fix for #857

src/main/java/com/owncloud/android/datamodel/FileDataStorageManager.java

@@ -27,6 +27,7 @@ import android.content.ContentProviderResult;
 import android.content.ContentResolver;
 import android.content.ContentUris;
 import android.content.ContentValues;
+import android.content.Context;
 import android.content.Intent;
 import android.content.OperationApplicationException;
 import android.database.Cursor;
@@ -36,7 +37,10 @@ import android.provider.MediaStore;
 
 import com.owncloud.android.MainApp;
 import com.owncloud.android.db.ProviderMeta.ProviderTableMeta;
+import com.owncloud.android.lib.common.operations.RemoteOperationResult;
 import com.owncloud.android.lib.common.utils.Log_OC;
+import com.owncloud.android.lib.resources.files.ReadRemoteFileOperation;
+import com.owncloud.android.lib.resources.files.RemoteFile;
 import com.owncloud.android.lib.resources.shares.OCShare;
 import com.owncloud.android.lib.resources.shares.ShareType;
 import com.owncloud.android.lib.resources.status.CapabilityBooleanType;
@@ -247,6 +251,39 @@ public class FileDataStorageManager {
         return overriden;
     }
 
+    public long saveFileWithParent(OCFile file, Context context) {
+        if (file.getParentId() != 0 || file.getRemotePath().equals("/")) {
+            saveFile(file);
+
+        } else {
+            String remotePath = file.getRemotePath();
+            String parentPath = remotePath.substring(0, remotePath.lastIndexOf(file.getFileName()));
+
+            OCFile parentFile = getFileByPath(parentPath);
+
+            long fileId;
+            if (parentFile == null) {
+                // remote request
+                ReadRemoteFileOperation operation = new ReadRemoteFileOperation(parentPath);
+                RemoteOperationResult result = operation.execute(getAccount(), context);
+                if (result.isSuccess()) {
+                    OCFile remoteFolder = FileStorageUtils.fillOCFile((RemoteFile) result.getData().get(0));
+
+                    fileId = saveFileWithParent(remoteFolder, context);
+                } else {
+                    fileId = -1;
+                    Log_OC.e(TAG, "Error during saving file with parents: " + file.getRemotePath());
+                }
+            } else {
+                fileId = saveFileWithParent(parentFile, context);
+            }
+
+            file.setParentId(fileId);
+            saveFile(file);
+        }
+
+        return getFileByPath(file.getRemotePath()).getFileId();
+    }
 
     public void saveNewFile(OCFile newFile) {
         String remoteParentPath = new File(newFile.getRemotePath()).getParent();
@@ -868,6 +905,15 @@ public class FileDataStorageManager {
         return c;
     }
 
+    private OCFile createFileInstanceFromVirtual(Cursor c) {
+        OCFile file = null;
+        if (c != null) {
+            long fileId = c.getLong(c.getColumnIndex(ProviderTableMeta.VIRTUAL_OCFILE_ID));
+            file = getFileById(fileId);
+        }
+
+        return file;
+    }
 
     private OCFile createFileInstance(Cursor c) {
         OCFile file = null;
@@ -2005,4 +2051,89 @@ public class FileDataStorageManager {
         return capability;
     }
 
+    public void deleteVirtuals(VirtualFolderType type) {
+        if (getContentResolver() != null) {
+            getContentResolver().delete(ProviderTableMeta.CONTENT_URI_VIRTUAL,
+                    ProviderTableMeta.VIRTUAL_TYPE + "=?", new String[]{String.valueOf(type)});
+        } else {
+            try {
+                getContentProviderClient().delete(ProviderTableMeta.CONTENT_URI_VIRTUAL,
+                        ProviderTableMeta.VIRTUAL_TYPE + "=?", new String[]{String.valueOf(type)});
+            } catch (RemoteException e) {
+                Log_OC.e(TAG, FAILED_TO_INSERT_MSG + e.getMessage(), e);
+            }
+        }
+    }
+
+    public void saveVirtual(VirtualFolderType type, OCFile file) {
+        ContentValues cv = new ContentValues();
+        cv.put(ProviderTableMeta.VIRTUAL_TYPE, type.toString());
+        cv.put(ProviderTableMeta.VIRTUAL_OCFILE_ID, file.getFileId());
+
+        if (getContentResolver() != null) {
+            getContentResolver().insert(ProviderTableMeta.CONTENT_URI_VIRTUAL, cv);
+        } else {
+            try {
+                getContentProviderClient().insert(ProviderTableMeta.CONTENT_URI_VIRTUAL, cv);
+            } catch (RemoteException e) {
+                Log_OC.e(TAG, FAILED_TO_INSERT_MSG + e.getMessage(), e);
+            }
+        }
+    }
+
+    public Vector<OCFile> getVirtualFolderContent(VirtualFolderType type, boolean onlyImages) {
+        Vector<OCFile> ocFiles = new Vector<>();
+        Uri req_uri = ProviderTableMeta.CONTENT_URI_VIRTUAL;
+        Cursor c;
+
+        if (getContentProviderClient() != null) {
+            try {
+                c = getContentProviderClient().query(
+                        req_uri,
+                        null,
+                        ProviderTableMeta.VIRTUAL_TYPE + "=?",
+                        new String[]{String.valueOf(type)},
+                        null
+                );
+            } catch (RemoteException e) {
+                Log_OC.e(TAG, e.getMessage(), e);
+                return ocFiles;
+            }
+        } else {
+            c = getContentResolver().query(
+                    req_uri,
+                    null,
+                    ProviderTableMeta.VIRTUAL_TYPE + "=?",
+                    new String[]{String.valueOf(type)},
+                    null
+            );
+        }
+
+        if (c != null && c.moveToFirst()) {
+            do {
+                OCFile child = createFileInstanceFromVirtual(c);
+                    ocFiles.add(child);
+            } while (c.moveToNext());
+            c.close();
+        }
+
+        if (onlyImages) {
+            OCFile current = null;
+            Vector<OCFile> temp = new Vector<>();
+            for (int i=0; i < ocFiles.size(); i++) {
+                current = ocFiles.get(i);
+                if (MimeTypeUtil.isImage(current)) {
+                    temp.add(current);
+                }
+            }
+            ocFiles = temp;
+        }
+
+        if (ocFiles.size() > 0) {
+            Collections.sort(ocFiles);
+        }
+
+        return ocFiles;
+    }
+
 }

src/main/java/com/owncloud/android/datamodel/VirtualFolderType.java

@@ -0,0 +1,30 @@
+/**
+ * Nextcloud Android client application
+ *
+ * @author Tobias Kaminsky
+ * Copyright (C) 2017 Tobias Kaminsky
+ * Copyright (C) 2017 Nextcloud GmbH.
+ * <p>
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * at your option) any later version.
+ * <p>
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ * <p>
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.owncloud.android.datamodel;
+
+/**
+ * Type for virtual folders
+ */
+
+public enum VirtualFolderType {
+    FAVORITE, PHOTOS, NONE
+}

src/main/java/com/owncloud/android/db/ProviderMeta.java

@@ -32,7 +32,7 @@ import com.owncloud.android.MainApp;
 public class ProviderMeta {
 
     public static final String DB_NAME = "filelist";
-    public static final int DB_VERSION = 19;
+    public static final int DB_VERSION = 20;
 
     private ProviderMeta() {
     }
@@ -44,6 +44,7 @@ public class ProviderMeta {
         public static final String UPLOADS_TABLE_NAME = "list_of_uploads";
         public static final String SYNCED_FOLDERS_TABLE_NAME = "synced_folders";
         public static final String EXTERNAL_LINKS_TABLE_NAME = "external_links";
+        public static final String VIRTUAL_TABLE_NAME = "virtual";
 
         private static final String CONTENT_PREFIX = "content://";
 
@@ -63,6 +64,7 @@ public class ProviderMeta {
                 + MainApp.getAuthority() + "/synced_folders");
         public static final Uri CONTENT_URI_EXTERNAL_LINKS = Uri.parse(CONTENT_PREFIX
                 + MainApp.getAuthority() + "/external_links");
+        public static final Uri CONTENT_URI_VIRTUAL = Uri.parse(CONTENT_PREFIX + MainApp.getAuthority() + "/virtual");
 
         public static final String CONTENT_TYPE = "vnd.android.cursor.dir/vnd.owncloud.file";
         public static final String CONTENT_TYPE_ITEM = "vnd.android.cursor.item/vnd.owncloud.file";
@@ -177,5 +179,9 @@ public class ProviderMeta {
         public static final String EXTERNAL_LINKS_TYPE = "type";
         public static final String EXTERNAL_LINKS_NAME = "name";
         public static final String EXTERNAL_LINKS_URL = "url";
+
+        // Columns of virtual
+        public static final String VIRTUAL_TYPE = "type";
+        public static final String VIRTUAL_OCFILE_ID = "ocfile_id";
     }
 }

src/main/java/com/owncloud/android/providers/FileContentProvider.java

@@ -72,6 +72,7 @@ public class FileContentProvider extends ContentProvider {
     private static final int UPLOADS = 6;
     private static final int SYNCED_FOLDERS = 7;
     private static final int EXTERNAL_LINKS = 8;
+    private static final int VIRTUAL = 9;
 
     private static final String TAG = FileContentProvider.class.getSimpleName();
 
@@ -201,6 +202,9 @@ public class FileContentProvider extends ContentProvider {
             case EXTERNAL_LINKS:
                 count = db.delete(ProviderTableMeta.EXTERNAL_LINKS_TABLE_NAME, where, whereArgs);
                 break;
+            case VIRTUAL:
+                count = db.delete(ProviderTableMeta.VIRTUAL_TABLE_NAME, where, whereArgs);
+                break;
             default:
                 //Log_OC.e(TAG, "Unknown uri " + uri);
                 throw new IllegalArgumentException("Unknown uri: " + uri.toString());
@@ -335,6 +339,18 @@ public class FileContentProvider extends ContentProvider {
                 }
                 return insertedExternalLinkUri;
 
+            case VIRTUAL:
+                Uri insertedVirtualUri;
+                long virtualId = db.insert(ProviderTableMeta.VIRTUAL_TABLE_NAME, null, values);
+
+                if (virtualId > 0) {
+                    insertedVirtualUri = ContentUris.withAppendedId(ProviderTableMeta.CONTENT_URI_VIRTUAL, virtualId);
+                } else {
+                    throw new SQLException("ERROR " + uri);
+                }
+
+                return insertedVirtualUri;
+
             default:
                 throw new IllegalArgumentException("Unknown uri id: " + uri);
         }
@@ -385,6 +401,7 @@ public class FileContentProvider extends ContentProvider {
         mUriMatcher.addURI(authority, "uploads/#", UPLOADS);
         mUriMatcher.addURI(authority, "synced_folders", SYNCED_FOLDERS);
         mUriMatcher.addURI(authority, "external_links", EXTERNAL_LINKS);
+        mUriMatcher.addURI(authority, "virtual", VIRTUAL);
 
         return true;
     }
@@ -473,6 +490,12 @@ public class FileContentProvider extends ContentProvider {
                             + uri.getPathSegments().get(1));
                 }
                 break;
+            case VIRTUAL:
+                sqlQuery.setTables(ProviderTableMeta.VIRTUAL_TABLE_NAME);
+                if (uri.getPathSegments().size() > 1) {
+                    sqlQuery.appendWhere(ProviderTableMeta._ID + "=" + uri.getPathSegments().get(1));
+                }
+                break;
             default:
                 throw new IllegalArgumentException("Unknown uri id: " + uri);
         }
@@ -495,6 +518,9 @@ public class FileContentProvider extends ContentProvider {
                 case EXTERNAL_LINKS:
                     order = ProviderTableMeta.EXTERNAL_LINKS_NAME;
                     break;
+                case VIRTUAL:
+                    order = ProviderTableMeta.VIRTUAL_TYPE;
+                    break;
                 default: // Files
                     order = ProviderTableMeta.FILE_DEFAULT_SORT_ORDER;
                     break;
@@ -611,6 +637,9 @@ public class FileContentProvider extends ContentProvider {
 
             // Create external links table
             createExternalLinksTable(db);
+
+            // Create virtual table
+            createVirtualTable(db);
         }
 
         @Override
@@ -927,6 +956,22 @@ public class FileContentProvider extends ContentProvider {
             if (!upgraded) {
                 Log_OC.i(SQL, String.format(Locale.ENGLISH, UPGRADE_VERSION_MSG, oldVersion, newVersion));
             }
+
+            if (oldVersion < 20 && newVersion >= 20) {
+                Log_OC.i(SQL, "Adding virtual table");
+                db.beginTransaction();
+                try {
+                    createVirtualTable(db);
+                    upgraded = true;
+                    db.setTransactionSuccessful();
+                } finally {
+                    db.endTransaction();
+                }
+            }
+
+            if (!upgraded) {
+                Log_OC.i(SQL, String.format(Locale.ENGLISH, UPGRADE_VERSION_MSG, oldVersion, newVersion));
+            }
         }
     }
 
@@ -1064,6 +1109,14 @@ public class FileContentProvider extends ContentProvider {
         );
     }
 
+    private void createVirtualTable(SQLiteDatabase db) {
+        db.execSQL("CREATE TABLE " + ProviderTableMeta.VIRTUAL_TABLE_NAME + "("
+                + ProviderTableMeta._ID + " INTEGER PRIMARY KEY, "          // id
+                + ProviderTableMeta.VIRTUAL_TYPE + " TEXT, "                // type
+                + ProviderTableMeta.VIRTUAL_OCFILE_ID + " INTEGER )"        // file id
+        );
+    }
+
     /**
      * Version 10 of database does not modify its scheme. It coincides with the upgrade of the ownCloud account names
      * structure to include in it the path to the server instance. Updating the account names and path to local files

src/main/java/com/owncloud/android/ui/activity/FileDisplayActivity.java

@@ -62,6 +62,7 @@ import com.owncloud.android.MainApp;
 import com.owncloud.android.R;
 import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
+import com.owncloud.android.datamodel.VirtualFolderType;
 import com.owncloud.android.db.PreferenceManager;
 import com.owncloud.android.files.services.FileDownloader;
 import com.owncloud.android.files.services.FileDownloader.FileDownloaderBinder;
@@ -1912,6 +1913,19 @@ public class FileDisplayActivity extends HookActivity
         showDetailsIntent.putExtra(EXTRA_FILE, file);
         showDetailsIntent.putExtra(EXTRA_ACCOUNT, getAccount());
         startActivity(showDetailsIntent);
+    }
+
+    /**
+     * Opens the image gallery showing the image {@link OCFile} received as parameter.
+     *
+     * @param file Image {@link OCFile} to show.
+     */
+    public void startImagePreview(OCFile file, VirtualFolderType type) {
+        Intent showDetailsIntent = new Intent(this, PreviewImageActivity.class);
+        showDetailsIntent.putExtra(PreviewImageActivity.EXTRA_FILE, file);
+        showDetailsIntent.putExtra(EXTRA_ACCOUNT, getAccount());
+        showDetailsIntent.putExtra(PreviewImageActivity.EXTRA_VIRTUAL_TYPE, type);
+        startActivity(showDetailsIntent);
 
     }
 

src/main/java/com/owncloud/android/ui/adapter/FileListListAdapter.java

@@ -46,6 +46,7 @@ import com.owncloud.android.authentication.AccountUtils;
 import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
 import com.owncloud.android.datamodel.ThumbnailsCacheManager;
+import com.owncloud.android.datamodel.VirtualFolderType;
 import com.owncloud.android.db.PreferenceManager;
 import com.owncloud.android.files.services.FileDownloader.FileDownloaderBinder;
 import com.owncloud.android.files.services.FileUploader.FileUploaderBinder;
@@ -485,37 +486,9 @@ public class FileListListAdapter extends BaseAdapter {
     public void setData(ArrayList<Object> objects, ExtendedListFragment.SearchType searchType) {
         mFiles = new Vector<>();
         if (searchType.equals(ExtendedListFragment.SearchType.SHARED_FILTER)) {
-            ArrayList<OCShare> shares = new ArrayList<>();
-            for (int i = 0; i < objects.size(); i++) {
-                // check type before cast as of long running data fetch it is possible that old result is filled
-                if (objects.get(i) instanceof OCShare) {
-                    OCShare ocShare = (OCShare) objects.get(i);
-
-                    shares.add(ocShare);
-
-                    // get ocFile from Server to have an up-to-date copy
-                    ReadRemoteFileOperation operation = new ReadRemoteFileOperation(ocShare.getPath());
-                    RemoteOperationResult result = operation.execute(mAccount, mContext);
-                    if (result.isSuccess()) {
-                        OCFile file = FileStorageUtils.fillOCFile((RemoteFile) result.getData().get(0));
-
-                        mStorageManager.saveFile(file);
-
-                        if (!mFiles.contains(file)) {
-                            mFiles.add(file);
-                        }
-                    } else {
-                        Log_OC.e(TAG, "Error in getting prop for file: " + ocShare.getPath());
-                    }
-                }
-            }
-            mStorageManager.saveShares(shares);
+            parseShares(objects);
         } else {
-            for (int i = 0; i < objects.size(); i++) {
-                OCFile ocFile = FileStorageUtils.fillOCFile((RemoteFile) objects.get(i));
-                searchForLocalFileInDefaultPath(ocFile);
-                mFiles.add(ocFile);
-            }
+           parseVirtuals(objects, searchType);
         }
 
         if (!searchType.equals(ExtendedListFragment.SearchType.PHOTO_SEARCH) &&
@@ -539,6 +512,62 @@ public class FileListListAdapter extends BaseAdapter {
         });
     }
 
+    private void parseShares(ArrayList<Object> objects) {
+        ArrayList<OCShare> shares = new ArrayList<>();
+        for (int i = 0; i < objects.size(); i++) {
+            // check type before cast as of long running data fetch it is possible that old result is filled
+            if (objects.get(i) instanceof OCShare) {
+                OCShare ocShare = (OCShare) objects.get(i);
+
+                shares.add(ocShare);
+
+                // get ocFile from Server to have an up-to-date copy
+                ReadRemoteFileOperation operation = new ReadRemoteFileOperation(ocShare.getPath());
+                RemoteOperationResult result = operation.execute(mAccount, mContext);
+                if (result.isSuccess()) {
+                    OCFile file = FileStorageUtils.fillOCFile((RemoteFile) result.getData().get(0));
+
+                    mStorageManager.saveFile(file);
+
+                    if (!mFiles.contains(file)) {
+                        mFiles.add(file);
+                    }
+                } else {
+                    Log_OC.e(TAG, "Error in getting prop for file: " + ocShare.getPath());
+                }
+            }
+        }
+        mStorageManager.saveShares(shares);
+    }
+
+    private void parseVirtuals(ArrayList<Object> objects, ExtendedListFragment.SearchType searchType) {
+        VirtualFolderType type;
+        boolean onlyImages = false;
+        switch (searchType) {
+            case FAVORITE_SEARCH:
+                type = VirtualFolderType.FAVORITE;
+                break;
+            case PHOTO_SEARCH:
+                type = VirtualFolderType.PHOTOS;
+                onlyImages = true;
+                break;
+            default:
+                type = VirtualFolderType.NONE;
+                break;
+        }
+
+        mStorageManager.deleteVirtuals(type);
+
+        for (int i = 0; i < objects.size(); i++) {
+            OCFile ocFile = FileStorageUtils.fillOCFile((RemoteFile) objects.get(i));
+            searchForLocalFileInDefaultPath(ocFile);
+            mStorageManager.saveFileWithParent(ocFile, mContext);
+            mStorageManager.saveVirtual(type, mStorageManager.getFileByPath(ocFile.getRemotePath()));
+        }
+
+        mFiles.addAll(mStorageManager.getVirtualFolderContent(type, onlyImages));
+    }
+
     /**
      * Filter for getting only the folders
      *

src/main/java/com/owncloud/android/ui/fragment/OCFileListFragment.java

@@ -59,6 +59,7 @@ import com.owncloud.android.R;
 import com.owncloud.android.authentication.AccountUtils;
 import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
+import com.owncloud.android.datamodel.VirtualFolderType;
 import com.owncloud.android.files.FileMenuFilter;
 import com.owncloud.android.lib.common.OwnCloudAccount;
 import com.owncloud.android.lib.common.OwnCloudClient;
@@ -808,7 +809,23 @@ public class OCFileListFragment extends ExtendedListFragment implements OCFileLi
             } else { /// Click on a file
                 if (PreviewImageFragment.canBePreviewed(file)) {
                     // preview image - it handles the download, if needed
-                    ((FileDisplayActivity) mContainerActivity).startImagePreview(file);
+                    if (searchFragment) {
+                        VirtualFolderType type;
+                        switch (currentSearchType) {
+                            case FAVORITE_SEARCH:
+                                type = VirtualFolderType.FAVORITE;
+                                break;
+                            case PHOTO_SEARCH:
+                                type = VirtualFolderType.PHOTOS;
+                                break;
+                            default:
+                                type = VirtualFolderType.NONE;
+                                break;
+                        }
+                        ((FileDisplayActivity) mContainerActivity).startImagePreview(file, type);
+                    } else {
+                        ((FileDisplayActivity) mContainerActivity).startImagePreview(file);
+                    }
                 } else if (file.isDown() && MimeTypeUtil.isVCard(file)){
                     ((FileDisplayActivity) mContainerActivity).startContactListFragment(file);
                 } else if (PreviewTextFragment.canBePreviewed(file)) {

src/main/java/com/owncloud/android/ui/preview/PreviewImageActivity.java

@@ -40,6 +40,7 @@ import com.owncloud.android.R;
 import com.owncloud.android.authentication.AccountUtils;
 import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
+import com.owncloud.android.datamodel.VirtualFolderType;
 import com.owncloud.android.files.services.FileDownloader;
 import com.owncloud.android.files.services.FileDownloader.FileDownloaderBinder;
 import com.owncloud.android.files.services.FileUploader;
@@ -72,6 +73,8 @@ public class PreviewImageActivity extends FileActivity implements
     private static final String KEY_WAITING_FOR_BINDER = "WAITING_FOR_BINDER";
     private static final String KEY_SYSTEM_VISIBLE = "TRUE";
 
+    public static final String EXTRA_VIRTUAL_TYPE = "EXTRA_VIRTUAL_TYPE";
+
     private ExtendedViewPager mViewPager;
     private PreviewImagePagerAdapter mPreviewImagePagerAdapter;
     private int mSavedPosition = 0;
@@ -129,25 +132,36 @@ public class PreviewImageActivity extends FileActivity implements
     }
 
     private void initViewPager() {
-        // get parent from path
-        String parentPath = getFile().getRemotePath().substring(0,
-                getFile().getRemotePath().lastIndexOf(getFile().getFileName()));
-        OCFile parentFolder = getStorageManager().getFileByPath(parentPath);
-        if (parentFolder == null) {
-            // should not be necessary
-            parentFolder = getStorageManager().getFileByPath(OCFile.ROOT_PATH);
-        }
+        // virtual folder
+        if (getIntent().getSerializableExtra(EXTRA_VIRTUAL_TYPE) != null) {
+            VirtualFolderType type = (VirtualFolderType) getIntent().getSerializableExtra(EXTRA_VIRTUAL_TYPE);
 
-        mPreviewImagePagerAdapter = new PreviewImagePagerAdapter(getSupportFragmentManager(),
-                parentFolder, getAccount(), getStorageManager(), MainApp.isOnlyOnDevice());
+            mPreviewImagePagerAdapter = new PreviewImagePagerAdapter(getSupportFragmentManager(),
+                    type, getAccount(), getStorageManager());
+        } else {
+            // get parent from path
+            String parentPath = getFile().getRemotePath().substring(0,
+                    getFile().getRemotePath().lastIndexOf(getFile().getFileName()));
+            OCFile parentFolder = getStorageManager().getFileByPath(parentPath);
+
+            if (parentFolder == null) {
+                // should not be necessary
+                parentFolder = getStorageManager().getFileByPath(OCFile.ROOT_PATH);
+            }
+
+            mPreviewImagePagerAdapter = new PreviewImagePagerAdapter(getSupportFragmentManager(),
+                    parentFolder, getAccount(), getStorageManager(), MainApp.isOnlyOnDevice());
+        }
 
         mViewPager = (ExtendedViewPager) findViewById(R.id.fragmentPager);
-        int position = mHasSavedPosition ? mSavedPosition :
-                mPreviewImagePagerAdapter.getFilePosition(getFile());
+
+        int position = mHasSavedPosition ? mSavedPosition : mPreviewImagePagerAdapter.getFilePosition(getFile());
         position = (position >= 0) ? position : 0;
-        mViewPager.setAdapter(mPreviewImagePagerAdapter); 
+
+        mViewPager.setAdapter(mPreviewImagePagerAdapter);
         mViewPager.setOnPageChangeListener(this);
         mViewPager.setCurrentItem(position);
+
         if (position == 0 && !getFile().isDown()) {
             // this is necessary because mViewPager.setCurrentItem(0) just after setting the
             // adapter does not result in a call to #onPageSelected(0)
@@ -230,9 +244,9 @@ public class PreviewImageActivity extends FileActivity implements
                 mUploaderBinder = null;
             }
         }
-    };    
-    
-    
+    }
+
+
     @Override
     public void onStop() {
         super.onStop();
@@ -449,7 +463,7 @@ public class PreviewImageActivity extends FileActivity implements
         super.onAccountSet(stateWasRecovered);
         if (getAccount() != null) {
             OCFile file = getFile();
-            /// Validate handled file  (first image to preview)
+            /// Validate handled file (first image to preview)
             if (file == null) {
                 throw new IllegalStateException("Instanced with a NULL OCFile");
             }

src/main/java/com/owncloud/android/ui/preview/PreviewImagePagerAdapter.java

@@ -27,6 +27,7 @@ import android.view.ViewGroup;
 
 import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
+import com.owncloud.android.datamodel.VirtualFolderType;
 import com.owncloud.android.ui.fragment.FileFragment;
 import com.owncloud.android.utils.FileStorageUtils;
 
@@ -87,7 +88,44 @@ public class PreviewImagePagerAdapter extends FragmentStatePagerAdapter {
         //mFragmentManager = fragmentManager;
         mCachedFragments = new HashMap<Integer, FileFragment>();
     }
-    
+
+    /**
+     * Constructor.
+     *
+     * @param fragmentManager {@link FragmentManager} instance that will handle
+     *                        the {@link Fragment}s provided by the adapter.
+     * @param type            Type of virtual folder, e.g. favorite or photos
+     * @param storageManager  Bridge to database.
+     */
+    public PreviewImagePagerAdapter(FragmentManager fragmentManager, VirtualFolderType type,
+                                    Account account, FileDataStorageManager storageManager) {
+        super(fragmentManager);
+
+        if (fragmentManager == null) {
+            throw new IllegalArgumentException("NULL FragmentManager instance");
+        }
+        if (type == null) {
+            throw new IllegalArgumentException("NULL parent folder");
+        }
+        if (storageManager == null) {
+            throw new IllegalArgumentException("NULL storage manager");
+        }
+
+        mAccount = account;
+        mStorageManager = storageManager;
+        mImageFiles = mStorageManager.getVirtualFolderContent(type, true);
+
+        if (type == VirtualFolderType.PHOTOS) {
+            mImageFiles = FileStorageUtils.sortOCFilesByDate(mImageFiles);
+        }
+
+        mObsoleteFragments = new HashSet<Object>();
+        mObsoletePositions = new HashSet<Integer>();
+        mDownloadErrors = new HashSet<Integer>();
+        //mFragmentManager = fragmentManager;
+        mCachedFragments = new HashMap<Integer, FileFragment>();
+    }
+
     /**
      * Returns the image files handled by the adapter.
      * 
@@ -195,7 +233,7 @@ public class PreviewImagePagerAdapter extends FragmentStatePagerAdapter {
     public void resetZoom() {
         Iterator<FileFragment> entries = mCachedFragments.values().iterator();
         while (entries.hasNext()) {
-        FileFragment fileFragment = (FileFragment) entries.next();
+        FileFragment fileFragment = entries.next();
             if (fileFragment instanceof PreviewImageFragment) {
                 ((PreviewImageFragment) fileFragment).getImageView().resetZoom();
             }