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

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012-2013 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 package com.owncloud.android.ui.preview;
  18
  19 import java.lang.ref.WeakReference;
  20 import java.util.ArrayList;
  21 import java.util.List;
  22
  23
  24 import android.accounts.Account;
  25 import android.annotation.SuppressLint;
  26 import android.app.Activity;
  27 import android.content.ActivityNotFoundException;
  28 import android.content.Intent;
  29 import android.graphics.Bitmap;
  30 import android.graphics.BitmapFactory;
  31 import android.graphics.BitmapFactory.Options;
  32 import android.graphics.Point;
  33 import android.net.Uri;
  34 import android.os.AsyncTask;
  35 import android.os.Bundle;
  36 import android.os.Handler;
  37 import android.support.v4.app.FragmentStatePagerAdapter;
  38 import android.view.Display;
  39 import android.view.LayoutInflater;
  40 import android.view.View;
  41 import android.view.View.OnTouchListener;
  42 import android.view.ViewGroup;
  43 import android.webkit.MimeTypeMap;
  44 import android.widget.ImageView;
  45 import android.widget.ProgressBar;
  46 import android.widget.TextView;
  47 import android.widget.Toast;
  48
  49 import com.actionbarsherlock.view.Menu;
  50 import com.actionbarsherlock.view.MenuInflater;
  51 import com.actionbarsherlock.view.MenuItem;
  52 import com.owncloud.android.R;
  53 import com.owncloud.android.datamodel.FileDataStorageManager;
  54 import com.owncloud.android.datamodel.OCFile;
  55 import com.owncloud.android.lib.common.network.WebdavUtils;
  56 import com.owncloud.android.lib.common.operations.OnRemoteOperationListener;
  57 import com.owncloud.android.lib.common.operations.RemoteOperation;
  58 import com.owncloud.android.lib.common.operations.RemoteOperationResult;
  59 import com.owncloud.android.operations.RemoveFileOperation;
  60 import com.owncloud.android.ui.activity.FileActivity;
  61 import com.owncloud.android.ui.fragment.ConfirmationDialogFragment;
  62 import com.owncloud.android.ui.fragment.FileFragment;
  63 import com.owncloud.android.utils.Log_OC;
  64
  65
  66 /**
  67  * This fragment shows a preview of a downloaded image.
  68  *
  69  * Trying to get an instance with NULL {@link OCFile} or ownCloud {@link Account} values will produce an {@link IllegalStateException}.
  70  *
  71  * If the {@link OCFile} passed is not downloaded, an {@link IllegalStateException} is generated on instantiation too.
  72  *
  73  * @author David A. Velasco
  74  */
  75 public class PreviewImageFragment extends FileFragment implements   OnRemoteOperationListener,
  76                                                                         ConfirmationDialogFragment.ConfirmationDialogFragmentListener {
  77     public static final String EXTRA_FILE = "FILE";
  78     public static final String EXTRA_ACCOUNT = "ACCOUNT";
  79
  80     private View mView;
  81     private Account mAccount;
  82     private FileDataStorageManager mStorageManager;
  83     private ImageView mImageView;
  84     private TextView mMessageView;
  85     private ProgressBar mProgressWheel;
  86
  87     public Bitmap mBitmap = null;
  88
  89     private Handler mHandler;
  90     private RemoteOperation mLastRemoteOperation;
  91
  92     private static final String TAG = PreviewImageFragment.class.getSimpleName();
  93
  94     private boolean mIgnoreFirstSavedState;
  95
  96
  97     /**
  98      * Creates a fragment to preview an image.
  99      *
 100      * When 'imageFile' or 'ocAccount' are null
 101      *
 102      * @param imageFile                 An {@link OCFile} to preview as an image in the fragment
 103      * @param ocAccount                 An ownCloud account; needed to start downloads
 104      * @param ignoreFirstSavedState     Flag to work around an unexpected behaviour of {@link FragmentStatePagerAdapter}; TODO better solution
 105      */
 106     public PreviewImageFragment(OCFile fileToDetail, Account ocAccount, boolean ignoreFirstSavedState) {
 107         super(fileToDetail);
 108         mAccount = ocAccount;
 109         mStorageManager = null; // we need a context to init this; the container activity is not available yet at this moment
 110         mIgnoreFirstSavedState = ignoreFirstSavedState;
 111     }
 112
 113
 114     /**
 115      *  Creates an empty fragment for image previews.
 116      *
 117      *  MUST BE KEPT: the system uses it when tries to reinstantiate a fragment automatically (for instance, when the device is turned a aside).
 118      *
 119      *  DO NOT CALL IT: an {@link OCFile} and {@link Account} must be provided for a successful construction
 120      */
 121     public PreviewImageFragment() {
 122         super();
 123         mAccount = null;
 124         mStorageManager = null;
 125         mIgnoreFirstSavedState = false;
 126     }
 127
 128
 129     /**
 130      * {@inheritDoc}
 131      */
 132     @Override
 133     public void onCreate(Bundle savedInstanceState) {
 134         super.onCreate(savedInstanceState);
 135         mHandler = new Handler();
 136         setHasOptionsMenu(true);
 137     }
 138
 139
 140     /**
 141      * {@inheritDoc}
 142      */
 143     @Override
 144     public View onCreateView(LayoutInflater inflater, ViewGroup container,
 145             Bundle savedInstanceState) {
 146         super.onCreateView(inflater, container, savedInstanceState);
 147         mView = inflater.inflate(R.layout.preview_image_fragment, container, false);
 148         mImageView = (ImageView)mView.findViewById(R.id.image);
 149         mImageView.setVisibility(View.GONE);
 150         mView.setOnTouchListener((OnTouchListener)getActivity());   // WATCH OUT THAT CAST
 151         mMessageView = (TextView)mView.findViewById(R.id.message);
 152         mMessageView.setVisibility(View.GONE);
 153         mProgressWheel = (ProgressBar)mView.findViewById(R.id.progressWheel);
 154         mProgressWheel.setVisibility(View.VISIBLE);
 155         return mView;
 156     }
 157
 158
 159     /**
 160      * {@inheritDoc}
 161      */
 162     @Override
 163     public void onAttach(Activity activity) {
 164         super.onAttach(activity);
 165         if (!(activity instanceof FileFragment.ContainerActivity))
 166             throw new ClassCastException(activity.toString() + " must implement " + FileFragment.ContainerActivity.class.getSimpleName());
 167     }
 168
 169
 170     /**
 171      * {@inheritDoc}
 172      */
 173     @Override
 174     public void onActivityCreated(Bundle savedInstanceState) {
 175         super.onActivityCreated(savedInstanceState);
 176         mStorageManager = new FileDataStorageManager(mAccount, getActivity().getApplicationContext().getContentResolver());
 177         if (savedInstanceState != null) {
 178             if (!mIgnoreFirstSavedState) {
 179                 OCFile file = (OCFile)savedInstanceState.getParcelable(PreviewImageFragment.EXTRA_FILE);
 180                 mAccount = savedInstanceState.getParcelable(PreviewImageFragment.EXTRA_ACCOUNT);
 181
 182                 // Update the file
 183                 if (mAccount!= null) {
 184                     mStorageManager = new FileDataStorageManager(mAccount, getActivity().getApplicationContext().getContentResolver());
 185                     OCFile updatedFile = mStorageManager.getFileByPath(file.getRemotePath());
 186                     if (updatedFile != null) {
 187                         setFile(updatedFile);
 188                     } else {
 189                         setFile(file);
 190                     }
 191                 } else {
 192                     setFile(file);
 193                 }
 194
 195             } else {
 196                 mIgnoreFirstSavedState = false;
 197             }
 198         }
 199         if (getFile() == null) {
 200             throw new IllegalStateException("Instanced with a NULL OCFile");
 201         }
 202         if (mAccount == null) {
 203             throw new IllegalStateException("Instanced with a NULL ownCloud Account");
 204         }
 205         if (!getFile().isDown()) {
 206             throw new IllegalStateException("There is no local file to preview");
 207         }
 208     }
 209
 210
 211     /**
 212      * {@inheritDoc}
 213      */
 214     @Override
 215     public void onSaveInstanceState(Bundle outState) {
 216         super.onSaveInstanceState(outState);
 217         outState.putParcelable(PreviewImageFragment.EXTRA_FILE, getFile());
 218         outState.putParcelable(PreviewImageFragment.EXTRA_ACCOUNT, mAccount);
 219     }
 220
 221
 222     @Override
 223     public void onStart() {
 224         super.onStart();
 225         if (getFile() != null) {
 226            BitmapLoader bl = new BitmapLoader(mImageView, mMessageView, mProgressWheel);
 227            bl.execute(new String[]{getFile().getStoragePath()});
 228         }
 229     }
 230
 231
 232     /**
 233      * {@inheritDoc}
 234      */
 235     @Override
 236     public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
 237         super.onCreateOptionsMenu(menu, inflater);
 238
 239         inflater.inflate(R.menu.file_actions_menu, menu);
 240         List<Integer> toHide = new ArrayList<Integer>();
 241
 242         MenuItem item = null;
 243         toHide.add(R.id.action_cancel_download);
 244         toHide.add(R.id.action_cancel_upload);
 245         toHide.add(R.id.action_download_file);
 246         toHide.add(R.id.action_rename_file);    // by now
 247
 248         // Options shareLink
 249         if (!getFile().isShareByLink()) {
 250             toHide.add(R.id.action_unshare_file);
 251         }
 252
 253         // Send file
 254         boolean sendEnabled = getString(R.string.send_files_to_other_apps).equalsIgnoreCase("on");
 255         if (!sendEnabled) {
 256             toHide.add(R.id.action_send_file);
 257         }
 258
 259         for (int i : toHide) {
 260             item = menu.findItem(i);
 261             if (item != null) {
 262                 item.setVisible(false);
 263                 item.setEnabled(false);
 264             }
 265         }
 266
 267     }
 268
 269     /**
 270      * {@inheritDoc}
 271      */
 272     @Override
 273     public void onPrepareOptionsMenu(Menu menu) {
 274         super.onPrepareOptionsMenu(menu);
 275
 276         MenuItem item = menu.findItem(R.id.action_unshare_file);
 277         // Options shareLink
 278         OCFile file = ((FileActivity) getSherlockActivity()).getFile();
 279         if (!file.isShareByLink()) {
 280             item.setVisible(false);
 281             item.setEnabled(false);
 282         } else {
 283             item.setVisible(true);
 284             item.setEnabled(true);
 285         }
 286
 287     }
 288
 289
 290
 291     /**
 292      * {@inheritDoc}
 293      */
 294     @Override
 295     public boolean onOptionsItemSelected(MenuItem item) {
 296         switch (item.getItemId()) {
 297             case R.id.action_share_file: {
 298                 FileActivity act = (FileActivity)getSherlockActivity();
 299                 act.getFileOperationsHelper().shareFileWithLink(getFile(), act);
 300                 return true;
 301             }
 302             case R.id.action_unshare_file: {
 303                 FileActivity act = (FileActivity)getSherlockActivity();
 304                 act.getFileOperationsHelper().unshareFileWithLink(getFile(), act);
 305                 return true;
 306             }
 307             case R.id.action_open_file_with: {
 308                 openFile();
 309                 return true;
 310             }
 311             case R.id.action_remove_file: {
 312                 removeFile();
 313                 return true;
 314             }
 315             case R.id.action_see_details: {
 316                 seeDetails();
 317                 return true;
 318             }
 319             case R.id.action_send_file: {
 320                 FileActivity act = (FileActivity)getSherlockActivity();
 321                 act.getFileOperationsHelper().sendDownloadedFile(getFile(), act);
 322                 return true;
 323             }
 324
 325             default:
 326                 return false;
 327         }
 328     }
 329
 330
 331     private void seeDetails() {
 332         ((FileFragment.ContainerActivity)getActivity()).showDetails(getFile());
 333     }
 334
 335
 336     @Override
 337     public void onResume() {
 338         super.onResume();
 339     }
 340
 341
 342     @Override
 343     public void onPause() {
 344         super.onPause();
 345     }
 346
 347
 348     @Override
 349     public void onDestroy() {
 350         super.onDestroy();
 351         if (mBitmap != null) {
 352             mBitmap.recycle();
 353         }
 354     }
 355
 356
 357     /**
 358      * Opens the previewed image with an external application.
 359      *
 360      * TODO - improve this; instead of prioritize the actions available for the MIME type in the server,
 361      * we should get a list of available apps for MIME tpye in the server and join it with the list of
 362      * available apps for the MIME type known from the file extension, to let the user choose
 363      */
 364     private void openFile() {
 365         OCFile file = getFile();
 366         String storagePath = file.getStoragePath();
 367         String encodedStoragePath = WebdavUtils.encodePath(storagePath);
 368         try {
 369             Intent i = new Intent(Intent.ACTION_VIEW);
 370             i.setDataAndType(Uri.parse("file://"+ encodedStoragePath), file.getMimetype());
 371             i.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
 372             startActivity(i);
 373
 374         } catch (Throwable t) {
 375             Log_OC.e(TAG, "Fail when trying to open with the mimeType provided from the ownCloud server: " + file.getMimetype());
 376             boolean toastIt = true;
 377             String mimeType = "";
 378             try {
 379                 Intent i = new Intent(Intent.ACTION_VIEW);
 380                 mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(storagePath.substring(storagePath.lastIndexOf('.') + 1));
 381                 if (mimeType == null || !mimeType.equals(file.getMimetype())) {
 382                     if (mimeType != null) {
 383                         i.setDataAndType(Uri.parse("file://"+ encodedStoragePath), mimeType);
 384                     } else {
 385                         // desperate try
 386                         i.setDataAndType(Uri.parse("file://"+ encodedStoragePath), "*-/*");
 387                     }
 388                     i.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
 389                     startActivity(i);
 390                     toastIt = false;
 391                 }
 392
 393             } catch (IndexOutOfBoundsException e) {
 394                 Log_OC.e(TAG, "Trying to find out MIME type of a file without extension: " + storagePath);
 395
 396             } catch (ActivityNotFoundException e) {
 397                 Log_OC.e(TAG, "No activity found to handle: " + storagePath + " with MIME type " + mimeType + " obtained from extension");
 398
 399             } catch (Throwable th) {
 400                 Log_OC.e(TAG, "Unexpected problem when opening: " + storagePath, th);
 401
 402             } finally {
 403                 if (toastIt) {
 404                     Toast.makeText(getActivity(), "There is no application to handle file " + file.getFileName(), Toast.LENGTH_SHORT).show();
 405                 }
 406             }
 407
 408         }
 409         finish();
 410     }
 411
 412
 413     /**
 414      * Starts a the removal of the previewed file.
 415      *
 416      * Shows a confirmation dialog. The action continues in {@link #onConfirmation(String)} , {@link #onNeutral(String)} or {@link #onCancel(String)},
 417      * depending upon the user selection in the dialog.
 418      */
 419     private void removeFile() {
 420         ConfirmationDialogFragment confDialog = ConfirmationDialogFragment.newInstance(
 421                 R.string.confirmation_remove_alert,
 422                 new String[]{getFile().getFileName()},
 423                 R.string.confirmation_remove_remote_and_local,
 424                 R.string.confirmation_remove_local,
 425                 R.string.common_cancel);
 426         confDialog.setOnConfirmationListener(this);
 427         confDialog.show(getFragmentManager(), ConfirmationDialogFragment.FTAG_CONFIRMATION);
 428     }
 429
 430
 431     /**
 432      * Performs the removal of the previewed file, both locally and in the server.
 433      */
 434     @Override
 435     public void onConfirmation(String callerTag) {
 436         if (mStorageManager.getFileById(getFile().getFileId()) != null) {   // check that the file is still there;
 437             mLastRemoteOperation = new RemoveFileOperation( getFile(),      // TODO we need to review the interface with RemoteOperations, and use OCFile IDs instead of OCFile objects as parameters
 438                                                             true,
 439                                                             mStorageManager);
 440             mLastRemoteOperation.execute(mAccount, getSherlockActivity(), this, mHandler, getSherlockActivity());
 441
 442             ((PreviewImageActivity) getActivity()).showLoadingDialog();
 443         }
 444     }
 445
 446
 447     /**
 448      * Removes the file from local storage
 449      */
 450     @Override
 451     public void onNeutral(String callerTag) {
 452         OCFile file = getFile();
 453         mStorageManager.removeFile(file, false, true);    // TODO perform in background task / new thread
 454         finish();
 455     }
 456
 457     /**
 458      * User cancelled the removal action.
 459      */
 460     @Override
 461     public void onCancel(String callerTag) {
 462         // nothing to do here
 463     }
 464
 465
 466     private class BitmapLoader extends AsyncTask<String, Void, Bitmap> {
 467
 468         /**
 469          * Weak reference to the target {@link ImageView} where the bitmap will be loaded into.
 470          *
 471          * Using a weak reference will avoid memory leaks if the target ImageView is retired from memory before the load finishes.
 472          */
 473         private final WeakReference<ImageView> mImageViewRef;
 474
 475         /**
 476          * Weak reference to the target {@link TextView} where error messages will be written.
 477          *
 478          * Using a weak reference will avoid memory leaks if the target ImageView is retired from memory before the load finishes.
 479          */
 480         private final WeakReference<TextView> mMessageViewRef;
 481
 482
 483         /**
 484          * Weak reference to the target {@link Progressbar} shown while the load is in progress.
 485          *
 486          * Using a weak reference will avoid memory leaks if the target ImageView is retired from memory before the load finishes.
 487          */
 488         private final WeakReference<ProgressBar> mProgressWheelRef;
 489
 490
 491         /**
 492          * Error message to show when a load fails
 493          */
 494         private int mErrorMessageId;
 495
 496
 497         /**
 498          * Constructor.
 499          *
 500          * @param imageView     Target {@link ImageView} where the bitmap will be loaded into.
 501          */
 502         public BitmapLoader(ImageView imageView, TextView messageView, ProgressBar progressWheel) {
 503             mImageViewRef = new WeakReference<ImageView>(imageView);
 504             mMessageViewRef = new WeakReference<TextView>(messageView);
 505             mProgressWheelRef = new WeakReference<ProgressBar>(progressWheel);
 506         }
 507
 508
 509         @SuppressWarnings("deprecation")
 510         @SuppressLint({ "NewApi", "NewApi", "NewApi" }) // to avoid Lint errors since Android SDK r20
 511                 @Override
 512         protected Bitmap doInBackground(String... params) {
 513             Bitmap result = null;
 514             if (params.length != 1) return result;
 515             String storagePath = params[0];
 516             try {
 517                 // set desired options that will affect the size of the bitmap
 518                 BitmapFactory.Options options = new Options();
 519                 options.inScaled = true;
 520                 options.inPurgeable = true;
 521                 if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.GINGERBREAD_MR1) {
 522                     options.inPreferQualityOverSpeed = false;
 523                 }
 524                 if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.HONEYCOMB) {
 525                     options.inMutable = false;
 526                 }
 527                 // make a false load of the bitmap - just to be able to read outWidth, outHeight and outMimeType
 528                 options.inJustDecodeBounds = true;
 529                 BitmapFactory.decodeFile(storagePath, options);
 530
 531                 int width = options.outWidth;
 532                 int height = options.outHeight;
 533                 int scale = 1;
 534
 535                 Display display = getActivity().getWindowManager().getDefaultDisplay();
 536                 Point size = new Point();
 537                 int screenWidth;
 538                 int screenHeight;
 539                 if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.HONEYCOMB_MR2) {
 540                     display.getSize(size);
 541                     screenWidth = size.x;
 542                     screenHeight = size.y;
 543                 } else {
 544                     screenWidth = display.getWidth();
 545                     screenHeight = display.getHeight();
 546                 }
 547
 548                 if (width > screenWidth) {
 549                     // second try to scale down the image , this time depending upon the screen size
 550                     scale = (int) Math.floor((float)width / screenWidth);
 551                 }
 552                 if (height > screenHeight) {
 553                     scale = Math.max(scale, (int) Math.floor((float)height / screenHeight));
 554                 }
 555                 options.inSampleSize = scale;
 556
 557                 // really load the bitmap
 558                 options.inJustDecodeBounds = false; // the next decodeFile call will be real
 559                 result = BitmapFactory.decodeFile(storagePath, options);
 560                 //Log_OC.d(TAG, "Image loaded - width: " + options.outWidth + ", loaded height: " + options.outHeight);
 561
 562                 if (result == null) {
 563                     mErrorMessageId = R.string.preview_image_error_unknown_format;
 564                     Log_OC.e(TAG, "File could not be loaded as a bitmap: " + storagePath);
 565                 }
 566
 567             } catch (OutOfMemoryError e) {
 568                 mErrorMessageId = R.string.preview_image_error_unknown_format;
 569                 Log_OC.e(TAG, "Out of memory occured for file " + storagePath, e);
 570
 571             } catch (NoSuchFieldError e) {
 572                 mErrorMessageId = R.string.common_error_unknown;
 573                 Log_OC.e(TAG, "Error from access to unexisting field despite protection; file " + storagePath, e);
 574
 575             } catch (Throwable t) {
 576                 mErrorMessageId = R.string.common_error_unknown;
 577                 Log_OC.e(TAG, "Unexpected error loading " + getFile().getStoragePath(), t);
 578
 579             }
 580             return result;
 581         }
 582
 583         @Override
 584         protected void onPostExecute(Bitmap result) {
 585             hideProgressWheel();
 586             if (result != null) {
 587                 showLoadedImage(result);
 588             } else {
 589                 showErrorMessage();
 590             }
 591         }
 592
 593         private void showLoadedImage(Bitmap result) {
 594             if (mImageViewRef != null) {
 595                 final ImageView imageView = mImageViewRef.get();
 596                 if (imageView != null) {
 597                     imageView.setImageBitmap(result);
 598                     imageView.setVisibility(View.VISIBLE);
 599                     mBitmap  = result;
 600                 } // else , silently finish, the fragment was destroyed
 601             }
 602             if (mMessageViewRef != null) {
 603                 final TextView messageView = mMessageViewRef.get();
 604                 if (messageView != null) {
 605                     messageView.setVisibility(View.GONE);
 606                 } // else , silently finish, the fragment was destroyed
 607             }
 608         }
 609
 610         private void showErrorMessage() {
 611             if (mImageViewRef != null) {
 612                 final ImageView imageView = mImageViewRef.get();
 613                 if (imageView != null) {
 614                     // shows the default error icon
 615                     imageView.setVisibility(View.VISIBLE);
 616                 } // else , silently finish, the fragment was destroyed
 617             }
 618             if (mMessageViewRef != null) {
 619                 final TextView messageView = mMessageViewRef.get();
 620                 if (messageView != null) {
 621                     messageView.setText(mErrorMessageId);
 622                     messageView.setVisibility(View.VISIBLE);
 623                 } // else , silently finish, the fragment was destroyed
 624             }
 625         }
 626
 627         private void hideProgressWheel() {
 628             if (mProgressWheelRef != null) {
 629                 final ProgressBar progressWheel = mProgressWheelRef.get();
 630                 if (progressWheel != null) {
 631                     progressWheel.setVisibility(View.GONE);
 632                 }
 633             }
 634         }
 635
 636     }
 637
 638     /**
 639      * Helper method to test if an {@link OCFile} can be passed to a {@link PreviewImageFragment} to be previewed.
 640      *
 641      * @param file      File to test if can be previewed.
 642      * @return          'True' if the file can be handled by the fragment.
 643      */
 644     public static boolean canBePreviewed(OCFile file) {
 645         return (file != null && file.isImage());
 646     }
 647
 648
 649     /**
 650      * {@inheritDoc}
 651      */
 652     @Override
 653     public void onRemoteOperationFinish(RemoteOperation operation, RemoteOperationResult result) {
 654         if (operation.equals(mLastRemoteOperation) && operation instanceof RemoveFileOperation) {
 655             onRemoveFileOperationFinish((RemoveFileOperation)operation, result);
 656         }
 657     }
 658
 659     private void onRemoveFileOperationFinish(RemoveFileOperation operation, RemoteOperationResult result) {
 660         ((PreviewImageActivity) getActivity()).dismissLoadingDialog();
 661
 662         if (result.isSuccess()) {
 663             Toast msg = Toast.makeText(getActivity().getApplicationContext(), R.string.remove_success_msg, Toast.LENGTH_LONG);
 664             msg.show();
 665             finish();
 666
 667         } else {
 668             Toast msg = Toast.makeText(getActivity(), R.string.remove_fail_msg, Toast.LENGTH_LONG);
 669             msg.show();
 670             if (result.isSslRecoverableException()) {
 671                 // TODO show the SSL warning dialog
 672             }
 673         }
 674     }
 675
 676     /**
 677      * Finishes the preview
 678      */
 679     private void finish() {
 680         Activity container = getActivity();
 681         container.finish();
 682     }
 683
 684
 685 }