Minor changes after reviewing Bitmaps life cycle in PreviewImageFragment

src/com/owncloud/android/ui/preview/ImageViewCustom.java

@@ -12,10 +12,13 @@ import android.widget.ImageView;
 import com.owncloud.android.lib.common.utils.Log_OC;
 
 public class ImageViewCustom extends ImageView {
-    
+
+    private static final String TAG = ImageViewCustom.class.getSimpleName();
+
     private static final boolean IS_ICS_OR_HIGHER = Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH;
-    
-    private Bitmap mBitmap;
+
+    private int mBitmapHeight;
+    private int mBitmapWidth;
 
     
     public ImageViewCustom(Context context) {
@@ -45,26 +48,29 @@ public class ImageViewCustom extends ImageView {
 
     /**
      * Checks if current bitmaps exceed the maximum OpenGL texture size limit
-     * @param bitmap
-     * @return boolean
+     * @param canvas        Canvas where the view will be drawn into.
+     * @return boolean      True means that the bitmap is too big for the canvas.
      */
     @SuppressLint("NewApi")
 	private boolean checkIfMaximumBitmapExceed(Canvas canvas) {
-        Log_OC.d("OC", "Canvas maximum: " + canvas.getMaximumBitmapWidth() + " - " + canvas.getMaximumBitmapHeight());
-        if (mBitmap!= null && (mBitmap.getWidth() > canvas.getMaximumBitmapWidth() 
-                || mBitmap.getHeight() > canvas.getMaximumBitmapHeight())) {
+        Log_OC.v(TAG, "Canvas maximum: " + canvas.getMaximumBitmapWidth() + " - " + canvas.getMaximumBitmapHeight());
+        if (mBitmapWidth > canvas.getMaximumBitmapWidth()
+                || mBitmapHeight > canvas.getMaximumBitmapHeight()) {
             return true;
         }
         
         return false;
     }
     
+    @Override
     /**
-     * Set current bitmap
-     * @param bitmap
+     * Keeps the size of the bitmap cached in member variables for faster access in {@link #onDraw(Canvas)} ,
+     * but without keeping another reference to the {@link Bitmap}
      */
-    public void setBitmap (Bitmap bitmap) {
-        mBitmap = bitmap;
+    public void setImageBitmap (Bitmap bm) {
+        mBitmapWidth = bm.getWidth();
+        mBitmapHeight = bm.getHeight();
+        super.setImageBitmap(bm);
     }
 
 }

src/com/owncloud/android/ui/preview/PreviewImageFragment.java

@@ -202,12 +202,12 @@ public class PreviewImageFragment extends FileFragment {
     
     @Override
     public void onStop() {
-        super.onStop();
+        Log_OC.d(TAG, "onStop starts");
         if (mLoadBitmapTask != null) {
             mLoadBitmapTask.cancel(true);
             mLoadBitmapTask = null;
         }
-        
+        super.onStop();
     }
     
     /**
@@ -329,6 +329,8 @@ public class PreviewImageFragment extends FileFragment {
         if (mBitmap != null) {
             mBitmap.recycle();
             System.gc();
+                // putting this in onStop() is just the same; the fragment is always destroyed by the ViewPager
+                // when swipes further than the valid offset, and onStop() is never called before than that
         }
         super.onDestroy();
     }
@@ -415,7 +417,7 @@ public class PreviewImageFragment extends FileFragment {
                 }
                 
             } catch (OutOfMemoryError e) {
-                Log_OC.e(TAG, "Out of memory occured for file " + storagePath, e);
+                Log_OC.w(TAG, "Out of memory rendering file " + storagePath + " in full size; scaling down");
 
                 if (isCancelled()) return result;
                 
@@ -459,6 +461,10 @@ public class PreviewImageFragment extends FileFragment {
             } else {
                 showErrorMessage();
             }
+            if (mBitmap != result)  {
+                // unused bitmap, release it! (just in case)
+                result.recycle();
+            }
         }
         
         @SuppressLint("InlinedApi")
@@ -466,11 +472,10 @@ public class PreviewImageFragment extends FileFragment {
             if (mImageViewRef != null) {
                 final ImageViewCustom imageView = mImageViewRef.get();
                 if (imageView != null) {
-                    imageView.setBitmap(result);
                     imageView.setImageBitmap(result);
                     imageView.setVisibility(View.VISIBLE);
-                    mBitmap  = result;
-                } // else , silently finish, the fragment was destroyed
+                    mBitmap  = result;  // needs to be kept for recycling when not useful
+                }
             }
             if (mMessageViewRef != null) {
                 final TextView messageView = mMessageViewRef.get();