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;
  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                 try {
  72                     // Check if media is mounted or storage is built-in, if so,
  73                     // try and use external cache dir; otherwise use internal cache dir
  74                     final String cachePath =
  75                             MainApp.getAppContext().getExternalCacheDir().getPath() +
  76                             File.separator + CACHE_FOLDER;
  77                     Log_OC.d(TAG, "create dir: " + cachePath);
  78                     final File diskCacheDir = new File(cachePath);
  79                     mThumbnailCache = new DiskLruImageCache(
  80                             diskCacheDir,
  81                             DISK_CACHE_SIZE,
  82                             mCompressFormat,
  83                             mCompressQuality
  84                     );
  85                 } catch (Exception e) {
  86                     Log_OC.d(TAG, "Thumbnail cache could not be opened ", e);
  87                     mThumbnailCache = null;
  88                 }
  89                 mThumbnailCacheStarting = false; // Finished initialization
  90                 mThumbnailsDiskCacheLock.notifyAll(); // Wake any waiting threads
  91             }
  92             return null;
  93         }
  94     }
  95
  96
  97     public static void addBitmapToCache(String key, Bitmap bitmap) {
  98         synchronized (mThumbnailsDiskCacheLock) {
  99             if (mThumbnailCache != null) {
 100                 mThumbnailCache.put(key, bitmap);
 101             }
 102         }
 103     }
 104
 105
 106     public static Bitmap getBitmapFromDiskCache(String key) {
 107         synchronized (mThumbnailsDiskCacheLock) {
 108             // Wait while disk cache is started from background thread
 109             while (mThumbnailCacheStarting) {
 110                 try {
 111                     mThumbnailsDiskCacheLock.wait();
 112                 } catch (InterruptedException e) {}
 113             }
 114             if (mThumbnailCache != null) {
 115                 return (Bitmap) mThumbnailCache.getBitmap(key);
 116             }
 117         }
 118         return null;
 119     }
 120
 121
 122     public static boolean cancelPotentialWork(OCFile file, ImageView imageView) {
 123         final ThumbnailGenerationTask bitmapWorkerTask = getBitmapWorkerTask(imageView);
 124
 125         if (bitmapWorkerTask != null) {
 126             final OCFile bitmapData = bitmapWorkerTask.mFile;
 127             // If bitmapData is not yet set or it differs from the new data
 128             if (bitmapData == null || bitmapData != file) {
 129                 // Cancel previous task
 130                 bitmapWorkerTask.cancel(true);
 131             } else {
 132                 // The same work is already in progress
 133                 return false;
 134             }
 135         }
 136         // No task associated with the ImageView, or an existing task was cancelled
 137         return true;
 138     }
 139
 140     public static ThumbnailGenerationTask getBitmapWorkerTask(ImageView imageView) {
 141         if (imageView != null) {
 142             final Drawable drawable = imageView.getDrawable();
 143             if (drawable instanceof AsyncDrawable) {
 144                 final AsyncDrawable asyncDrawable = (AsyncDrawable) drawable;
 145                 return asyncDrawable.getBitmapWorkerTask();
 146             }
 147          }
 148          return null;
 149      }
 150
 151     public static class ThumbnailGenerationTask extends AsyncTask<OCFile, Void, Bitmap> {
 152         private final WeakReference<ImageView> mImageViewReference;
 153         private OCFile mFile;
 154         private FileDataStorageManager mStorageManager;
 155
 156         public ThumbnailGenerationTask(ImageView imageView, FileDataStorageManager storageManager) {
 157          // Use a WeakReference to ensure the ImageView can be garbage collected
 158             mImageViewReference = new WeakReference<ImageView>(imageView);
 159             if (storageManager == null)
 160                 throw new IllegalArgumentException("storageManager must not be NULL");
 161             mStorageManager = storageManager;
 162         }
 163
 164         // Decode image in background.
 165         @Override
 166         protected Bitmap doInBackground(OCFile... params) {
 167             Bitmap thumbnail = null;
 168
 169             try {
 170                 mFile = params[0];
 171                 final String imageKey = String.valueOf(mFile.getRemoteId());
 172
 173                 // Check disk cache in background thread
 174                 thumbnail = getBitmapFromDiskCache(imageKey);
 175
 176                 // Not found in disk cache
 177                 if (thumbnail == null || mFile.needsUpdateThumbnail()) {
 178                     // Converts dp to pixel
 179                     Resources r = MainApp.getAppContext().getResources();
 180                     int px = (int) Math.round(TypedValue.applyDimension(
 181                             TypedValue.COMPLEX_UNIT_DIP, 150, r.getDisplayMetrics()
 182                     ));
 183
 184                     if (mFile.isDown()){
 185                         Bitmap bitmap = BitmapUtils.decodeSampledBitmapFromFile(
 186                                 mFile.getStoragePath(), px, px);
 187
 188                         if (bitmap != null) {
 189                             thumbnail = ThumbnailUtils.extractThumbnail(bitmap, px, px);
 190
 191                             // Add thumbnail to cache
 192                             addBitmapToCache(imageKey, thumbnail);
 193
 194                             mFile.setNeedsUpdateThumbnail(false);
 195                             mStorageManager.saveFile(mFile);
 196                         }
 197
 198                     }
 199                 }
 200
 201             } catch (Throwable t) {
 202                 // the app should never break due to a problem with thumbnails
 203                 Log_OC.e(TAG, "Generation of thumbnail for " + mFile + " failed", t);
 204                 if (t instanceof OutOfMemoryError) {
 205                     System.gc();
 206                 }
 207             }
 208
 209             return thumbnail;
 210         }
 211
 212         protected void onPostExecute(Bitmap bitmap){
 213             if (isCancelled()) {
 214                 bitmap = null;
 215             }
 216
 217             if (mImageViewReference != null && bitmap != null) {
 218                 final ImageView imageView = mImageViewReference.get();
 219                 final ThumbnailGenerationTask bitmapWorkerTask =
 220                         getBitmapWorkerTask(imageView);
 221                 if (this == bitmapWorkerTask && imageView != null) {
 222                     if (imageView.getTag().equals(mFile.getFileId())) {
 223                         imageView.setImageBitmap(bitmap);
 224                     }
 225                 }
 226             }
 227         }
 228     }
 229
 230
 231     public static class AsyncDrawable extends BitmapDrawable {
 232         private final WeakReference<ThumbnailGenerationTask> bitmapWorkerTaskReference;
 233
 234         public AsyncDrawable(
 235                 Resources res, Bitmap bitmap, ThumbnailGenerationTask bitmapWorkerTask
 236             ) {
 237
 238             super(res, bitmap);
 239             bitmapWorkerTaskReference =
 240                 new WeakReference<ThumbnailGenerationTask>(bitmapWorkerTask);
 241         }
 242
 243         public ThumbnailGenerationTask getBitmapWorkerTask() {
 244             return bitmapWorkerTaskReference.get();
 245         }
 246     }
 247
 248
 249     /**
 250      * Remove from cache the remoteId passed
 251      * @param fileRemoteId: remote id of mFile passed
 252      */
 253     public static void removeFileFromCache(String fileRemoteId){
 254         synchronized (mThumbnailsDiskCacheLock) {
 255             if (mThumbnailCache != null) {
 256                 mThumbnailCache.removeKey(fileRemoteId);
 257             }
 258             mThumbnailsDiskCacheLock.notifyAll(); // Wake any waiting threads
 259         }
 260     }
 261
 262 }