synchronize around thumbnail cache to avoid loading images twice

1 files changed, 13 insertions, 4 deletions

diff --git a/src/main/java/eu/siacs/conversations/persistance/FileBackend.java b/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
index 30609214..c63ce870 100644
--- a/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
+++ b/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
@@ -20,6 +20,7 @@ import android.system.StructStat;
 import android.util.Base64;
 import android.util.Base64OutputStream;
 import android.util.Log;
+import android.util.LruCache;
 import android.webkit.MimeTypeMap;
 
 import java.io.ByteArrayOutputStream;
@@ -344,10 +345,17 @@ public class FileBackend {
 		}
 	}
 
-	public Bitmap getThumbnail(Message message, int size, boolean cacheOnly)
-			throws FileNotFoundException {
-		Bitmap thumbnail = mXmppConnectionService.getBitmapCache().get(message.getUuid());
+	public Bitmap getThumbnail(Message message, int size, boolean cacheOnly) throws FileNotFoundException {
+		final String uuid = message.getUuid();
+		final LruCache<String,Bitmap> cache = mXmppConnectionService.getBitmapCache();
+		Log.d(Config.LOGTAG,"get thumbnail for "+uuid+" cacheOnly="+Boolean.toString(cacheOnly));
+		Bitmap thumbnail = cache.get(uuid);
 		if ((thumbnail == null) && (!cacheOnly)) {
+			synchronized (cache) {
+				thumbnail = cache.get(uuid);
+				if (thumbnail != null) {
+					return thumbnail;
+				}
 				File file = getFile(message);
 				BitmapFactory.Options options = new BitmapFactory.Options();
 				options.inSampleSize = calcSampleSize(file, size);
@@ -357,7 +365,8 @@ public class FileBackend {
 				}
 				thumbnail = resize(fullsize, size);
 				thumbnail = rotate(thumbnail, getRotation(file));
-			this.mXmppConnectionService.getBitmapCache().put(message.getUuid(),thumbnail);
+				this.mXmppConnectionService.getBitmapCache().put(uuid, thumbnail);
+			}
 		}
 		return thumbnail;
 	}