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

   1 /**
   2  *   ownCloud Android client application
   3  *
   4  *   @author David A. Velasco
   5  *   Copyright (C) 2015 ownCloud Inc.
   6  *
   7  *   This program is free software: you can redistribute it and/or modify
   8  *   it under the terms of the GNU General Public License version 2,
   9  *   as published by the Free Software Foundation.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20 package com.owncloud.android.ui.preview;
  21
  22 import java.lang.ref.WeakReference;
  23
  24 import android.accounts.Account;
  25 import android.annotation.SuppressLint;
  26 import android.app.Activity;
  27 import android.graphics.Bitmap;
  28 import android.graphics.Point;
  29 import android.os.AsyncTask;
  30 import android.os.Bundle;
  31 import android.support.v4.app.FragmentStatePagerAdapter;
  32 import android.view.LayoutInflater;
  33 import android.view.Menu;
  34 import android.view.MenuInflater;
  35 import android.view.MenuItem;
  36 import android.view.View;
  37 import android.view.View.OnClickListener;
  38 import android.view.ViewGroup;
  39 import android.widget.ImageView;
  40 import android.widget.ProgressBar;
  41 import android.widget.TextView;
  42
  43 import com.owncloud.android.R;
  44 import com.owncloud.android.datamodel.OCFile;
  45 import com.owncloud.android.files.FileMenuFilter;
  46 import com.owncloud.android.lib.common.utils.Log_OC;
  47 import com.owncloud.android.ui.dialog.ConfirmationDialogFragment;
  48 import com.owncloud.android.ui.dialog.RemoveFileDialogFragment;
  49 import com.owncloud.android.ui.fragment.FileFragment;
  50 import com.owncloud.android.utils.BitmapUtils;
  51 import com.owncloud.android.utils.DisplayUtils;
  52
  53 import third_parties.michaelOrtiz.TouchImageViewCustom;
  54
  55
  56 /**
  57  * This fragment shows a preview of a downloaded image.
  58  *
  59  * Trying to get an instance with a NULL {@link OCFile} will produce an
  60  * {@link IllegalStateException}.
  61  *
  62  * If the {@link OCFile} passed is not downloaded, an {@link IllegalStateException} is generated on
  63  * instantiation too.
  64  */
  65 public class PreviewImageFragment extends FileFragment {
  66
  67     public static final String EXTRA_FILE = "FILE";
  68
  69     private static final String ARG_FILE = "FILE";
  70     private static final String ARG_IGNORE_FIRST = "IGNORE_FIRST";
  71
  72     private TouchImageViewCustom mImageView;
  73     private TextView mMessageView;
  74     private ProgressBar mProgressWheel;
  75
  76     public Bitmap mBitmap = null;
  77
  78     private static final String TAG = PreviewImageFragment.class.getSimpleName();
  79
  80     private boolean mIgnoreFirstSavedState;
  81
  82     private LoadBitmapTask mLoadBitmapTask = null;
  83
  84
  85     /**
  86      * Public factory method to create a new fragment that previews an image.
  87      *
  88      * Android strongly recommends keep the empty constructor of fragments as the only public
  89      * constructor, and
  90      * use {@link #setArguments(Bundle)} to set the needed arguments.
  91      *
  92      * This method hides to client objects the need of doing the construction in two steps.
  93      *
  94      * @param imageFile                 An {@link OCFile} to preview as an image in the fragment
  95      * @param ignoreFirstSavedState     Flag to work around an unexpected behaviour of
  96      *                                  {@link FragmentStatePagerAdapter}
  97      *                                  ; TODO better solution
  98      */
  99     public static PreviewImageFragment newInstance(OCFile imageFile, boolean ignoreFirstSavedState){
 100         PreviewImageFragment frag = new PreviewImageFragment();
 101         Bundle args = new Bundle();
 102         args.putParcelable(ARG_FILE, imageFile);
 103         args.putBoolean(ARG_IGNORE_FIRST, ignoreFirstSavedState);
 104         frag.setArguments(args);
 105         return frag;
 106     }
 107
 108
 109
 110     /**
 111      *  Creates an empty fragment for image previews.
 112      *
 113      *  MUST BE KEPT: the system uses it when tries to reinstantiate a fragment automatically
 114      *  (for instance, when the device is turned a aside).
 115      *
 116      *  DO NOT CALL IT: an {@link OCFile} and {@link Account} must be provided for a successful
 117      *  construction
 118      */
 119     public PreviewImageFragment() {
 120         mIgnoreFirstSavedState = false;
 121     }
 122
 123
 124     /**
 125      * {@inheritDoc}
 126      */
 127     @Override
 128     public void onCreate(Bundle savedInstanceState) {
 129         super.onCreate(savedInstanceState);
 130         Bundle args = getArguments();
 131         setFile((OCFile)args.getParcelable(ARG_FILE));
 132             // TODO better in super, but needs to check ALL the class extending FileFragment;
 133             // not right now
 134
 135         mIgnoreFirstSavedState = args.getBoolean(ARG_IGNORE_FIRST);
 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         View view = inflater.inflate(R.layout.preview_image_fragment, container, false);
 148         mImageView = (TouchImageViewCustom) view.findViewById(R.id.image);
 149         mImageView.setVisibility(View.GONE);
 150         mImageView.setOnClickListener(new OnClickListener() {
 151             @Override
 152             public void onClick(View v) {
 153                 ((PreviewImageActivity) getActivity()).toggleFullScreen();
 154             }
 155
 156         });
 157         mMessageView = (TextView)view.findViewById(R.id.message);
 158         mMessageView.setVisibility(View.GONE);
 159         mProgressWheel = (ProgressBar)view.findViewById(R.id.progressWheel);
 160         mProgressWheel.setVisibility(View.VISIBLE);
 161         return view;
 162     }
 163
 164     /**
 165      * {@inheritDoc}
 166      */
 167     @Override
 168     public void onActivityCreated(Bundle savedInstanceState) {
 169         super.onActivityCreated(savedInstanceState);
 170         if (savedInstanceState != null) {
 171             if (!mIgnoreFirstSavedState) {
 172                 OCFile file = savedInstanceState.getParcelable(PreviewImageFragment.EXTRA_FILE);
 173                 setFile(file);
 174             } else {
 175                 mIgnoreFirstSavedState = false;
 176             }
 177         }
 178         if (getFile() == null) {
 179             throw new IllegalStateException("Instanced with a NULL OCFile");
 180         }
 181         if (!getFile().isDown()) {
 182             throw new IllegalStateException("There is no local file to preview");
 183         }
 184     }
 185
 186
 187     /**
 188      * {@inheritDoc}
 189      */
 190     @Override
 191     public void onSaveInstanceState(Bundle outState) {
 192         super.onSaveInstanceState(outState);
 193         outState.putParcelable(PreviewImageFragment.EXTRA_FILE, getFile());
 194     }
 195
 196
 197     @Override
 198     public void onStart() {
 199         super.onStart();
 200         if (getFile() != null) {
 201             mLoadBitmapTask = new LoadBitmapTask(mImageView, mMessageView, mProgressWheel);
 202             //mLoadBitmapTask.execute(new String[]{getFile().getStoragePath()});
 203             mLoadBitmapTask.execute(getFile().getStoragePath());
 204         }
 205     }
 206
 207
 208     @Override
 209     public void onStop() {
 210         Log_OC.d(TAG, "onStop starts");
 211         if (mLoadBitmapTask != null) {
 212             mLoadBitmapTask.cancel(true);
 213             mLoadBitmapTask = null;
 214         }
 215         super.onStop();
 216     }
 217
 218     /**
 219      * {@inheritDoc}
 220      */
 221     @Override
 222     public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
 223         super.onCreateOptionsMenu(menu, inflater);
 224         inflater.inflate(R.menu.file_actions_menu, menu);
 225     }
 226
 227     /**
 228      * {@inheritDoc}
 229      */
 230     @Override
 231     public void onPrepareOptionsMenu(Menu menu) {
 232         super.onPrepareOptionsMenu(menu);
 233
 234         if (mContainerActivity.getStorageManager() != null) {
 235             // Update the file
 236             setFile(mContainerActivity.getStorageManager().getFileById(getFile().getFileId()));
 237
 238             FileMenuFilter mf = new FileMenuFilter(
 239                 getFile(),
 240                 mContainerActivity.getStorageManager().getAccount(),
 241                 mContainerActivity,
 242                 getActivity()
 243             );
 244             mf.filter(menu);
 245         }
 246
 247         // additional restriction for this fragment
 248         // TODO allow renaming in PreviewImageFragment
 249         MenuItem item = menu.findItem(R.id.action_rename_file);
 250         if (item != null) {
 251             item.setVisible(false);
 252             item.setEnabled(false);
 253         }
 254
 255         // additional restriction for this fragment
 256         // TODO allow refresh file in PreviewImageFragment
 257         item = menu.findItem(R.id.action_sync_file);
 258         if (item != null) {
 259             item.setVisible(false);
 260             item.setEnabled(false);
 261         }
 262
 263         // additional restriction for this fragment
 264         item = menu.findItem(R.id.action_move);
 265         if (item != null) {
 266             item.setVisible(false);
 267             item.setEnabled(false);
 268         }
 269
 270     }
 271
 272
 273
 274     /**
 275      * {@inheritDoc}
 276      */
 277     @Override
 278     public boolean onOptionsItemSelected(MenuItem item) {
 279         switch (item.getItemId()) {
 280             case R.id.action_share_file: {
 281                 mContainerActivity.getFileOperationsHelper().shareFileWithLink(getFile());
 282                 return true;
 283             }
 284             case R.id.action_unshare_file: {
 285                 mContainerActivity.getFileOperationsHelper().unshareFileWithLink(getFile());
 286                 return true;
 287             }
 288             case R.id.action_open_file_with: {
 289                 openFile();
 290                 return true;
 291             }
 292             case R.id.action_remove_file: {
 293                 RemoveFileDialogFragment dialog = RemoveFileDialogFragment.newInstance(getFile());
 294                 dialog.show(getFragmentManager(), ConfirmationDialogFragment.FTAG_CONFIRMATION);
 295                 return true;
 296             }
 297             case R.id.action_see_details: {
 298                 seeDetails();
 299                 return true;
 300             }
 301             case R.id.action_send_file: {
 302                 mContainerActivity.getFileOperationsHelper().sendDownloadedFile(getFile());
 303                 return true;
 304             }
 305             case R.id.action_sync_file: {
 306                 mContainerActivity.getFileOperationsHelper().syncFile(getFile());
 307                 return true;
 308             }
 309
 310             default:
 311                 return false;
 312         }
 313     }
 314
 315
 316     private void seeDetails() {
 317         mContainerActivity.showDetails(getFile());
 318     }
 319
 320
 321     @Override
 322     public void onResume() {
 323         super.onResume();
 324     }
 325
 326
 327     @Override
 328     public void onPause() {
 329         super.onPause();
 330     }
 331
 332     @Override
 333     public void onDestroy() {
 334         if (mBitmap != null) {
 335             mBitmap.recycle();
 336             System.gc();
 337                 // putting this in onStop() is just the same; the fragment is always destroyed by
 338                 // {@link FragmentStatePagerAdapter} when the fragment in swiped further than the
 339                 // valid offscreen distance, and onStop() is never called before than that
 340         }
 341         super.onDestroy();
 342     }
 343
 344
 345     /**
 346      * Opens the previewed image with an external application.
 347      */
 348     private void openFile() {
 349         mContainerActivity.getFileOperationsHelper().openFile(getFile());
 350         finish();
 351     }
 352
 353
 354     private class LoadBitmapTask extends AsyncTask<String, Void, Bitmap> {
 355
 356         /**
 357          * Weak reference to the target {@link ImageView} where the bitmap will be loaded into.
 358          *
 359          * Using a weak reference will avoid memory leaks if the target ImageView is retired from
 360          * memory before the load finishes.
 361          */
 362         private final WeakReference<ImageViewCustom> mImageViewRef;
 363
 364         /**
 365          * Weak reference to the target {@link TextView} where error messages will be written.
 366          *
 367          * Using a weak reference will avoid memory leaks if the target ImageView is retired from
 368          * memory before the load finishes.
 369          */
 370         private final WeakReference<TextView> mMessageViewRef;
 371
 372
 373         /**
 374          * Weak reference to the target {@link ProgressBar} shown while the load is in progress.
 375          *
 376          * Using a weak reference will avoid memory leaks if the target ImageView is retired from
 377          * memory before the load finishes.
 378          */
 379         private final WeakReference<ProgressBar> mProgressWheelRef;
 380
 381
 382         /**
 383          * Error message to show when a load fails
 384          */
 385         private int mErrorMessageId;
 386
 387
 388         /**
 389          * Constructor.
 390          *
 391          * @param imageView     Target {@link ImageView} where the bitmap will be loaded into.
 392          */
 393         public LoadBitmapTask(ImageViewCustom imageView, TextView messageView,
 394                               ProgressBar progressWheel) {
 395             mImageViewRef = new WeakReference<ImageViewCustom>(imageView);
 396             mMessageViewRef = new WeakReference<TextView>(messageView);
 397             mProgressWheelRef = new WeakReference<ProgressBar>(progressWheel);
 398         }
 399
 400
 401         @Override
 402         protected Bitmap doInBackground(String... params) {
 403             Bitmap result = null;
 404             if (params.length != 1) return null;
 405             String storagePath = params[0];
 406             try {
 407
 408                 int maxDownScale = 3;   // could be a parameter passed to doInBackground(...)
 409                 Point screenSize = DisplayUtils.getScreenSize(getActivity());
 410                 int minWidth = screenSize.x;
 411                 int minHeight = screenSize.y;
 412                 for (int i = 0; i < maxDownScale && result == null; i++) {
 413                     if (isCancelled()) return null;
 414                     try {
 415                         result = BitmapUtils.decodeSampledBitmapFromFile(storagePath, minWidth,
 416                                 minHeight);
 417
 418                         if (isCancelled()) return result;
 419
 420                         if (result == null) {
 421                             mErrorMessageId = R.string.preview_image_error_unknown_format;
 422                             Log_OC.e(TAG, "File could not be loaded as a bitmap: " + storagePath);
 423                             break;
 424                         } else {
 425                             // Rotate image, obeying exif tag.
 426                             result = BitmapUtils.rotateImage(result, storagePath);
 427                         }
 428
 429                     } catch (OutOfMemoryError e) {
 430                         mErrorMessageId = R.string.common_error_out_memory;
 431                         if (i < maxDownScale - 1) {
 432                             Log_OC.w(TAG, "Out of memory rendering file " + storagePath +
 433                                     " ; scaling down");
 434                             minWidth = minWidth / 2;
 435                             minHeight = minHeight / 2;
 436
 437                         } else {
 438                             Log_OC.w(TAG, "Out of memory rendering file " + storagePath +
 439                                     " ; failing");
 440                         }
 441                         if (result != null) {
 442                             result.recycle();
 443                         }
 444                         result = null;
 445                     }
 446                 }
 447
 448             } catch (NoSuchFieldError e) {
 449                 mErrorMessageId = R.string.common_error_unknown;
 450                 Log_OC.e(TAG, "Error from access to unexisting field despite protection; file "
 451                                 + storagePath, e);
 452
 453             } catch (Throwable t) {
 454                 mErrorMessageId = R.string.common_error_unknown;
 455                 Log_OC.e(TAG, "Unexpected error loading " + getFile().getStoragePath(), t);
 456
 457             }
 458
 459             return result;
 460         }
 461
 462         @Override
 463         protected void onCancelled(Bitmap result) {
 464             if (result != null) {
 465                 result.recycle();
 466             }
 467         }
 468
 469         @Override
 470         protected void onPostExecute(Bitmap result) {
 471             hideProgressWheel();
 472             if (result != null) {
 473                 showLoadedImage(result);
 474             } else {
 475                 showErrorMessage();
 476             }
 477             if (result != null && mBitmap != result)  {
 478                 // unused bitmap, release it! (just in case)
 479                 result.recycle();
 480             }
 481         }
 482
 483         @SuppressLint("InlinedApi")
 484         private void showLoadedImage(Bitmap result) {
 485             final ImageViewCustom imageView = mImageViewRef.get();
 486             if (imageView != null) {
 487                 Log_OC.d(TAG, "Showing image with resolution " + result.getWidth() + "x" +
 488                         result.getHeight());
 489                 imageView.setImageBitmap(result);
 490                 imageView.setVisibility(View.VISIBLE);
 491                 mBitmap  = result;  // needs to be kept for recycling when not useful
 492             }
 493
 494             final TextView messageView = mMessageViewRef.get();
 495             if (messageView != null) {
 496                 messageView.setVisibility(View.GONE);
 497             } // else , silently finish, the fragment was destroyed
 498         }
 499
 500         private void showErrorMessage() {
 501             final ImageView imageView = mImageViewRef.get();
 502             if (imageView != null) {
 503                 // shows the default error icon
 504                 imageView.setVisibility(View.VISIBLE);
 505             } // else , silently finish, the fragment was destroyed
 506
 507             final TextView messageView = mMessageViewRef.get();
 508             if (messageView != null) {
 509                 messageView.setText(mErrorMessageId);
 510                 messageView.setVisibility(View.VISIBLE);
 511             } // else , silently finish, the fragment was destroyed
 512         }
 513
 514         private void hideProgressWheel() {
 515             final ProgressBar progressWheel = mProgressWheelRef.get();
 516             if (progressWheel != null) {
 517                 progressWheel.setVisibility(View.GONE);
 518             }
 519         }
 520
 521     }
 522
 523     /**
 524      * Helper method to test if an {@link OCFile} can be passed to a {@link PreviewImageFragment}
 525      * to be previewed.
 526      *
 527      * @param file      File to test if can be previewed.
 528      * @return          'True' if the file can be handled by the fragment.
 529      */
 530     public static boolean canBePreviewed(OCFile file) {
 531         return (file != null && file.isImage());
 532     }
 533
 534
 535     /**
 536      * Finishes the preview
 537      */
 538     private void finish() {
 539         Activity container = getActivity();
 540         container.finish();
 541     }
 542
 543     public TouchImageViewCustom getImageView() {
 544         return mImageView;
 545     }
 546
 547 }