+
+    /**
+     * Class waiting for broadcast events from the {@link FielDownloader} service.
+     * 
+     * Updates the UI when a download is started or finished, provided that it is relevant for the
+     * folder displayed in the gallery.
+     */
+    private class DownloadFinishReceiver extends BroadcastReceiver {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            String accountName = intent.getStringExtra(FileDownloader.ACCOUNT_NAME);
+            String downloadedRemotePath = intent.getStringExtra(FileDownloader.EXTRA_REMOTE_PATH);
+            if (getAccount().name.equals(accountName) && 
+                    downloadedRemotePath != null) {
+
+                OCFile file = mStorageManager.getFileByPath(downloadedRemotePath);
+                int position = mPreviewImagePagerAdapter.getFilePosition(file);
+                boolean downloadWasFine = intent.getBooleanExtra(FileDownloader.EXTRA_DOWNLOAD_RESULT, false);
+                //boolean isOffscreen =  Math.abs((mViewPager.getCurrentItem() - position)) <= mViewPager.getOffscreenPageLimit();
+                
+                if (position >= 0 && intent.getAction().equals(FileDownloader.DOWNLOAD_FINISH_MESSAGE)) {
+                    if (downloadWasFine) {
+                        mPreviewImagePagerAdapter.updateFile(position, file);   
+                        
+                    } else {
+                        mPreviewImagePagerAdapter.updateWithDownloadError(position);
+                    }
+                    mPreviewImagePagerAdapter.notifyDataSetChanged();   // will trigger the creation of new fragments
+                    
+                } else {
+                    Log_OC.d(TAG, "Download finished, but the fragment is offscreen");
+                }
+                
+            }
+            removeStickyBroadcast(intent);
+        }
+
+    }
+
+
+    @Override
+    public boolean onTouch(View v, MotionEvent event) {
+        if (event.getAction() == MotionEvent.ACTION_UP) {
+           toggleFullScreen();
+        }
+        return true;
+    }
+
+    
+    private void toggleFullScreen() {
+        ActionBar actionBar = getSupportActionBar();
+        if (mFullScreen) {
+            actionBar.show();
+            
+        } else {
+            actionBar.hide();
+            
+        }
+        mFullScreen = !mFullScreen;
+    }
+
+    @Override
+    protected void onAccountSet(boolean stateWasRecovered) {
+        if (getAccount() != null) {
+            OCFile file = getFile();
+            /// Validate handled file  (first image to preview)
+            if (file == null) {
+                throw new IllegalStateException("Instanced with a NULL OCFile");
+            }
+            if (!file.isImage()) {
+                throw new IllegalArgumentException("Non-image file passed as argument");
+            }
+            mStorageManager = new FileDataStorageManager(getAccount(), getContentResolver());
+            file = mStorageManager.getFileById(file.getFileId()); 
+            if (file != null) {
+                /// Refresh the activity according to the Account and OCFile set
+                setFile(file);  // reset after getting it fresh from mStorageManager
+                getSupportActionBar().setTitle(getFile().getFileName());
+                //if (!stateWasRecovered) {
+                    initViewPager();
+                //}
+
+            } else {
+                // handled file not in the current Account
+                finish();
+            }
+            
+        } else {
+            Log_OC.wtf(TAG, "onAccountChanged was called with NULL account associated!");
+        }
+    }
+    
+