MediaBrowser.java revision b646eab3f53ecf5693a8ca37d334fb911b8db7d6
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 17package android.media.browse; 18 19import android.annotation.IntDef; 20import android.annotation.NonNull; 21import android.annotation.Nullable; 22import android.content.ComponentName; 23import android.content.Context; 24import android.content.Intent; 25import android.content.ServiceConnection; 26import android.content.pm.ParceledListSlice; 27import android.media.MediaDescription; 28import android.media.session.MediaController; 29import android.media.session.MediaSession; 30import android.os.Bundle; 31import android.os.Handler; 32import android.os.IBinder; 33import android.os.Parcel; 34import android.os.Parcelable; 35import android.os.RemoteException; 36import android.os.ResultReceiver; 37import android.service.media.IMediaBrowserService; 38import android.service.media.IMediaBrowserServiceCallbacks; 39import android.service.media.MediaBrowserService; 40import android.text.TextUtils; 41import android.util.ArrayMap; 42import android.util.Log; 43 44import java.lang.annotation.Retention; 45import java.lang.annotation.RetentionPolicy; 46import java.lang.ref.WeakReference; 47import java.util.ArrayList; 48import java.util.List; 49import java.util.Map.Entry; 50 51/** 52 * Browses media content offered by a link MediaBrowserService. 53 * <p> 54 * This object is not thread-safe. All calls should happen on the thread on which the browser 55 * was constructed. 56 * </p> 57 * <h3>Standard Extra Data</h3> 58 * 59 * <p>These are the current standard fields that can be used as extra data via 60 * {@link #subscribe(String, Bundle, SubscriptionCallback)}, 61 * {@link #unsubscribe(String, SubscriptionCallback)}, and 62 * {@link SubscriptionCallback#onChildrenLoaded(String, List, Bundle)}. 63 * 64 * <ul> 65 * <li> {@link #EXTRA_PAGE} 66 * <li> {@link #EXTRA_PAGE_SIZE} 67 * </ul> 68 */ 69public final class MediaBrowser { 70 private static final String TAG = "MediaBrowser"; 71 private static final boolean DBG = false; 72 73 /** 74 * Used as an int extra field to denote the page number to subscribe. 75 * The value of {@code EXTRA_PAGE} should be greater than or equal to 0. 76 * 77 * @see #EXTRA_PAGE_SIZE 78 */ 79 public static final String EXTRA_PAGE = "android.media.browse.extra.PAGE"; 80 81 /** 82 * Used as an int extra field to denote the number of media items in a page. 83 * The value of {@code EXTRA_PAGE_SIZE} should be greater than or equal to 1. 84 * 85 * @see #EXTRA_PAGE 86 */ 87 public static final String EXTRA_PAGE_SIZE = "android.media.browse.extra.PAGE_SIZE"; 88 89 private static final int CONNECT_STATE_DISCONNECTED = 0; 90 private static final int CONNECT_STATE_CONNECTING = 1; 91 private static final int CONNECT_STATE_CONNECTED = 2; 92 private static final int CONNECT_STATE_SUSPENDED = 3; 93 94 private final Context mContext; 95 private final ComponentName mServiceComponent; 96 private final ConnectionCallback mCallback; 97 private final Bundle mRootHints; 98 private final Handler mHandler = new Handler(); 99 private final ArrayMap<String, Subscription> mSubscriptions = new ArrayMap<>(); 100 101 private volatile int mState = CONNECT_STATE_DISCONNECTED; 102 private volatile String mRootId; 103 private volatile MediaSession.Token mMediaSessionToken; 104 private volatile Bundle mExtras; 105 106 private MediaServiceConnection mServiceConnection; 107 private IMediaBrowserService mServiceBinder; 108 private IMediaBrowserServiceCallbacks mServiceCallbacks; 109 110 /** 111 * Creates a media browser for the specified media browse service. 112 * 113 * @param context The context. 114 * @param serviceComponent The component name of the media browse service. 115 * @param callback The connection callback. 116 * @param rootHints An optional bundle of service-specific arguments to send 117 * to the media browse service when connecting and retrieving the root id 118 * for browsing, or null if none. The contents of this bundle may affect 119 * the information returned when browsing. 120 * @see android.service.media.MediaBrowserService.BrowserRoot#EXTRA_RECENT 121 * @see android.service.media.MediaBrowserService.BrowserRoot#EXTRA_OFFLINE 122 * @see android.service.media.MediaBrowserService.BrowserRoot#EXTRA_SUGGESTED 123 */ 124 public MediaBrowser(Context context, ComponentName serviceComponent, 125 ConnectionCallback callback, Bundle rootHints) { 126 if (context == null) { 127 throw new IllegalArgumentException("context must not be null"); 128 } 129 if (serviceComponent == null) { 130 throw new IllegalArgumentException("service component must not be null"); 131 } 132 if (callback == null) { 133 throw new IllegalArgumentException("connection callback must not be null"); 134 } 135 mContext = context; 136 mServiceComponent = serviceComponent; 137 mCallback = callback; 138 mRootHints = rootHints; 139 } 140 141 /** 142 * Connects to the media browse service. 143 * <p> 144 * The connection callback specified in the constructor will be invoked 145 * when the connection completes or fails. 146 * </p> 147 */ 148 public void connect() { 149 if (mState != CONNECT_STATE_DISCONNECTED) { 150 throw new IllegalStateException("connect() called while not disconnected (state=" 151 + getStateLabel(mState) + ")"); 152 } 153 // TODO: remove this extra check. 154 if (DBG) { 155 if (mServiceConnection != null) { 156 throw new RuntimeException("mServiceConnection should be null. Instead it is " 157 + mServiceConnection); 158 } 159 } 160 if (mServiceBinder != null) { 161 throw new RuntimeException("mServiceBinder should be null. Instead it is " 162 + mServiceBinder); 163 } 164 if (mServiceCallbacks != null) { 165 throw new RuntimeException("mServiceCallbacks should be null. Instead it is " 166 + mServiceCallbacks); 167 } 168 169 mState = CONNECT_STATE_CONNECTING; 170 171 final Intent intent = new Intent(MediaBrowserService.SERVICE_INTERFACE); 172 intent.setComponent(mServiceComponent); 173 174 final ServiceConnection thisConnection = mServiceConnection = new MediaServiceConnection(); 175 176 boolean bound = false; 177 try { 178 bound = mContext.bindService(intent, mServiceConnection, Context.BIND_AUTO_CREATE); 179 } catch (Exception ex) { 180 Log.e(TAG, "Failed binding to service " + mServiceComponent); 181 } 182 183 if (!bound) { 184 // Tell them that it didn't work. We are already on the main thread, 185 // but we don't want to do callbacks inside of connect(). So post it, 186 // and then check that we are on the same ServiceConnection. We know 187 // we won't also get an onServiceConnected or onServiceDisconnected, 188 // so we won't be doing double callbacks. 189 mHandler.post(new Runnable() { 190 @Override 191 public void run() { 192 // Ensure that nobody else came in or tried to connect again. 193 if (thisConnection == mServiceConnection) { 194 forceCloseConnection(); 195 mCallback.onConnectionFailed(); 196 } 197 } 198 }); 199 } 200 201 if (DBG) { 202 Log.d(TAG, "connect..."); 203 dump(); 204 } 205 } 206 207 /** 208 * Disconnects from the media browse service. 209 * After this, no more callbacks will be received. 210 */ 211 public void disconnect() { 212 // It's ok to call this any state, because allowing this lets apps not have 213 // to check isConnected() unnecessarily. They won't appreciate the extra 214 // assertions for this. We do everything we can here to go back to a sane state. 215 mHandler.post(new Runnable() { 216 @Override 217 public void run() { 218 if (mServiceCallbacks != null) { 219 try { 220 mServiceBinder.disconnect(mServiceCallbacks); 221 } catch (RemoteException ex) { 222 // We are disconnecting anyway. Log, just for posterity but it's not 223 // a big problem. 224 Log.w(TAG, "RemoteException during connect for " + mServiceComponent); 225 } 226 } 227 forceCloseConnection(); 228 if (DBG) { 229 Log.d(TAG, "disconnect..."); 230 dump(); 231 } 232 } 233 }); 234 } 235 236 /** 237 * Null out the variables and unbind from the service. This doesn't include 238 * calling disconnect on the service, because we only try to do that in the 239 * clean shutdown cases. 240 * <p> 241 * Everywhere that calls this EXCEPT for disconnect() should follow it with 242 * a call to mCallback.onConnectionFailed(). Disconnect doesn't do that callback 243 * for a clean shutdown, but everywhere else is a dirty shutdown and should 244 * notify the app. 245 */ 246 private void forceCloseConnection() { 247 if (mServiceConnection != null) { 248 mContext.unbindService(mServiceConnection); 249 } 250 mState = CONNECT_STATE_DISCONNECTED; 251 mServiceConnection = null; 252 mServiceBinder = null; 253 mServiceCallbacks = null; 254 mRootId = null; 255 mMediaSessionToken = null; 256 } 257 258 /** 259 * Returns whether the browser is connected to the service. 260 */ 261 public boolean isConnected() { 262 return mState == CONNECT_STATE_CONNECTED; 263 } 264 265 /** 266 * Gets the service component that the media browser is connected to. 267 */ 268 public @NonNull ComponentName getServiceComponent() { 269 if (!isConnected()) { 270 throw new IllegalStateException("getServiceComponent() called while not connected" + 271 " (state=" + mState + ")"); 272 } 273 return mServiceComponent; 274 } 275 276 /** 277 * Gets the root id. 278 * <p> 279 * Note that the root id may become invalid or change when the 280 * browser is disconnected. 281 * </p> 282 * 283 * @throws IllegalStateException if not connected. 284 */ 285 public @NonNull String getRoot() { 286 if (!isConnected()) { 287 throw new IllegalStateException("getRoot() called while not connected (state=" 288 + getStateLabel(mState) + ")"); 289 } 290 return mRootId; 291 } 292 293 /** 294 * Gets any extras for the media service. 295 * 296 * @throws IllegalStateException if not connected. 297 */ 298 public @Nullable Bundle getExtras() { 299 if (!isConnected()) { 300 throw new IllegalStateException("getExtras() called while not connected (state=" 301 + getStateLabel(mState) + ")"); 302 } 303 return mExtras; 304 } 305 306 /** 307 * Gets the media session token associated with the media browser. 308 * <p> 309 * Note that the session token may become invalid or change when the 310 * browser is disconnected. 311 * </p> 312 * 313 * @return The session token for the browser, never null. 314 * 315 * @throws IllegalStateException if not connected. 316 */ 317 public @NonNull MediaSession.Token getSessionToken() { 318 if (!isConnected()) { 319 throw new IllegalStateException("getSessionToken() called while not connected (state=" 320 + mState + ")"); 321 } 322 return mMediaSessionToken; 323 } 324 325 /** 326 * Queries for information about the media items that are contained within 327 * the specified id and subscribes to receive updates when they change. 328 * <p> 329 * The list of subscriptions is maintained even when not connected and is 330 * restored after the reconnection. It is ok to subscribe while not connected 331 * but the results will not be returned until the connection completes. 332 * </p> 333 * <p> 334 * If the id is already subscribed with a different callback then the new 335 * callback will replace the previous one and the child data will be 336 * reloaded. 337 * </p> 338 * 339 * @param parentId The id of the parent media item whose list of children 340 * will be subscribed. 341 * @param callback The callback to receive the list of children. 342 */ 343 public void subscribe(@NonNull String parentId, @NonNull SubscriptionCallback callback) { 344 subscribeInternal(parentId, null, callback); 345 } 346 347 /** 348 * Queries with service-specific arguments for information about the media items 349 * that are contained within the specified id and subscribes to receive updates 350 * when they change. 351 * <p> 352 * The list of subscriptions is maintained even when not connected and is 353 * restored after the reconnection. It is ok to subscribe while not connected 354 * but the results will not be returned until the connection completes. 355 * </p> 356 * <p> 357 * If the id is already subscribed with a different callback then the new 358 * callback will replace the previous one and the child data will be 359 * reloaded. 360 * </p> 361 * 362 * @param parentId The id of the parent media item whose list of children 363 * will be subscribed. 364 * @param options A bundle of service-specific arguments to send to the media 365 * browse service. The contents of this bundle may affect the 366 * information returned when browsing. 367 * @param callback The callback to receive the list of children. 368 */ 369 public void subscribe(@NonNull String parentId, @NonNull Bundle options, 370 @NonNull SubscriptionCallback callback) { 371 if (options == null) { 372 throw new IllegalArgumentException("options are null"); 373 } 374 subscribeInternal(parentId, new Bundle(options), callback); 375 } 376 377 /** 378 * Unsubscribes for changes to the children of the specified media id. 379 * <p> 380 * The query callback will no longer be invoked for results associated with 381 * this id once this method returns. 382 * </p> 383 * 384 * @param parentId The id of the parent media item whose list of children 385 * will be unsubscribed. 386 */ 387 public void unsubscribe(@NonNull String parentId) { 388 unsubscribeInternal(parentId, null); 389 } 390 391 /** 392 * Unsubscribes for changes to the children of the specified media id through a callback. 393 * <p> 394 * The query callback will no longer be invoked for results associated with 395 * this id once this method returns. 396 * </p> 397 * 398 * @param parentId The id of the parent media item whose list of children 399 * will be unsubscribed. 400 * @param callback A callback sent to the media browse service to subscribe. 401 */ 402 public void unsubscribe(@NonNull String parentId, @NonNull SubscriptionCallback callback) { 403 if (callback == null) { 404 throw new IllegalArgumentException("callback is null"); 405 } 406 unsubscribeInternal(parentId, callback); 407 } 408 409 /** 410 * Retrieves a specific {@link MediaItem} from the connected service. Not 411 * all services may support this, so falling back to subscribing to the 412 * parent's id should be used when unavailable. 413 * 414 * @param mediaId The id of the item to retrieve. 415 * @param cb The callback to receive the result on. 416 */ 417 public void getItem(final @NonNull String mediaId, @NonNull final ItemCallback cb) { 418 if (TextUtils.isEmpty(mediaId)) { 419 throw new IllegalArgumentException("mediaId is empty."); 420 } 421 if (cb == null) { 422 throw new IllegalArgumentException("cb is null."); 423 } 424 if (mState != CONNECT_STATE_CONNECTED) { 425 Log.i(TAG, "Not connected, unable to retrieve the MediaItem."); 426 mHandler.post(new Runnable() { 427 @Override 428 public void run() { 429 cb.onError(mediaId); 430 } 431 }); 432 return; 433 } 434 ResultReceiver receiver = new ResultReceiver(mHandler) { 435 @Override 436 protected void onReceiveResult(int resultCode, Bundle resultData) { 437 if (resultCode != 0 || resultData == null 438 || !resultData.containsKey(MediaBrowserService.KEY_MEDIA_ITEM)) { 439 cb.onError(mediaId); 440 return; 441 } 442 Parcelable item = resultData.getParcelable(MediaBrowserService.KEY_MEDIA_ITEM); 443 if (!(item instanceof MediaItem)) { 444 cb.onError(mediaId); 445 return; 446 } 447 cb.onItemLoaded((MediaItem)item); 448 } 449 }; 450 try { 451 mServiceBinder.getMediaItem(mediaId, receiver); 452 } catch (RemoteException e) { 453 Log.i(TAG, "Remote error getting media item."); 454 mHandler.post(new Runnable() { 455 @Override 456 public void run() { 457 cb.onError(mediaId); 458 } 459 }); 460 } 461 } 462 463 private void subscribeInternal(String parentId, Bundle options, SubscriptionCallback callback) { 464 // Check arguments. 465 if (TextUtils.isEmpty(parentId)) { 466 throw new IllegalArgumentException("parentId is empty."); 467 } 468 if (callback == null) { 469 throw new IllegalArgumentException("callback is null"); 470 } 471 // Update or create the subscription. 472 Subscription sub = mSubscriptions.get(parentId); 473 if (sub == null) { 474 sub = new Subscription(); 475 mSubscriptions.put(parentId, sub); 476 } 477 sub.putCallback(options, callback); 478 479 // If we are connected, tell the service that we are watching. If we aren't connected, 480 // the service will be told when we connect. 481 if (mState == CONNECT_STATE_CONNECTED) { 482 try { 483 // NOTE: Do not call addSubscriptionWithOptions when options are null. Otherwise, 484 // it will break the action of support library which expects addSubscription will 485 // be called when options are null. 486 if (options == null) { 487 mServiceBinder.addSubscription(parentId, mServiceCallbacks); 488 } else { 489 mServiceBinder.addSubscriptionWithOptions(parentId, options, mServiceCallbacks); 490 } 491 } catch (RemoteException ex) { 492 // Process is crashing. We will disconnect, and upon reconnect we will 493 // automatically reregister. So nothing to do here. 494 Log.d(TAG, "addSubscription failed with RemoteException parentId=" + parentId); 495 } 496 } 497 } 498 499 private void unsubscribeInternal(String parentId, SubscriptionCallback callback) { 500 // Check arguments. 501 if (TextUtils.isEmpty(parentId)) { 502 throw new IllegalArgumentException("parentId is empty."); 503 } 504 505 // Remove from our list. 506 Subscription sub = mSubscriptions.get(parentId); 507 508 // Tell the service if necessary. 509 if (mState == CONNECT_STATE_CONNECTED && sub != null) { 510 try { 511 if (callback == null) { 512 mServiceBinder.removeSubscription(parentId, mServiceCallbacks); 513 } else { 514 final List<SubscriptionCallback> callbacks = sub.getCallbacks(); 515 final List<Bundle> optionsList = sub.getOptionsList(); 516 for (int i = callbacks.size() - 1; i >= 0; --i) { 517 if (callbacks.get(i) == callback) { 518 mServiceBinder.removeSubscriptionWithOptions( 519 parentId, optionsList.get(i), mServiceCallbacks); 520 callbacks.remove(i); 521 optionsList.remove(i); 522 } 523 } 524 } 525 } catch (RemoteException ex) { 526 // Process is crashing. We will disconnect, and upon reconnect we will 527 // automatically reregister. So nothing to do here. 528 Log.d(TAG, "removeSubscription failed with RemoteException parentId=" + parentId); 529 } 530 } 531 532 if (sub != null && (sub.isEmpty() || callback == null)) { 533 mSubscriptions.remove(parentId); 534 } 535 } 536 537 /** 538 * For debugging. 539 */ 540 private static String getStateLabel(int state) { 541 switch (state) { 542 case CONNECT_STATE_DISCONNECTED: 543 return "CONNECT_STATE_DISCONNECTED"; 544 case CONNECT_STATE_CONNECTING: 545 return "CONNECT_STATE_CONNECTING"; 546 case CONNECT_STATE_CONNECTED: 547 return "CONNECT_STATE_CONNECTED"; 548 case CONNECT_STATE_SUSPENDED: 549 return "CONNECT_STATE_SUSPENDED"; 550 default: 551 return "UNKNOWN/" + state; 552 } 553 } 554 555 private final void onServiceConnected(final IMediaBrowserServiceCallbacks callback, 556 final String root, final MediaSession.Token session, final Bundle extra) { 557 mHandler.post(new Runnable() { 558 @Override 559 public void run() { 560 // Check to make sure there hasn't been a disconnect or a different 561 // ServiceConnection. 562 if (!isCurrent(callback, "onConnect")) { 563 return; 564 } 565 // Don't allow them to call us twice. 566 if (mState != CONNECT_STATE_CONNECTING) { 567 Log.w(TAG, "onConnect from service while mState=" 568 + getStateLabel(mState) + "... ignoring"); 569 return; 570 } 571 mRootId = root; 572 mMediaSessionToken = session; 573 mExtras = extra; 574 mState = CONNECT_STATE_CONNECTED; 575 576 if (DBG) { 577 Log.d(TAG, "ServiceCallbacks.onConnect..."); 578 dump(); 579 } 580 mCallback.onConnected(); 581 582 // we may receive some subscriptions before we are connected, so re-subscribe 583 // everything now 584 for (Entry<String, Subscription> subscriptionEntry : mSubscriptions.entrySet()) { 585 String id = subscriptionEntry.getKey(); 586 Subscription sub = subscriptionEntry.getValue(); 587 for (Bundle options : sub.getOptionsList()) { 588 try { 589 // NOTE: Do not call addSubscriptionWithOptions when options are null. 590 // Otherwise, it will break the action of support library which expects 591 // addSubscription will be called when options are null. 592 if (options == null) { 593 mServiceBinder.addSubscription(id, mServiceCallbacks); 594 } else { 595 mServiceBinder.addSubscriptionWithOptions( 596 id, options, mServiceCallbacks); 597 } 598 } catch (RemoteException ex) { 599 // Process is crashing. We will disconnect, and upon reconnect we will 600 // automatically reregister. So nothing to do here. 601 Log.d(TAG, "addSubscription failed with RemoteException parentId=" 602 + id); 603 } 604 } 605 } 606 } 607 }); 608 } 609 610 private final void onConnectionFailed(final IMediaBrowserServiceCallbacks callback) { 611 mHandler.post(new Runnable() { 612 @Override 613 public void run() { 614 Log.e(TAG, "onConnectFailed for " + mServiceComponent); 615 616 // Check to make sure there hasn't been a disconnect or a different 617 // ServiceConnection. 618 if (!isCurrent(callback, "onConnectFailed")) { 619 return; 620 } 621 // Don't allow them to call us twice. 622 if (mState != CONNECT_STATE_CONNECTING) { 623 Log.w(TAG, "onConnect from service while mState=" 624 + getStateLabel(mState) + "... ignoring"); 625 return; 626 } 627 628 // Clean up 629 forceCloseConnection(); 630 631 // Tell the app. 632 mCallback.onConnectionFailed(); 633 } 634 }); 635 } 636 637 private final void onLoadChildren(final IMediaBrowserServiceCallbacks callback, 638 final String parentId, final ParceledListSlice list, final Bundle options) { 639 mHandler.post(new Runnable() { 640 @Override 641 public void run() { 642 // Check that there hasn't been a disconnect or a different 643 // ServiceConnection. 644 if (!isCurrent(callback, "onLoadChildren")) { 645 return; 646 } 647 648 if (DBG) { 649 Log.d(TAG, "onLoadChildren for " + mServiceComponent + " id=" + parentId); 650 } 651 652 // Check that the subscription is still subscribed. 653 final Subscription subscription = mSubscriptions.get(parentId); 654 if (subscription != null) { 655 // Tell the app. 656 SubscriptionCallback subscriptionCallback = subscription.getCallback(options); 657 if (subscriptionCallback != null) { 658 List<MediaItem> data = list == null ? null : list.getList(); 659 if (options == null) { 660 if (data == null) { 661 subscriptionCallback.onError(parentId); 662 } else { 663 subscriptionCallback.onChildrenLoaded(parentId, data); 664 } 665 } else { 666 if (data == null) { 667 subscriptionCallback.onError(parentId, options); 668 } else { 669 subscriptionCallback.onChildrenLoaded(parentId, data, options); 670 } 671 } 672 return; 673 } 674 } 675 if (DBG) { 676 Log.d(TAG, "onLoadChildren for id that isn't subscribed id=" + parentId); 677 } 678 } 679 }); 680 } 681 682 /** 683 * Return true if {@code callback} is the current ServiceCallbacks. Also logs if it's not. 684 */ 685 private boolean isCurrent(IMediaBrowserServiceCallbacks callback, String funcName) { 686 if (mServiceCallbacks != callback) { 687 if (mState != CONNECT_STATE_DISCONNECTED) { 688 Log.i(TAG, funcName + " for " + mServiceComponent + " with mServiceConnection=" 689 + mServiceCallbacks + " this=" + this); 690 } 691 return false; 692 } 693 return true; 694 } 695 696 private ServiceCallbacks getNewServiceCallbacks() { 697 return new ServiceCallbacks(this); 698 } 699 700 /** 701 * Log internal state. 702 * @hide 703 */ 704 void dump() { 705 Log.d(TAG, "MediaBrowser..."); 706 Log.d(TAG, " mServiceComponent=" + mServiceComponent); 707 Log.d(TAG, " mCallback=" + mCallback); 708 Log.d(TAG, " mRootHints=" + mRootHints); 709 Log.d(TAG, " mState=" + getStateLabel(mState)); 710 Log.d(TAG, " mServiceConnection=" + mServiceConnection); 711 Log.d(TAG, " mServiceBinder=" + mServiceBinder); 712 Log.d(TAG, " mServiceCallbacks=" + mServiceCallbacks); 713 Log.d(TAG, " mRootId=" + mRootId); 714 Log.d(TAG, " mMediaSessionToken=" + mMediaSessionToken); 715 } 716 717 /** 718 * A class with information on a single media item for use in browsing media. 719 */ 720 public static class MediaItem implements Parcelable { 721 private final int mFlags; 722 private final MediaDescription mDescription; 723 724 /** @hide */ 725 @Retention(RetentionPolicy.SOURCE) 726 @IntDef(flag=true, value = { FLAG_BROWSABLE, FLAG_PLAYABLE }) 727 public @interface Flags { } 728 729 /** 730 * Flag: Indicates that the item has children of its own. 731 */ 732 public static final int FLAG_BROWSABLE = 1 << 0; 733 734 /** 735 * Flag: Indicates that the item is playable. 736 * <p> 737 * The id of this item may be passed to 738 * {@link MediaController.TransportControls#playFromMediaId(String, Bundle)} 739 * to start playing it. 740 * </p> 741 */ 742 public static final int FLAG_PLAYABLE = 1 << 1; 743 744 /** 745 * Create a new MediaItem for use in browsing media. 746 * @param description The description of the media, which must include a 747 * media id. 748 * @param flags The flags for this item. 749 */ 750 public MediaItem(@NonNull MediaDescription description, @Flags int flags) { 751 if (description == null) { 752 throw new IllegalArgumentException("description cannot be null"); 753 } 754 if (TextUtils.isEmpty(description.getMediaId())) { 755 throw new IllegalArgumentException("description must have a non-empty media id"); 756 } 757 mFlags = flags; 758 mDescription = description; 759 } 760 761 /** 762 * Private constructor. 763 */ 764 private MediaItem(Parcel in) { 765 mFlags = in.readInt(); 766 mDescription = MediaDescription.CREATOR.createFromParcel(in); 767 } 768 769 @Override 770 public int describeContents() { 771 return 0; 772 } 773 774 @Override 775 public void writeToParcel(Parcel out, int flags) { 776 out.writeInt(mFlags); 777 mDescription.writeToParcel(out, flags); 778 } 779 780 @Override 781 public String toString() { 782 final StringBuilder sb = new StringBuilder("MediaItem{"); 783 sb.append("mFlags=").append(mFlags); 784 sb.append(", mDescription=").append(mDescription); 785 sb.append('}'); 786 return sb.toString(); 787 } 788 789 public static final Parcelable.Creator<MediaItem> CREATOR = 790 new Parcelable.Creator<MediaItem>() { 791 @Override 792 public MediaItem createFromParcel(Parcel in) { 793 return new MediaItem(in); 794 } 795 796 @Override 797 public MediaItem[] newArray(int size) { 798 return new MediaItem[size]; 799 } 800 }; 801 802 /** 803 * Gets the flags of the item. 804 */ 805 public @Flags int getFlags() { 806 return mFlags; 807 } 808 809 /** 810 * Returns whether this item is browsable. 811 * @see #FLAG_BROWSABLE 812 */ 813 public boolean isBrowsable() { 814 return (mFlags & FLAG_BROWSABLE) != 0; 815 } 816 817 /** 818 * Returns whether this item is playable. 819 * @see #FLAG_PLAYABLE 820 */ 821 public boolean isPlayable() { 822 return (mFlags & FLAG_PLAYABLE) != 0; 823 } 824 825 /** 826 * Returns the description of the media. 827 */ 828 public @NonNull MediaDescription getDescription() { 829 return mDescription; 830 } 831 832 /** 833 * Returns the media id for this item. 834 */ 835 public @NonNull String getMediaId() { 836 return mDescription.getMediaId(); 837 } 838 } 839 840 /** 841 * Callbacks for connection related events. 842 */ 843 public static class ConnectionCallback { 844 /** 845 * Invoked after {@link MediaBrowser#connect()} when the request has successfully completed. 846 */ 847 public void onConnected() { 848 } 849 850 /** 851 * Invoked when the client is disconnected from the media browser. 852 */ 853 public void onConnectionSuspended() { 854 } 855 856 /** 857 * Invoked when the connection to the media browser failed. 858 */ 859 public void onConnectionFailed() { 860 } 861 } 862 863 /** 864 * Callbacks for subscription related events. 865 */ 866 public static abstract class SubscriptionCallback { 867 /** 868 * Called when the list of children is loaded or updated. 869 * 870 * @param parentId The media id of the parent media item. 871 * @param children The children which were loaded. 872 */ 873 public void onChildrenLoaded(@NonNull String parentId, @NonNull List<MediaItem> children) { 874 } 875 876 /** 877 * Called when the list of children is loaded or updated. 878 * 879 * @param parentId The media id of the parent media item. 880 * @param children The children which were loaded. 881 * @param options A bundle of service-specific arguments sent to the media 882 * browse service. The contents of this bundle may affect the 883 * information returned when browsing. 884 */ 885 public void onChildrenLoaded(@NonNull String parentId, @NonNull List<MediaItem> children, 886 @NonNull Bundle options) { 887 } 888 889 /** 890 * Called when the id doesn't exist or other errors in subscribing. 891 * <p> 892 * If this is called, the subscription remains until {@link MediaBrowser#unsubscribe} 893 * called, because some errors may heal themselves. 894 * </p> 895 * 896 * @param parentId The media id of the parent media item whose children could 897 * not be loaded. 898 */ 899 public void onError(@NonNull String parentId) { 900 } 901 902 /** 903 * Called when the id doesn't exist or other errors in subscribing. 904 * <p> 905 * If this is called, the subscription remains until {@link MediaBrowser#unsubscribe} 906 * called, because some errors may heal themselves. 907 * </p> 908 * 909 * @param parentId The media id of the parent media item whose children could 910 * not be loaded. 911 * @param options A bundle of service-specific arguments sent to the media 912 * browse service. 913 */ 914 public void onError(@NonNull String parentId, @NonNull Bundle options) { 915 } 916 } 917 918 /** 919 * Callback for receiving the result of {@link #getItem}. 920 */ 921 public static abstract class ItemCallback { 922 /** 923 * Called when the item has been returned by the browser service. 924 * 925 * @param item The item that was returned or null if it doesn't exist. 926 */ 927 public void onItemLoaded(MediaItem item) { 928 } 929 930 /** 931 * Called when the item doesn't exist or there was an error retrieving it. 932 * 933 * @param itemId The media id of the media item which could not be loaded. 934 */ 935 public void onError(@NonNull String itemId) { 936 } 937 } 938 939 /** 940 * ServiceConnection to the other app. 941 */ 942 private class MediaServiceConnection implements ServiceConnection { 943 @Override 944 public void onServiceConnected(final ComponentName name, final IBinder binder) { 945 postOrRun(new Runnable() { 946 @Override 947 public void run() { 948 if (DBG) { 949 Log.d(TAG, "MediaServiceConnection.onServiceConnected name=" + name 950 + " binder=" + binder); 951 dump(); 952 } 953 954 // Make sure we are still the current connection, and that they haven't called 955 // disconnect(). 956 if (!isCurrent("onServiceConnected")) { 957 return; 958 } 959 960 // Save their binder 961 mServiceBinder = IMediaBrowserService.Stub.asInterface(binder); 962 963 // We make a new mServiceCallbacks each time we connect so that we can drop 964 // responses from previous connections. 965 mServiceCallbacks = getNewServiceCallbacks(); 966 mState = CONNECT_STATE_CONNECTING; 967 968 // Call connect, which is async. When we get a response from that we will 969 // say that we're connected. 970 try { 971 if (DBG) { 972 Log.d(TAG, "ServiceCallbacks.onConnect..."); 973 dump(); 974 } 975 mServiceBinder.connect(mContext.getPackageName(), mRootHints, 976 mServiceCallbacks); 977 } catch (RemoteException ex) { 978 // Connect failed, which isn't good. But the auto-reconnect on the service 979 // will take over and we will come back. We will also get the 980 // onServiceDisconnected, which has all the cleanup code. So let that do 981 // it. 982 Log.w(TAG, "RemoteException during connect for " + mServiceComponent); 983 if (DBG) { 984 Log.d(TAG, "ServiceCallbacks.onConnect..."); 985 dump(); 986 } 987 } 988 } 989 }); 990 } 991 992 @Override 993 public void onServiceDisconnected(final ComponentName name) { 994 postOrRun(new Runnable() { 995 @Override 996 public void run() { 997 if (DBG) { 998 Log.d(TAG, "MediaServiceConnection.onServiceDisconnected name=" + name 999 + " this=" + this + " mServiceConnection=" + mServiceConnection); 1000 dump(); 1001 } 1002 1003 // Make sure we are still the current connection, and that they haven't called 1004 // disconnect(). 1005 if (!isCurrent("onServiceDisconnected")) { 1006 return; 1007 } 1008 1009 // Clear out what we set in onServiceConnected 1010 mServiceBinder = null; 1011 mServiceCallbacks = null; 1012 1013 // And tell the app that it's suspended. 1014 mState = CONNECT_STATE_SUSPENDED; 1015 mCallback.onConnectionSuspended(); 1016 } 1017 }); 1018 } 1019 1020 private void postOrRun(Runnable r) { 1021 if (Thread.currentThread() == mHandler.getLooper().getThread()) { 1022 r.run(); 1023 } else { 1024 mHandler.post(r); 1025 } 1026 } 1027 1028 /** 1029 * Return true if this is the current ServiceConnection. Also logs if it's not. 1030 */ 1031 private boolean isCurrent(String funcName) { 1032 if (mServiceConnection != this) { 1033 if (mState != CONNECT_STATE_DISCONNECTED) { 1034 // Check mState, because otherwise this log is noisy. 1035 Log.i(TAG, funcName + " for " + mServiceComponent + " with mServiceConnection=" 1036 + mServiceConnection + " this=" + this); 1037 } 1038 return false; 1039 } 1040 return true; 1041 } 1042 } 1043 1044 /** 1045 * Callbacks from the service. 1046 */ 1047 private static class ServiceCallbacks extends IMediaBrowserServiceCallbacks.Stub { 1048 private WeakReference<MediaBrowser> mMediaBrowser; 1049 1050 public ServiceCallbacks(MediaBrowser mediaBrowser) { 1051 mMediaBrowser = new WeakReference<MediaBrowser>(mediaBrowser); 1052 } 1053 1054 /** 1055 * The other side has acknowledged our connection. The parameters to this function 1056 * are the initial data as requested. 1057 */ 1058 @Override 1059 public void onConnect(String root, MediaSession.Token session, 1060 final Bundle extras) { 1061 MediaBrowser mediaBrowser = mMediaBrowser.get(); 1062 if (mediaBrowser != null) { 1063 mediaBrowser.onServiceConnected(this, root, session, extras); 1064 } 1065 } 1066 1067 /** 1068 * The other side does not like us. Tell the app via onConnectionFailed. 1069 */ 1070 @Override 1071 public void onConnectFailed() { 1072 MediaBrowser mediaBrowser = mMediaBrowser.get(); 1073 if (mediaBrowser != null) { 1074 mediaBrowser.onConnectionFailed(this); 1075 } 1076 } 1077 1078 @Override 1079 public void onLoadChildren(String parentId, ParceledListSlice list) { 1080 onLoadChildrenWithOptions(parentId, list, null); 1081 } 1082 1083 @Override 1084 public void onLoadChildrenWithOptions(String parentId, ParceledListSlice list, 1085 final Bundle options) { 1086 MediaBrowser mediaBrowser = mMediaBrowser.get(); 1087 if (mediaBrowser != null) { 1088 mediaBrowser.onLoadChildren(this, parentId, list, options); 1089 } 1090 } 1091 } 1092 1093 private static class Subscription { 1094 private final List<SubscriptionCallback> mCallbacks; 1095 private final List<Bundle> mOptionsList; 1096 1097 public Subscription() { 1098 mCallbacks = new ArrayList<>(); 1099 mOptionsList = new ArrayList<>(); 1100 } 1101 1102 public boolean isEmpty() { 1103 return mCallbacks.isEmpty(); 1104 } 1105 1106 public List<Bundle> getOptionsList() { 1107 return mOptionsList; 1108 } 1109 1110 public List<SubscriptionCallback> getCallbacks() { 1111 return mCallbacks; 1112 } 1113 1114 public SubscriptionCallback getCallback(Bundle options) { 1115 for (int i = 0; i < mOptionsList.size(); ++i) { 1116 if (MediaBrowserUtils.areSameOptions(mOptionsList.get(i), options)) { 1117 return mCallbacks.get(i); 1118 } 1119 } 1120 return null; 1121 } 1122 1123 public void putCallback(Bundle options, SubscriptionCallback callback) { 1124 for (int i = 0; i < mOptionsList.size(); ++i) { 1125 if (MediaBrowserUtils.areSameOptions(mOptionsList.get(i), options)) { 1126 mCallbacks.set(i, callback); 1127 return; 1128 } 1129 } 1130 mCallbacks.add(callback); 1131 mOptionsList.add(options); 1132 } 1133 } 1134} 1135