DocumentsContract.java revision d2e1e810a79ce0988df57c0bcbcd184e14a067b4
1/* 2 * Copyright (C) 2013 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.provider; 18 19import static android.net.TrafficStats.KB_IN_BYTES; 20import static libcore.io.OsConstants.SEEK_SET; 21 22import android.content.ContentProviderClient; 23import android.content.ContentResolver; 24import android.content.Context; 25import android.content.Intent; 26import android.content.pm.ResolveInfo; 27import android.content.res.AssetFileDescriptor; 28import android.database.Cursor; 29import android.graphics.Bitmap; 30import android.graphics.BitmapFactory; 31import android.graphics.Point; 32import android.net.Uri; 33import android.os.Bundle; 34import android.os.CancellationSignal; 35import android.os.ParcelFileDescriptor; 36import android.os.ParcelFileDescriptor.OnCloseListener; 37import android.os.RemoteException; 38import android.util.Log; 39 40import libcore.io.ErrnoException; 41import libcore.io.IoUtils; 42import libcore.io.Libcore; 43 44import java.io.BufferedInputStream; 45import java.io.FileDescriptor; 46import java.io.FileInputStream; 47import java.io.IOException; 48import java.util.List; 49 50/** 51 * Defines the contract between a documents provider and the platform. 52 * <p> 53 * To create a document provider, extend {@link DocumentsProvider}, which 54 * provides a foundational implementation of this contract. 55 * 56 * @see DocumentsProvider 57 */ 58public final class DocumentsContract { 59 private static final String TAG = "Documents"; 60 61 // content://com.example/root/ 62 // content://com.example/root/sdcard/ 63 // content://com.example/root/sdcard/recent/ 64 // content://com.example/root/sdcard/search/?query=pony 65 // content://com.example/document/12/ 66 // content://com.example/document/12/children/ 67 68 private DocumentsContract() { 69 } 70 71 /** 72 * Intent action used to identify {@link DocumentsProvider} instances. 73 */ 74 public static final String PROVIDER_INTERFACE = "android.content.action.DOCUMENTS_PROVIDER"; 75 76 /** {@hide} */ 77 public static final String ACTION_MANAGE_ROOT = "android.provider.action.MANAGE_ROOT"; 78 /** {@hide} */ 79 public static final String ACTION_MANAGE_DOCUMENT = "android.provider.action.MANAGE_DOCUMENT"; 80 81 /** 82 * Buffer is large enough to rewind past any EXIF headers. 83 */ 84 private static final int THUMBNAIL_BUFFER_SIZE = (int) (128 * KB_IN_BYTES); 85 86 /** 87 * Constants related to a document, including {@link Cursor} columns names 88 * and flags. 89 * <p> 90 * A document can be either an openable file (with a specific MIME type), or 91 * a directory containing additional documents (with the 92 * {@link #MIME_TYPE_DIR} MIME type). 93 * <p> 94 * All columns are <em>read-only</em> to client applications. 95 */ 96 public final static class Document { 97 private Document() { 98 } 99 100 /** 101 * Unique ID of a document. This ID is both provided by and interpreted 102 * by a {@link DocumentsProvider}, and should be treated as an opaque 103 * value by client applications. This column is required. 104 * <p> 105 * Each document must have a unique ID within a provider, but that 106 * single document may be included as a child of multiple directories. 107 * <p> 108 * A provider must always return durable IDs, since they will be used to 109 * issue long-term Uri permission grants when an application interacts 110 * with {@link Intent#ACTION_OPEN_DOCUMENT} and 111 * {@link Intent#ACTION_CREATE_DOCUMENT}. 112 * <p> 113 * Type: STRING 114 */ 115 public static final String COLUMN_DOCUMENT_ID = "document_id"; 116 117 /** 118 * Concrete MIME type of a document. For example, "image/png" or 119 * "application/pdf" for openable files. A document can also be a 120 * directory containing additional documents, which is represented with 121 * the {@link #MIME_TYPE_DIR} MIME type. This column is required. 122 * <p> 123 * Type: STRING 124 * 125 * @see #MIME_TYPE_DIR 126 */ 127 public static final String COLUMN_MIME_TYPE = "mime_type"; 128 129 /** 130 * Display name of a document, used as the primary title displayed to a 131 * user. This column is required. 132 * <p> 133 * Type: STRING 134 */ 135 public static final String COLUMN_DISPLAY_NAME = OpenableColumns.DISPLAY_NAME; 136 137 /** 138 * Summary of a document, which may be shown to a user. This column is 139 * optional, and may be {@code null}. 140 * <p> 141 * Type: STRING 142 */ 143 public static final String COLUMN_SUMMARY = "summary"; 144 145 /** 146 * Timestamp when a document was last modified, in milliseconds since 147 * January 1, 1970 00:00:00.0 UTC. This column is required, and may be 148 * {@code null} if unknown. A {@link DocumentsProvider} can update this 149 * field using events from {@link OnCloseListener} or other reliable 150 * {@link ParcelFileDescriptor} transports. 151 * <p> 152 * Type: INTEGER (long) 153 * 154 * @see System#currentTimeMillis() 155 */ 156 public static final String COLUMN_LAST_MODIFIED = "last_modified"; 157 158 /** 159 * Specific icon resource ID for a document. This column is optional, 160 * and may be {@code null} to use a platform-provided default icon based 161 * on {@link #COLUMN_MIME_TYPE}. 162 * <p> 163 * Type: INTEGER (int) 164 */ 165 public static final String COLUMN_ICON = "icon"; 166 167 /** 168 * Flags that apply to a document. This column is required. 169 * <p> 170 * Type: INTEGER (int) 171 * 172 * @see #FLAG_SUPPORTS_WRITE 173 * @see #FLAG_SUPPORTS_DELETE 174 * @see #FLAG_SUPPORTS_THUMBNAIL 175 * @see #FLAG_DIR_PREFERS_GRID 176 * @see #FLAG_DIR_PREFERS_LAST_MODIFIED 177 */ 178 public static final String COLUMN_FLAGS = "flags"; 179 180 /** 181 * Size of a document, in bytes, or {@code null} if unknown. This column 182 * is required. 183 * <p> 184 * Type: INTEGER (long) 185 */ 186 public static final String COLUMN_SIZE = OpenableColumns.SIZE; 187 188 /** 189 * MIME type of a document which is a directory that may contain 190 * additional documents. 191 * 192 * @see #COLUMN_MIME_TYPE 193 */ 194 public static final String MIME_TYPE_DIR = "vnd.android.document/directory"; 195 196 /** 197 * Flag indicating that a document can be represented as a thumbnail. 198 * 199 * @see #COLUMN_FLAGS 200 * @see DocumentsContract#getDocumentThumbnail(ContentResolver, Uri, 201 * Point, CancellationSignal) 202 * @see DocumentsProvider#openDocumentThumbnail(String, Point, 203 * android.os.CancellationSignal) 204 */ 205 public static final int FLAG_SUPPORTS_THUMBNAIL = 1; 206 207 /** 208 * Flag indicating that a document supports writing. 209 * <p> 210 * When a document is opened with {@link Intent#ACTION_OPEN_DOCUMENT}, 211 * the calling application is granted both 212 * {@link Intent#FLAG_GRANT_READ_URI_PERMISSION} and 213 * {@link Intent#FLAG_GRANT_WRITE_URI_PERMISSION}. However, the actual 214 * writability of a document may change over time, for example due to 215 * remote access changes. This flag indicates that a document client can 216 * expect {@link ContentResolver#openOutputStream(Uri)} to succeed. 217 * 218 * @see #COLUMN_FLAGS 219 */ 220 public static final int FLAG_SUPPORTS_WRITE = 1 << 1; 221 222 /** 223 * Flag indicating that a document is deletable. 224 * 225 * @see #COLUMN_FLAGS 226 * @see DocumentsContract#deleteDocument(ContentResolver, Uri) 227 * @see DocumentsProvider#deleteDocument(String) 228 */ 229 public static final int FLAG_SUPPORTS_DELETE = 1 << 2; 230 231 /** 232 * Flag indicating that a document is a directory that supports creation 233 * of new files within it. Only valid when {@link #COLUMN_MIME_TYPE} is 234 * {@link #MIME_TYPE_DIR}. 235 * 236 * @see #COLUMN_FLAGS 237 * @see DocumentsContract#createDocument(ContentResolver, Uri, String, 238 * String) 239 * @see DocumentsProvider#createDocument(String, String, String) 240 */ 241 public static final int FLAG_DIR_SUPPORTS_CREATE = 1 << 3; 242 243 /** 244 * Flag indicating that a directory prefers its contents be shown in a 245 * larger format grid. Usually suitable when a directory contains mostly 246 * pictures. Only valid when {@link #COLUMN_MIME_TYPE} is 247 * {@link #MIME_TYPE_DIR}. 248 * 249 * @see #COLUMN_FLAGS 250 */ 251 public static final int FLAG_DIR_PREFERS_GRID = 1 << 4; 252 253 /** 254 * Flag indicating that a directory prefers its contents be sorted by 255 * {@link #COLUMN_LAST_MODIFIED}. Only valid when 256 * {@link #COLUMN_MIME_TYPE} is {@link #MIME_TYPE_DIR}. 257 * 258 * @see #COLUMN_FLAGS 259 */ 260 public static final int FLAG_DIR_PREFERS_LAST_MODIFIED = 1 << 5; 261 262 /** 263 * Flag indicating that document titles should be hidden when viewing 264 * this directory in a larger format grid. For example, a directory 265 * containing only images may want the image thumbnails to speak for 266 * themselves. Only valid when {@link #COLUMN_MIME_TYPE} is 267 * {@link #MIME_TYPE_DIR}. 268 * 269 * @see #COLUMN_FLAGS 270 * @see #FLAG_DIR_PREFERS_GRID 271 * @hide 272 */ 273 public static final int FLAG_DIR_HIDE_GRID_TITLES = 1 << 16; 274 } 275 276 /** 277 * Constants related to a root of documents, including {@link Cursor} 278 * columns names and flags. 279 * <p> 280 * All columns are <em>read-only</em> to client applications. 281 */ 282 public final static class Root { 283 private Root() { 284 } 285 286 /** 287 * Unique ID of a root. This ID is both provided by and interpreted by a 288 * {@link DocumentsProvider}, and should be treated as an opaque value 289 * by client applications. This column is required. 290 * <p> 291 * Type: STRING 292 */ 293 public static final String COLUMN_ROOT_ID = "root_id"; 294 295 /** 296 * Flags that apply to a root. This column is required. 297 * <p> 298 * Type: INTEGER (int) 299 * 300 * @see #FLAG_LOCAL_ONLY 301 * @see #FLAG_SUPPORTS_CREATE 302 * @see #FLAG_SUPPORTS_RECENTS 303 * @see #FLAG_SUPPORTS_SEARCH 304 */ 305 public static final String COLUMN_FLAGS = "flags"; 306 307 /** 308 * Icon resource ID for a root. This column is required. 309 * <p> 310 * Type: INTEGER (int) 311 */ 312 public static final String COLUMN_ICON = "icon"; 313 314 /** 315 * Title for a root, which will be shown to a user. This column is 316 * required. 317 * <p> 318 * Type: STRING 319 */ 320 public static final String COLUMN_TITLE = "title"; 321 322 /** 323 * Summary for this root, which may be shown to a user. This column is 324 * optional, and may be {@code null}. 325 * <p> 326 * Type: STRING 327 */ 328 public static final String COLUMN_SUMMARY = "summary"; 329 330 /** 331 * Document which is a directory that represents the top directory of 332 * this root. This column is required. 333 * <p> 334 * Type: STRING 335 * 336 * @see Document#COLUMN_DOCUMENT_ID 337 */ 338 public static final String COLUMN_DOCUMENT_ID = "document_id"; 339 340 /** 341 * Number of bytes available in this root. This column is optional, and 342 * may be {@code null} if unknown or unbounded. 343 * <p> 344 * Type: INTEGER (long) 345 */ 346 public static final String COLUMN_AVAILABLE_BYTES = "available_bytes"; 347 348 /** 349 * MIME types supported by this root. This column is optional, and if 350 * {@code null} the root is assumed to support all MIME types. Multiple 351 * MIME types can be separated by a newline. For example, a root 352 * supporting audio might return "audio/*\napplication/x-flac". 353 * <p> 354 * Type: STRING 355 */ 356 public static final String COLUMN_MIME_TYPES = "mime_types"; 357 358 /** {@hide} */ 359 public static final String MIME_TYPE_ITEM = "vnd.android.document/root"; 360 361 /** 362 * Flag indicating that at least one directory under this root supports 363 * creating content. Roots with this flag will be shown when an 364 * application interacts with {@link Intent#ACTION_CREATE_DOCUMENT}. 365 * 366 * @see #COLUMN_FLAGS 367 */ 368 public static final int FLAG_SUPPORTS_CREATE = 1; 369 370 /** 371 * Flag indicating that this root offers content that is strictly local 372 * on the device. That is, no network requests are made for the content. 373 * 374 * @see #COLUMN_FLAGS 375 * @see Intent#EXTRA_LOCAL_ONLY 376 */ 377 public static final int FLAG_LOCAL_ONLY = 1 << 1; 378 379 /** 380 * Flag indicating that this root can report recently modified 381 * documents. 382 * 383 * @see #COLUMN_FLAGS 384 * @see DocumentsContract#buildRecentDocumentsUri(String, String) 385 */ 386 public static final int FLAG_SUPPORTS_RECENTS = 1 << 2; 387 388 /** 389 * Flag indicating that this root supports search. 390 * 391 * @see #COLUMN_FLAGS 392 * @see DocumentsProvider#querySearchDocuments(String, String, 393 * String[]) 394 */ 395 public static final int FLAG_SUPPORTS_SEARCH = 1 << 3; 396 397 /** 398 * Flag indicating that this root is currently empty. This may be used 399 * to hide the root when opening documents, but the root will still be 400 * shown when creating documents and {@link #FLAG_SUPPORTS_CREATE} is 401 * also set. If the value of this flag changes, such as when a root 402 * becomes non-empty, you must send a content changed notification for 403 * {@link DocumentsContract#buildRootsUri(String)}. 404 * 405 * @see #COLUMN_FLAGS 406 * @see ContentResolver#notifyChange(Uri, 407 * android.database.ContentObserver, boolean) 408 * @hide 409 */ 410 public static final int FLAG_EMPTY = 1 << 16; 411 412 /** 413 * Flag indicating that this root should only be visible to advanced 414 * users. 415 * 416 * @see #COLUMN_FLAGS 417 * @hide 418 */ 419 public static final int FLAG_ADVANCED = 1 << 17; 420 } 421 422 /** 423 * Optional boolean flag included in a directory {@link Cursor#getExtras()} 424 * indicating that a document provider is still loading data. For example, a 425 * provider has returned some results, but is still waiting on an 426 * outstanding network request. The provider must send a content changed 427 * notification when loading is finished. 428 * 429 * @see ContentResolver#notifyChange(Uri, android.database.ContentObserver, 430 * boolean) 431 */ 432 public static final String EXTRA_LOADING = "loading"; 433 434 /** 435 * Optional string included in a directory {@link Cursor#getExtras()} 436 * providing an informational message that should be shown to a user. For 437 * example, a provider may wish to indicate that not all documents are 438 * available. 439 */ 440 public static final String EXTRA_INFO = "info"; 441 442 /** 443 * Optional string included in a directory {@link Cursor#getExtras()} 444 * providing an error message that should be shown to a user. For example, a 445 * provider may wish to indicate that a network error occurred. The user may 446 * choose to retry, resulting in a new query. 447 */ 448 public static final String EXTRA_ERROR = "error"; 449 450 /** {@hide} */ 451 public static final String METHOD_CREATE_DOCUMENT = "android:createDocument"; 452 /** {@hide} */ 453 public static final String METHOD_DELETE_DOCUMENT = "android:deleteDocument"; 454 455 /** {@hide} */ 456 public static final String EXTRA_THUMBNAIL_SIZE = "thumbnail_size"; 457 458 private static final String PATH_ROOT = "root"; 459 private static final String PATH_RECENT = "recent"; 460 private static final String PATH_DOCUMENT = "document"; 461 private static final String PATH_CHILDREN = "children"; 462 private static final String PATH_SEARCH = "search"; 463 464 private static final String PARAM_QUERY = "query"; 465 private static final String PARAM_MANAGE = "manage"; 466 467 /** 468 * Build Uri representing the roots of a document provider. When queried, a 469 * provider will return one or more rows with columns defined by 470 * {@link Root}. 471 * 472 * @see DocumentsProvider#queryRoots(String[]) 473 */ 474 public static Uri buildRootsUri(String authority) { 475 return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT) 476 .authority(authority).appendPath(PATH_ROOT).build(); 477 } 478 479 /** 480 * Build Uri representing the given {@link Root#COLUMN_ROOT_ID} in a 481 * document provider. 482 * 483 * @see #getRootId(Uri) 484 */ 485 public static Uri buildRootUri(String authority, String rootId) { 486 return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT) 487 .authority(authority).appendPath(PATH_ROOT).appendPath(rootId).build(); 488 } 489 490 /** 491 * Build Uri representing the recently modified documents of a specific root 492 * in a document provider. When queried, a provider will return zero or more 493 * rows with columns defined by {@link Document}. 494 * 495 * @see DocumentsProvider#queryRecentDocuments(String, String[]) 496 * @see #getRootId(Uri) 497 */ 498 public static Uri buildRecentDocumentsUri(String authority, String rootId) { 499 return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT) 500 .authority(authority).appendPath(PATH_ROOT).appendPath(rootId) 501 .appendPath(PATH_RECENT).build(); 502 } 503 504 /** 505 * Build Uri representing the given {@link Document#COLUMN_DOCUMENT_ID} in a 506 * document provider. When queried, a provider will return a single row with 507 * columns defined by {@link Document}. 508 * 509 * @see DocumentsProvider#queryDocument(String, String[]) 510 * @see #getDocumentId(Uri) 511 */ 512 public static Uri buildDocumentUri(String authority, String documentId) { 513 return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT) 514 .authority(authority).appendPath(PATH_DOCUMENT).appendPath(documentId).build(); 515 } 516 517 /** 518 * Build Uri representing the children of the given directory in a document 519 * provider. When queried, a provider will return zero or more rows with 520 * columns defined by {@link Document}. 521 * 522 * @param parentDocumentId the document to return children for, which must 523 * be a directory with MIME type of 524 * {@link Document#MIME_TYPE_DIR}. 525 * @see DocumentsProvider#queryChildDocuments(String, String[], String) 526 * @see #getDocumentId(Uri) 527 */ 528 public static Uri buildChildDocumentsUri(String authority, String parentDocumentId) { 529 return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT).authority(authority) 530 .appendPath(PATH_DOCUMENT).appendPath(parentDocumentId).appendPath(PATH_CHILDREN) 531 .build(); 532 } 533 534 /** 535 * Build Uri representing a search for matching documents under a specific 536 * root in a document provider. When queried, a provider will return zero or 537 * more rows with columns defined by {@link Document}. 538 * 539 * @see DocumentsProvider#querySearchDocuments(String, String, String[]) 540 * @see #getRootId(Uri) 541 * @see #getSearchDocumentsQuery(Uri) 542 */ 543 public static Uri buildSearchDocumentsUri( 544 String authority, String rootId, String query) { 545 return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT).authority(authority) 546 .appendPath(PATH_ROOT).appendPath(rootId).appendPath(PATH_SEARCH) 547 .appendQueryParameter(PARAM_QUERY, query).build(); 548 } 549 550 /** 551 * Test if the given Uri represents a {@link Document} backed by a 552 * {@link DocumentsProvider}. 553 */ 554 public static boolean isDocumentUri(Context context, Uri uri) { 555 final List<String> paths = uri.getPathSegments(); 556 if (paths.size() < 2) { 557 return false; 558 } 559 if (!PATH_DOCUMENT.equals(paths.get(0))) { 560 return false; 561 } 562 563 final Intent intent = new Intent(PROVIDER_INTERFACE); 564 final List<ResolveInfo> infos = context.getPackageManager() 565 .queryIntentContentProviders(intent, 0); 566 for (ResolveInfo info : infos) { 567 if (uri.getAuthority().equals(info.providerInfo.authority)) { 568 return true; 569 } 570 } 571 return false; 572 } 573 574 /** 575 * Extract the {@link Root#COLUMN_ROOT_ID} from the given Uri. 576 */ 577 public static String getRootId(Uri rootUri) { 578 final List<String> paths = rootUri.getPathSegments(); 579 if (paths.size() < 2) { 580 throw new IllegalArgumentException("Not a root: " + rootUri); 581 } 582 if (!PATH_ROOT.equals(paths.get(0))) { 583 throw new IllegalArgumentException("Not a root: " + rootUri); 584 } 585 return paths.get(1); 586 } 587 588 /** 589 * Extract the {@link Document#COLUMN_DOCUMENT_ID} from the given Uri. 590 */ 591 public static String getDocumentId(Uri documentUri) { 592 final List<String> paths = documentUri.getPathSegments(); 593 if (paths.size() < 2) { 594 throw new IllegalArgumentException("Not a document: " + documentUri); 595 } 596 if (!PATH_DOCUMENT.equals(paths.get(0))) { 597 throw new IllegalArgumentException("Not a document: " + documentUri); 598 } 599 return paths.get(1); 600 } 601 602 /** 603 * Extract the search query from a Uri built by 604 * {@link #buildSearchDocumentsUri(String, String, String)}. 605 */ 606 public static String getSearchDocumentsQuery(Uri searchDocumentsUri) { 607 return searchDocumentsUri.getQueryParameter(PARAM_QUERY); 608 } 609 610 /** {@hide} */ 611 public static Uri setManageMode(Uri uri) { 612 return uri.buildUpon().appendQueryParameter(PARAM_MANAGE, "true").build(); 613 } 614 615 /** {@hide} */ 616 public static boolean isManageMode(Uri uri) { 617 return uri.getBooleanQueryParameter(PARAM_MANAGE, false); 618 } 619 620 /** 621 * Return thumbnail representing the document at the given Uri. Callers are 622 * responsible for their own in-memory caching. 623 * 624 * @param documentUri document to return thumbnail for, which must have 625 * {@link Document#FLAG_SUPPORTS_THUMBNAIL} set. 626 * @param size optimal thumbnail size desired. A provider may return a 627 * thumbnail of a different size, but never more than double the 628 * requested size. 629 * @param signal signal used to indicate that caller is no longer interested 630 * in the thumbnail. 631 * @return decoded thumbnail, or {@code null} if problem was encountered. 632 * @see DocumentsProvider#openDocumentThumbnail(String, Point, 633 * android.os.CancellationSignal) 634 */ 635 public static Bitmap getDocumentThumbnail( 636 ContentResolver resolver, Uri documentUri, Point size, CancellationSignal signal) { 637 final ContentProviderClient client = resolver.acquireUnstableContentProviderClient( 638 documentUri.getAuthority()); 639 try { 640 return getDocumentThumbnail(client, documentUri, size, signal); 641 } catch (Exception e) { 642 Log.w(TAG, "Failed to load thumbnail for " + documentUri + ": " + e); 643 return null; 644 } finally { 645 ContentProviderClient.releaseQuietly(client); 646 } 647 } 648 649 /** {@hide} */ 650 public static Bitmap getDocumentThumbnail( 651 ContentProviderClient client, Uri documentUri, Point size, CancellationSignal signal) 652 throws RemoteException, IOException { 653 final Bundle openOpts = new Bundle(); 654 openOpts.putParcelable(DocumentsContract.EXTRA_THUMBNAIL_SIZE, size); 655 656 AssetFileDescriptor afd = null; 657 try { 658 afd = client.openTypedAssetFileDescriptor(documentUri, "image/*", openOpts, signal); 659 660 final FileDescriptor fd = afd.getFileDescriptor(); 661 final long offset = afd.getStartOffset(); 662 663 // Try seeking on the returned FD, since it gives us the most 664 // optimal decode path; otherwise fall back to buffering. 665 BufferedInputStream is = null; 666 try { 667 Libcore.os.lseek(fd, offset, SEEK_SET); 668 } catch (ErrnoException e) { 669 is = new BufferedInputStream(new FileInputStream(fd), THUMBNAIL_BUFFER_SIZE); 670 is.mark(THUMBNAIL_BUFFER_SIZE); 671 } 672 673 // We requested a rough thumbnail size, but the remote size may have 674 // returned something giant, so defensively scale down as needed. 675 final BitmapFactory.Options opts = new BitmapFactory.Options(); 676 opts.inJustDecodeBounds = true; 677 if (is != null) { 678 BitmapFactory.decodeStream(is, null, opts); 679 } else { 680 BitmapFactory.decodeFileDescriptor(fd, null, opts); 681 } 682 683 final int widthSample = opts.outWidth / size.x; 684 final int heightSample = opts.outHeight / size.y; 685 686 opts.inJustDecodeBounds = false; 687 opts.inSampleSize = Math.min(widthSample, heightSample); 688 Log.d(TAG, "Decoding with sample size " + opts.inSampleSize); 689 if (is != null) { 690 is.reset(); 691 return BitmapFactory.decodeStream(is, null, opts); 692 } else { 693 try { 694 Libcore.os.lseek(fd, offset, SEEK_SET); 695 } catch (ErrnoException e) { 696 e.rethrowAsIOException(); 697 } 698 return BitmapFactory.decodeFileDescriptor(fd, null, opts); 699 } 700 } finally { 701 IoUtils.closeQuietly(afd); 702 } 703 } 704 705 /** 706 * Create a new document with given MIME type and display name. 707 * 708 * @param parentDocumentUri directory with 709 * {@link Document#FLAG_DIR_SUPPORTS_CREATE} 710 * @param mimeType MIME type of new document 711 * @param displayName name of new document 712 * @return newly created document, or {@code null} if failed 713 * @hide 714 */ 715 public static Uri createDocument(ContentResolver resolver, Uri parentDocumentUri, 716 String mimeType, String displayName) { 717 final ContentProviderClient client = resolver.acquireUnstableContentProviderClient( 718 parentDocumentUri.getAuthority()); 719 try { 720 return createDocument(client, parentDocumentUri, mimeType, displayName); 721 } catch (Exception e) { 722 Log.w(TAG, "Failed to create document", e); 723 return null; 724 } finally { 725 ContentProviderClient.releaseQuietly(client); 726 } 727 } 728 729 /** {@hide} */ 730 public static Uri createDocument(ContentProviderClient client, Uri parentDocumentUri, 731 String mimeType, String displayName) throws RemoteException { 732 final Bundle in = new Bundle(); 733 in.putString(Document.COLUMN_DOCUMENT_ID, getDocumentId(parentDocumentUri)); 734 in.putString(Document.COLUMN_MIME_TYPE, mimeType); 735 in.putString(Document.COLUMN_DISPLAY_NAME, displayName); 736 737 final Bundle out = client.call(METHOD_CREATE_DOCUMENT, null, in); 738 return buildDocumentUri( 739 parentDocumentUri.getAuthority(), out.getString(Document.COLUMN_DOCUMENT_ID)); 740 } 741 742 /** 743 * Delete the given document. 744 * 745 * @param documentUri document with {@link Document#FLAG_SUPPORTS_DELETE} 746 * @return if the document was deleted successfully. 747 */ 748 public static boolean deleteDocument(ContentResolver resolver, Uri documentUri) { 749 final ContentProviderClient client = resolver.acquireUnstableContentProviderClient( 750 documentUri.getAuthority()); 751 try { 752 deleteDocument(client, documentUri); 753 return true; 754 } catch (Exception e) { 755 Log.w(TAG, "Failed to delete document", e); 756 return false; 757 } finally { 758 ContentProviderClient.releaseQuietly(client); 759 } 760 } 761 762 /** {@hide} */ 763 public static void deleteDocument(ContentProviderClient client, Uri documentUri) 764 throws RemoteException { 765 final Bundle in = new Bundle(); 766 in.putString(Document.COLUMN_DOCUMENT_ID, getDocumentId(documentUri)); 767 768 client.call(METHOD_DELETE_DOCUMENT, null, in); 769 } 770} 771