, Bundle extras) { 940 MediaSession session = mMediaSession.get(); 941 if (session != null) { 942 session.dispatchPlayFromSearch(query, extras); 943 } 944 } 945 946 @Override 947 public void onSkipToTrack(long id) { 948 MediaSession session = mMediaSession.get(); 949 if (session != null) { 950 session.dispatchSkipToItem(id); 951 } 952 } 953 954 @Override 955 public void onPause() { 956 MediaSession session = mMediaSession.get(); 957 if (session != null) { 958 session.dispatchPause(); 959 } 960 } 961 962 @Override 963 public void onStop() { 964 MediaSession session = mMediaSession.get(); 965 if (session != null) { 966 session.dispatchStop(); 967 } 968 } 969 970 @Override 971 public void onNext() { 972 MediaSession session = mMediaSession.get(); 973 if (session != null) { 974 session.dispatchNext(); 975 } 976 } 977 978 @Override 979 public void onPrevious() { 980 MediaSession session = mMediaSession.get(); 981 if (session != null) { 982 session.dispatchPrevious(); 983 } 984 } 985 986 @Override 987 public void onFastForward() { 988 MediaSession session = mMediaSession.get(); 989 if (session != null) { 990 session.dispatchFastForward(); 991 } 992 } 993 994 @Override 995 public void onRewind() { 996 MediaSession session = mMediaSession.get(); 997 if (session != null) { 998 session.dispatchRewind(); 999 } 1000 } 1001 1002 @Override 1003 public void onSeekTo(long pos) { 1004 MediaSession session = mMediaSession.get(); 1005 if (session != null) { 1006 session.dispatchSeekTo(pos); 1007 } 1008 } 1009 1010 @Override 1011 public void onRate(Rating rating) { 1012 MediaSession session = mMediaSession.get(); 1013 if (session != null) { 1014 session.dispatchRate(rating); 1015 } 1016 } 1017 1018 @Override 1019 public void onCustomAction(String action, Bundle args) { 1020 MediaSession session = mMediaSession.get(); 1021 if (session != null) { 1022 session.dispatchCustomAction(action, args); 1023 } 1024 } 1025 1026 @Override 1027 public void onAdjustVolume(int direction) { 1028 MediaSession session = mMediaSession.get(); 1029 if (session != null) { 1030 session.dispatchAdjustVolume(direction); 1031 } 1032 } 1033 1034 @Override 1035 public void onSetVolumeTo(int value) { 1036 MediaSession session = mMediaSession.get(); 1037 if (session != null) { 1038 session.dispatchSetVolumeTo(value); 1039 } 1040 } 1041 1042 } 1043 1044 /** 1045 * A single item that is part of the play queue. It contains a description 1046 * of the item and its id in the queue. 1047 */ 1048 public static final class QueueItem implements Parcelable { 1049 /** 1050 * This id is reserved. No items can be explicitly asigned this id. 1051 */ 1052 public static final int UNKNOWN_ID = -1; 1053 1054 private final MediaDescription mDescription; 1055 private final long mId; 1056 1057 /** 1058 * Create a new {@link MediaSession.QueueItem}. 1059 * 1060 * @param description The {@link MediaDescription} for this item. 1061 * @param id An identifier for this item. It must be unique within the 1062 * play queue and cannot be {@link #UNKNOWN_ID}. 1063 */ 1064 public QueueItem(MediaDescription description, long id) { 1065 if (description == null) { 1066 throw new IllegalArgumentException("Description cannot be null."); 1067 } 1068 if (id == UNKNOWN_ID) { 1069 throw new IllegalArgumentException("Id cannot be QueueItem.UNKNOWN_ID"); 1070 } 1071 mDescription = description; 1072 mId = id; 1073 } 1074 1075 private QueueItem(Parcel in) { 1076 mDescription = MediaDescription.CREATOR.createFromParcel(in); 1077 mId = in.readLong(); 1078 } 1079 1080 /** 1081 * Get the description for this item. 1082 */ 1083 public MediaDescription getDescription() { 1084 return mDescription; 1085 } 1086 1087 /** 1088 * Get the queue id for this item. 1089 */ 1090 public long getQueueId() { 1091 return mId; 1092 } 1093 1094 @Override 1095 public void writeToParcel(Parcel dest, int flags) { 1096 mDescription.writeToParcel(dest, flags); 1097 dest.writeLong(mId); 1098 } 1099 1100 @Override 1101 public int describeContents() { 1102 return 0; 1103 } 1104 1105 public static final Creator<MediaSession.QueueItem> CREATOR = new Creator<MediaSession.QueueItem>() { 1106 1107 @Override 1108 public MediaSession.QueueItem createFromParcel(Parcel p) { 1109 return new MediaSession.QueueItem(p); 1110 } 1111 1112 @Override 1113 public MediaSession.QueueItem[] newArray(int size) { 1114 return new MediaSession.QueueItem[size]; 1115 } 1116 }; 1117 1118 @Override 1119 public String toString() { 1120 return "MediaSession.QueueItem {" + 1121 "Description=" + mDescription + 1122 ", Id=" + mId + " }"; 1123 } 1124 } 1125 1126 private static final class Command { 1127 public final String command; 1128 public final Bundle extras; 1129 public final ResultReceiver stub; 1130 1131 public Command(String command, Bundle extras, ResultReceiver stub) { 1132 this.command = command; 1133 this.extras = extras; 1134 this.stub = stub; 1135 } 1136 } 1137 1138 private class CallbackMessageHandler extends Handler { 1139 1140 private static final int MSG_PLAY = 1; 1141 private static final int MSG_PLAY_MEDIA_ID = 2; 1142 private static final int MSG_PLAY_SEARCH = 3; 1143 private static final int MSG_SKIP_TO_ITEM = 4; 1144 private static final int MSG_PAUSE = 5; 1145 private static final int MSG_STOP = 6; 1146 private static final int MSG_NEXT = 7; 1147 private static final int MSG_PREVIOUS = 8; 1148 private static final int MSG_FAST_FORWARD = 9; 1149 private static final int MSG_REWIND = 10; 1150 private static final int MSG_SEEK_TO = 11; 1151 private static final int MSG_RATE = 12; 1152 private static final int MSG_CUSTOM_ACTION = 13; 1153 private static final int MSG_MEDIA_BUTTON = 14; 1154 private static final int MSG_COMMAND = 15; 1155 private static final int MSG_ADJUST_VOLUME = 16; 1156 private static final int MSG_SET_VOLUME = 17; 1157 1158 private MediaSession.Callback mCallback; 1159 1160 public CallbackMessageHandler(Looper looper, MediaSession.Callback callback) { 1161 super(looper, null, true); 1162 mCallback = callback; 1163 } 1164 1165 public void post(int what, Object obj, Bundle bundle) { 1166 Message msg = obtainMessage(what, obj); 1167 msg.setData(bundle); 1168 msg.sendToTarget(); 1169 } 1170 1171 public void post(int what, Object obj) { 1172 obtainMessage(what, obj).sendToTarget(); 1173 } 1174 1175 public void post(int what) { 1176 post(what, null); 1177 } 1178 1179 public void post(int what, Object obj, int arg1) { 1180 obtainMessage(what, arg1, 0, obj).sendToTarget(); 1181 } 1182 1183 @Override 1184 public void handleMessage(Message msg) { 1185 VolumeProvider vp; 1186 switch (msg.what) { 1187 case MSG_PLAY: 1188 mCallback.onPlay(); 1189 break; 1190 case MSG_PLAY_MEDIA_ID: 1191 mCallback.onPlayFromMediaId((String) msg.obj, msg.getData()); 1192 break; 1193 case MSG_PLAY_SEARCH: 1194 mCallback.onPlayFromSearch((String) msg.obj, msg.getData()); 1195 break; 1196 case MSG_SKIP_TO_ITEM: 1197 mCallback.onSkipToQueueItem((Long) msg.obj); 1198 break; 1199 case MSG_PAUSE: 1200 mCallback.onPause(); 1201 break; 1202 case MSG_STOP: 1203 mCallback.onStop(); 1204 break; 1205 case MSG_NEXT: 1206 mCallback.onSkipToNext(); 1207 break; 1208 case MSG_PREVIOUS: 1209 mCallback.onSkipToPrevious(); 1210 break; 1211 case MSG_FAST_FORWARD: 1212 mCallback.onFastForward(); 1213 break; 1214 case MSG_REWIND: 1215 mCallback.onRewind(); 1216 break; 1217 case MSG_SEEK_TO: 1218 mCallback.onSeekTo((Long) msg.obj); 1219 break; 1220 case MSG_RATE: 1221 mCallback.onSetRating((Rating) msg.obj); 1222 break; 1223 case MSG_CUSTOM_ACTION: 1224 mCallback.onCustomAction((String) msg.obj, msg.getData()); 1225 break; 1226 case MSG_MEDIA_BUTTON: 1227 mCallback.onMediaButtonEvent((Intent) msg.obj); 1228 break; 1229 case MSG_COMMAND: 1230 Command cmd = (Command) msg.obj; 1231 mCallback.onCommand(cmd.command, cmd.extras, cmd.stub); 1232 break; 1233 case MSG_ADJUST_VOLUME: 1234 synchronized (mLock) { 1235 vp = mVolumeProvider; 1236 } 1237 if (vp != null) { 1238 vp.onAdjustVolume((int) msg.obj); 1239 } 1240 break; 1241 case MSG_SET_VOLUME: 1242 synchronized (mLock) { 1243 vp = mVolumeProvider; 1244 } 1245 if (vp != null) { 1246 vp.onSetVolumeTo((int) msg.obj); 1247 } 1248 break; 1249 } 1250 } 1251 } 1252 } 1253
