LocalAlbumSet.java revision d134e18e3c2d9614099d3b74e1a6a12159a1e81a
1/* 2 * Copyright (C) 2010 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 com.android.gallery3d.data; 18 19import android.content.ContentResolver; 20import android.database.Cursor; 21import android.net.Uri; 22import android.provider.MediaStore.Files; 23import android.provider.MediaStore.Files.FileColumns; 24import android.provider.MediaStore.Images; 25import android.provider.MediaStore.Images.ImageColumns; 26import android.provider.MediaStore.Video; 27import android.util.Log; 28 29import com.android.gallery3d.R; 30import com.android.gallery3d.app.GalleryApp; 31import com.android.gallery3d.common.Utils; 32import com.android.gallery3d.util.Future; 33import com.android.gallery3d.util.FutureListener; 34import com.android.gallery3d.util.MediaSetUtils; 35import com.android.gallery3d.util.ThreadPool; 36import com.android.gallery3d.util.ThreadPool.JobContext; 37 38import java.util.ArrayList; 39import java.util.Comparator; 40 41// LocalAlbumSet lists all image or video albums in the local storage. 42// The path should be "/local/image", "local/video" or "/local/all" 43public class LocalAlbumSet extends MediaSet 44 implements FutureListener<ArrayList<MediaSet>> { 45 public static final Path PATH_ALL = Path.fromString("/local/all"); 46 public static final Path PATH_IMAGE = Path.fromString("/local/image"); 47 public static final Path PATH_VIDEO = Path.fromString("/local/video"); 48 49 private static final String TAG = "LocalAlbumSet"; 50 private static final String EXTERNAL_MEDIA = "external"; 51 52 // The indices should match the following projections. 53 private static final int INDEX_BUCKET_ID = 0; 54 private static final int INDEX_MEDIA_TYPE = 1; 55 private static final int INDEX_BUCKET_NAME = 2; 56 57 private static final Uri mBaseUri = Files.getContentUri(EXTERNAL_MEDIA); 58 private static final Uri mWatchUriImage = Images.Media.EXTERNAL_CONTENT_URI; 59 private static final Uri mWatchUriVideo = Video.Media.EXTERNAL_CONTENT_URI; 60 61 // BUCKET_DISPLAY_NAME is a string like "Camera" which is the directory 62 // name of where an image or video is in. BUCKET_ID is a hash of the path 63 // name of that directory (see computeBucketValues() in MediaProvider for 64 // details). MEDIA_TYPE is video, image, audio, etc. 65 // 66 // The "albums" are not explicitly recorded in the database, but each image 67 // or video has the two columns (BUCKET_ID, MEDIA_TYPE). We define an 68 // "album" to be the collection of images/videos which have the same value 69 // for the two columns. 70 // 71 // The goal of the query (used in loadSubMediaSets()) is to find all albums, 72 // that is, all unique values for (BUCKET_ID, MEDIA_TYPE). In the meantime 73 // sort them by the timestamp of the latest image/video in each of the album. 74 // 75 // The order of columns below is important: it must match to the index in 76 // MediaStore. 77 private static final String[] PROJECTION_BUCKET = { 78 ImageColumns.BUCKET_ID, 79 FileColumns.MEDIA_TYPE, 80 ImageColumns.BUCKET_DISPLAY_NAME }; 81 82 // We want to order the albums by reverse chronological order. We abuse the 83 // "WHERE" parameter to insert a "GROUP BY" clause into the SQL statement. 84 // The template for "WHERE" parameter is like: 85 // SELECT ... FROM ... WHERE (%s) 86 // and we make it look like: 87 // SELECT ... FROM ... WHERE (1) GROUP BY 1,(2) 88 // The "(1)" means true. The "1,(2)" means the first two columns specified 89 // after SELECT. Note that because there is a ")" in the template, we use 90 // "(2" to match it. 91 private static final String BUCKET_GROUP_BY = 92 "1) GROUP BY 1,(2"; 93 private static final String BUCKET_ORDER_BY = "MAX(datetaken) DESC"; 94 95 private final GalleryApp mApplication; 96 private final int mType; 97 private ArrayList<MediaSet> mAlbums = new ArrayList<MediaSet>(); 98 private final ChangeNotifier mNotifierImage; 99 private final ChangeNotifier mNotifierVideo; 100 private final String mName; 101 private Future<ArrayList<MediaSet>> mLoadTask; 102 private ArrayList<MediaSet> mLoadBuffer; 103 104 public LocalAlbumSet(Path path, GalleryApp application) { 105 super(path, nextVersionNumber()); 106 mApplication = application; 107 mType = getTypeFromPath(path); 108 mNotifierImage = new ChangeNotifier(this, mWatchUriImage, application); 109 mNotifierVideo = new ChangeNotifier(this, mWatchUriVideo, application); 110 mName = application.getResources().getString( 111 R.string.set_label_local_albums); 112 } 113 114 private static int getTypeFromPath(Path path) { 115 String name[] = path.split(); 116 if (name.length < 2) { 117 throw new IllegalArgumentException(path.toString()); 118 } 119 return getTypeFromString(name[1]); 120 } 121 122 @Override 123 public MediaSet getSubMediaSet(int index) { 124 return mAlbums.get(index); 125 } 126 127 @Override 128 public int getSubMediaSetCount() { 129 return mAlbums.size(); 130 } 131 132 @Override 133 public String getName() { 134 return mName; 135 } 136 137 private BucketEntry[] loadBucketEntries(JobContext jc) { 138 Uri uri = mBaseUri; 139 140 Log.v("DebugLoadingTime", "start quering media provider"); 141 Cursor cursor = mApplication.getContentResolver().query( 142 uri, PROJECTION_BUCKET, BUCKET_GROUP_BY, null, BUCKET_ORDER_BY); 143 if (cursor == null) { 144 Log.w(TAG, "cannot open local database: " + uri); 145 return new BucketEntry[0]; 146 } 147 ArrayList<BucketEntry> buffer = new ArrayList<BucketEntry>(); 148 int typeBits = 0; 149 if ((mType & MEDIA_TYPE_IMAGE) != 0) { 150 typeBits |= (1 << FileColumns.MEDIA_TYPE_IMAGE); 151 } 152 if ((mType & MEDIA_TYPE_VIDEO) != 0) { 153 typeBits |= (1 << FileColumns.MEDIA_TYPE_VIDEO); 154 } 155 try { 156 while (cursor.moveToNext()) { 157 if ((typeBits & (1 << cursor.getInt(INDEX_MEDIA_TYPE))) != 0) { 158 BucketEntry entry = new BucketEntry( 159 cursor.getInt(INDEX_BUCKET_ID), 160 cursor.getString(INDEX_BUCKET_NAME)); 161 if (!buffer.contains(entry)) { 162 buffer.add(entry); 163 } 164 } 165 if (jc.isCancelled()) return null; 166 } 167 Log.v("DebugLoadingTime", "got " + buffer.size() + " buckets"); 168 } finally { 169 cursor.close(); 170 } 171 return buffer.toArray(new BucketEntry[buffer.size()]); 172 } 173 174 175 private static int findBucket(BucketEntry entries[], int bucketId) { 176 for (int i = 0, n = entries.length; i < n ; ++i) { 177 if (entries[i].bucketId == bucketId) return i; 178 } 179 return -1; 180 } 181 182 private class AlbumsLoader implements ThreadPool.Job<ArrayList<MediaSet>> { 183 184 @Override 185 @SuppressWarnings("unchecked") 186 public ArrayList<MediaSet> run(JobContext jc) { 187 // Note: it will be faster if we only select media_type and bucket_id. 188 // need to test the performance if that is worth 189 BucketEntry[] entries = loadBucketEntries(jc); 190 191 if (jc.isCancelled()) return null; 192 193 int offset = 0; 194 // Move camera and download bucket to the front, while keeping the 195 // order of others. 196 int index = findBucket(entries, MediaSetUtils.CAMERA_BUCKET_ID); 197 if (index != -1) { 198 circularShiftRight(entries, offset++, index); 199 } 200 index = findBucket(entries, MediaSetUtils.DOWNLOAD_BUCKET_ID); 201 if (index != -1) { 202 circularShiftRight(entries, offset++, index); 203 } 204 205 ArrayList<MediaSet> albums = new ArrayList<MediaSet>(); 206 DataManager dataManager = mApplication.getDataManager(); 207 for (BucketEntry entry : entries) { 208 MediaSet album = getLocalAlbum(dataManager, 209 mType, mPath, entry.bucketId, entry.bucketName); 210 album.reload(); 211 albums.add(album); 212 } 213 return albums; 214 } 215 } 216 217 private MediaSet getLocalAlbum( 218 DataManager manager, int type, Path parent, int id, String name) { 219 synchronized (DataManager.LOCK) { 220 Path path = parent.getChild(id); 221 MediaObject object = manager.peekMediaObject(path); 222 if (object != null) return (MediaSet) object; 223 switch (type) { 224 case MEDIA_TYPE_IMAGE: 225 return new LocalAlbum(path, mApplication, id, true, name); 226 case MEDIA_TYPE_VIDEO: 227 return new LocalAlbum(path, mApplication, id, false, name); 228 case MEDIA_TYPE_ALL: 229 Comparator<MediaItem> comp = DataManager.sDateTakenComparator; 230 return new LocalMergeAlbum(path, comp, new MediaSet[] { 231 getLocalAlbum(manager, MEDIA_TYPE_IMAGE, PATH_IMAGE, id, name), 232 getLocalAlbum(manager, MEDIA_TYPE_VIDEO, PATH_VIDEO, id, name)}, id); 233 } 234 throw new IllegalArgumentException(String.valueOf(type)); 235 } 236 } 237 238 public static String getBucketName(ContentResolver resolver, int bucketId) { 239 Uri uri = mBaseUri.buildUpon() 240 .appendQueryParameter("limit", "1") 241 .build(); 242 243 Cursor cursor = resolver.query( 244 uri, PROJECTION_BUCKET, "bucket_id = ?", 245 new String[]{String.valueOf(bucketId)}, null); 246 247 if (cursor == null) { 248 Log.w(TAG, "query fail: " + uri); 249 return ""; 250 } 251 try { 252 return cursor.moveToNext() 253 ? cursor.getString(INDEX_BUCKET_NAME) 254 : ""; 255 } finally { 256 cursor.close(); 257 } 258 } 259 260 @Override 261 // synchronized on this function for 262 // 1. Prevent calling reload() concurrently. 263 // 2. Prevent calling onFutureDone() and reload() concurrently 264 public synchronized long reload() { 265 // "|" is used instead of "||" because we want to clear both flags. 266 if (mNotifierImage.isDirty() | mNotifierVideo.isDirty()) { 267 if (mLoadTask != null) mLoadTask.cancel(); 268 mLoadTask = mApplication.getThreadPool().submit(new AlbumsLoader(), this); 269 } 270 if (mLoadBuffer != null) { 271 mAlbums = mLoadBuffer; 272 mLoadBuffer = null; 273 mDataVersion = nextVersionNumber(); 274 } 275 return mDataVersion; 276 } 277 278 @Override 279 public synchronized void onFutureDone(Future<ArrayList<MediaSet>> future) { 280 if (mLoadTask != future) return; // ignore, wait for the latest task 281 mLoadBuffer = future.get(); 282 if (mLoadBuffer == null) mLoadBuffer = new ArrayList<MediaSet>(); 283 notifyContentChanged(); 284 } 285 286 // For debug only. Fake there is a ContentObserver.onChange() event. 287 void fakeChange() { 288 mNotifierImage.fakeChange(); 289 mNotifierVideo.fakeChange(); 290 } 291 292 private static class BucketEntry { 293 public String bucketName; 294 public int bucketId; 295 296 public BucketEntry(int id, String name) { 297 bucketId = id; 298 bucketName = Utils.ensureNotNull(name); 299 } 300 301 @Override 302 public int hashCode() { 303 return bucketId; 304 } 305 306 @Override 307 public boolean equals(Object object) { 308 if (!(object instanceof BucketEntry)) return false; 309 BucketEntry entry = (BucketEntry) object; 310 return bucketId == entry.bucketId; 311 } 312 } 313 314 // Circular shift the array range from a[i] to a[j] (inclusive). That is, 315 // a[i] -> a[i+1] -> a[i+2] -> ... -> a[j], and a[j] -> a[i] 316 private static <T> void circularShiftRight(T[] array, int i, int j) { 317 T temp = array[j]; 318 for (int k = j; k > i; k--) { 319 array[k] = array[k - 1]; 320 } 321 array[i] = temp; 322 } 323} 324