src/com/owncloud/android/datamodel/ThumbnailsCacheManager.java

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012-2014 ownCloud Inc.
   3  *
   4  *   This program is free software: you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License version 2,
   6  *   as published by the Free Software Foundation.
   7  *
   8  *   This program is distributed in the hope that it will be useful,
   9  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  *   GNU General Public License for more details.
  12  *
  13  *   You should have received a copy of the GNU General Public License
  14  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  *
  16  */
  17
  18 package com.owncloud.android.datamodel;
  19
  20 import java.io.File;
  21 import java.lang.ref.WeakReference;
  22
  23 import android.content.res.Resources;
  24 import android.graphics.Bitmap;
  25 import android.graphics.BitmapFactory;
  26 import android.graphics.Bitmap.CompressFormat;
  27 import android.graphics.drawable.BitmapDrawable;
  28 import android.graphics.drawable.Drawable;
  29 import android.media.ThumbnailUtils;
  30 import android.os.AsyncTask;
  31 import android.util.TypedValue;
  32 import android.widget.ImageView;
  33
  34 import com.owncloud.android.MainApp;
  35 import com.owncloud.android.lib.common.utils.Log_OC;
  36 import com.owncloud.android.ui.adapter.DiskLruImageCache;
  37 import com.owncloud.android.utils.BitmapUtils;
  38 import com.owncloud.android.utils.DisplayUtils;
  39
  40 /**
  41  * Manager for concurrent access to thumbnails cache.
  42  *
  43  * @author Tobias Kaminsky
  44  * @author David A. Velasco
  45  */
  46 public class ThumbnailsCacheManager {
  47
  48     private static final String TAG = ThumbnailsCacheManager.class.getSimpleName();
  49
  50     private static final String CACHE_FOLDER = "thumbnailCache";
  51
  52     private static final Object mThumbnailsDiskCacheLock = new Object();
  53     private static DiskLruImageCache mThumbnailCache = null;
  54     private static boolean mThumbnailCacheStarting = true;
  55
  56     private static final int DISK_CACHE_SIZE = 1024 * 1024 * 10; // 10MB
  57     private static final CompressFormat mCompressFormat = CompressFormat.JPEG;
  58     private static final int mCompressQuality = 70;
  59
  60     public static Bitmap mDefaultImg =
  61             BitmapFactory.decodeResource(
  62                     MainApp.getAppContext().getResources(),
  63                     DisplayUtils.getResourceId("image/png", "default.png")
  64             );
  65
  66
  67     public static class InitDiskCacheTask extends AsyncTask<File, Void, Void> {
  68         @Override
  69         protected Void doInBackground(File... params) {
  70             synchronized (mThumbnailsDiskCacheLock) {
  71                 mThumbnailCacheStarting = true;
  72                 if (mThumbnailCache == null) {
  73                     try {
  74                         // Check if media is mounted or storage is built-in, if so,
  75                         // try and use external cache dir; otherwise use internal cache dir
  76                         final String cachePath =
  77                                 MainApp.getAppContext().getExternalCacheDir().getPath() +
  78                                 File.separator + CACHE_FOLDER;
  79                         Log_OC.d(TAG, "create dir: " + cachePath);
  80                         final File diskCacheDir = new File(cachePath);
  81                         mThumbnailCache = new DiskLruImageCache(
  82                                 diskCacheDir,
  83                                 DISK_CACHE_SIZE,
  84                                 mCompressFormat,
  85                                 mCompressQuality
  86                         );
  87                     } catch (Exception e) {
  88                         Log_OC.d(TAG, "Thumbnail cache could not be opened ", e);
  89                         mThumbnailCache = null;
  90                     }
  91                 }
  92                 mThumbnailCacheStarting = false; // Finished initialization
  93                 mThumbnailsDiskCacheLock.notifyAll(); // Wake any waiting threads
  94             }
  95             return null;
  96         }
  97     }
  98
  99
 100     public static void addBitmapToCache(String key, Bitmap bitmap) {
 101         synchronized (mThumbnailsDiskCacheLock) {
 102             if (mThumbnailCache != null) {
 103                 mThumbnailCache.put(key, bitmap);
 104             }
 105         }
 106     }
 107
 108
 109     public static Bitmap getBitmapFromDiskCache(String key) {
 110         synchronized (mThumbnailsDiskCacheLock) {
 111             // Wait while disk cache is started from background thread
 112             while (mThumbnailCacheStarting) {
 113                 try {
 114                     mThumbnailsDiskCacheLock.wait();
 115                 } catch (InterruptedException e) {}
 116             }
 117             if (mThumbnailCache != null) {
 118                 return (Bitmap) mThumbnailCache.getBitmap(key);
 119             }
 120         }
 121         return null;
 122     }
 123
 124
 125     public static boolean cancelPotentialWork(OCFile file, ImageView imageView) {
 126         final ThumbnailGenerationTask bitmapWorkerTask = getBitmapWorkerTask(imageView);
 127
 128         if (bitmapWorkerTask != null) {
 129             final OCFile bitmapData = bitmapWorkerTask.mFile;
 130             // If bitmapData is not yet set or it differs from the new data
 131             if (bitmapData == null || bitmapData != file) {
 132                 // Cancel previous task
 133                 bitmapWorkerTask.cancel(true);
 134             } else {
 135                 // The same work is already in progress
 136                 return false;
 137             }
 138         }
 139         // No task associated with the ImageView, or an existing task was cancelled
 140         return true;
 141     }
 142
 143     public static ThumbnailGenerationTask getBitmapWorkerTask(ImageView imageView) {
 144         if (imageView != null) {
 145             final Drawable drawable = imageView.getDrawable();
 146             if (drawable instanceof AsyncDrawable) {
 147                 final AsyncDrawable asyncDrawable = (AsyncDrawable) drawable;
 148                 return asyncDrawable.getBitmapWorkerTask();
 149             }
 150          }
 151          return null;
 152      }
 153
 154     public static class ThumbnailGenerationTask extends AsyncTask<OCFile, Void, Bitmap> {
 155         private final WeakReference<ImageView> mImageViewReference;
 156         private OCFile mFile;
 157         private FileDataStorageManager mStorageManager;
 158
 159         public ThumbnailGenerationTask(ImageView imageView, FileDataStorageManager storageManager) {
 160          // Use a WeakReference to ensure the ImageView can be garbage collected
 161             mImageViewReference = new WeakReference<ImageView>(imageView);
 162             if (storageManager == null)
 163                 throw new IllegalArgumentException("storageManager must not be NULL");
 164             mStorageManager = storageManager;
 165         }
 166
 167         // Decode image in background.
 168         @Override
 169         protected Bitmap doInBackground(OCFile... params) {
 170             Bitmap thumbnail = null;
 171
 172             try {
 173                 mFile = params[0];
 174                 final String imageKey = String.valueOf(mFile.getRemoteId());
 175
 176                 // Check disk cache in background thread
 177                 thumbnail = getBitmapFromDiskCache(imageKey);
 178
 179                 // Not found in disk cache
 180                 if (thumbnail == null || mFile.needsUpdateThumbnail()) {
 181                     // Converts dp to pixel
 182                     Resources r = MainApp.getAppContext().getResources();
 183                     int px = (int) Math.round(TypedValue.applyDimension(
 184                             TypedValue.COMPLEX_UNIT_DIP, 150, r.getDisplayMetrics()
 185                     ));
 186
 187                     if (mFile.isDown()){
 188                         Bitmap bitmap = BitmapUtils.decodeSampledBitmapFromFile(
 189                                 mFile.getStoragePath(), px, px);
 190
 191                         if (bitmap != null) {
 192                             thumbnail = ThumbnailUtils.extractThumbnail(bitmap, px, px);
 193
 194                             // Add thumbnail to cache
 195                             addBitmapToCache(imageKey, thumbnail);
 196
 197                             mFile.setNeedsUpdateThumbnail(false);
 198                             mStorageManager.saveFile(mFile);
 199                         }
 200
 201                     }
 202                 }
 203
 204             } catch (Throwable t) {
 205                 // the app should never break due to a problem with thumbnails
 206                 Log_OC.e(TAG, "Generation of thumbnail for " + mFile + " failed", t);
 207                 if (t instanceof OutOfMemoryError) {
 208                     System.gc();
 209                 }
 210             }
 211
 212             return thumbnail;
 213         }
 214
 215         protected void onPostExecute(Bitmap bitmap){
 216             if (isCancelled()) {
 217                 bitmap = null;
 218             }
 219
 220             if (mImageViewReference != null && bitmap != null) {
 221                 final ImageView imageView = mImageViewReference.get();
 222                 final ThumbnailGenerationTask bitmapWorkerTask =
 223                         getBitmapWorkerTask(imageView);
 224                 if (this == bitmapWorkerTask && imageView != null) {
 225                     if (imageView.getTag().equals(mFile.getFileId())) {
 226                         imageView.setImageBitmap(bitmap);
 227                     }
 228                 }
 229             }
 230         }
 231     }
 232
 233
 234     public static class AsyncDrawable extends BitmapDrawable {
 235         private final WeakReference<ThumbnailGenerationTask> bitmapWorkerTaskReference;
 236
 237         public AsyncDrawable(
 238                 Resources res, Bitmap bitmap, ThumbnailGenerationTask bitmapWorkerTask
 239             ) {
 240
 241             super(res, bitmap);
 242             bitmapWorkerTaskReference =
 243                 new WeakReference<ThumbnailGenerationTask>(bitmapWorkerTask);
 244         }
 245
 246         public ThumbnailGenerationTask getBitmapWorkerTask() {
 247             return bitmapWorkerTaskReference.get();
 248         }
 249     }
 250
 251
 252     /**
 253      * Remove from cache the remoteId passed
 254      * @param fileRemoteId: remote id of mFile passed
 255      */
 256     public static void removeFileFromCache(String fileRemoteId){
 257         synchronized (mThumbnailsDiskCacheLock) {
 258             if (mThumbnailCache != null) {
 259                 mThumbnailCache.removeKey(fileRemoteId);
 260             }
 261             mThumbnailsDiskCacheLock.notifyAll(); // Wake any waiting threads
 262         }
 263     }
 264
 265 }