app/src/main/java/com/stoutner/privacybrowser/activities/BookmarksActivity.java

   1 /*
   2  * Copyright © 2016-2017 Soren Stoutner <soren@stoutner.com>.
   3  *
   4  * This file is part of Privacy Browser <https://www.stoutner.com/privacy-browser>.
   5  *
   6  * Privacy Browser is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * Privacy Browser 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 Privacy Browser.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 package com.stoutner.privacybrowser.activities;
  21
  22 import android.app.Activity;
  23 import android.content.Context;
  24 import android.content.Intent;
  25 import android.database.Cursor;
  26 import android.graphics.Bitmap;
  27 import android.graphics.BitmapFactory;
  28 import android.graphics.Typeface;
  29 import android.graphics.drawable.BitmapDrawable;
  30 import android.graphics.drawable.Drawable;
  31 import android.os.Bundle;
  32 import android.support.design.widget.FloatingActionButton;
  33 import android.support.design.widget.Snackbar;
  34 import android.support.v4.app.NavUtils;
  35 import android.support.v7.app.ActionBar;
  36 import android.support.v7.app.AppCompatActivity;
  37 import android.support.v7.app.AppCompatDialogFragment;
  38 import android.support.v7.widget.Toolbar;
  39 import android.util.SparseBooleanArray;
  40 import android.view.ActionMode;
  41 import android.view.Menu;
  42 import android.view.MenuItem;
  43 import android.view.View;
  44 import android.view.ViewGroup;
  45 import android.widget.AbsListView;
  46 import android.widget.AdapterView;
  47 import android.widget.CursorAdapter;
  48 import android.widget.EditText;
  49 import android.widget.ImageView;
  50 import android.widget.ListView;
  51 import android.widget.RadioButton;
  52 import android.widget.TextView;
  53
  54 import com.stoutner.privacybrowser.dialogs.CreateBookmarkDialog;
  55 import com.stoutner.privacybrowser.dialogs.CreateBookmarkFolderDialog;
  56 import com.stoutner.privacybrowser.dialogs.EditBookmarkDialog;
  57 import com.stoutner.privacybrowser.dialogs.EditBookmarkFolderDialog;
  58 import com.stoutner.privacybrowser.dialogs.MoveToFolderDialog;
  59 import com.stoutner.privacybrowser.R;
  60 import com.stoutner.privacybrowser.helpers.BookmarksDatabaseHelper;
  61
  62 import java.io.ByteArrayOutputStream;
  63
  64 public class BookmarksActivity extends AppCompatActivity implements CreateBookmarkDialog.CreateBookmarkListener, CreateBookmarkFolderDialog.CreateBookmarkFolderListener, EditBookmarkDialog.EditBookmarkListener,
  65         EditBookmarkFolderDialog.EditBookmarkFolderListener, MoveToFolderDialog.MoveToFolderListener {
  66
  67     // `bookmarksDatabaseHelper` is public static so it can be accessed from `CreateBookmarkFolderDialog`, `EditBookmarkDialog`, `EditBookmarkFolderDialog` and `MoveToFolderDialog`.  It is also used in `onCreate()`, `onOptionsItemSelected()`,
  68     // `onBackPressed()`, `onCreateBookmark()`, `onCreateBookmarkFolder()`, `onSaveEditBookmark()`, `onSaveEditBookmarkFolder()`, `onMoveToFolder()`, `deleteBookmarkFolderContents()`, and `loadFolder().
  69     public static BookmarksDatabaseHelper bookmarksDatabaseHelper;
  70
  71     // `currentFolder` is public static so it can be accessed from `MoveToFolderDialog`.
  72     // It is used in `onCreate`, `onOptionsItemSelected()`, `onBackPressed()`, `onCreateBookmark()`, `onCreateBookmarkFolder()`, `onSaveEditBookmark()`, `onSaveEditBookmarkFolder()`, `onMoveToFolder()`, and `loadFolder()`.
  73     public static String currentFolder;
  74
  75     // `checkedItemIds` is public static so it can be accessed from `EditBookmarkDialog`, `EditBookmarkFolderDialog`, and `MoveToFolderDialog`.
  76     // It is also used in `onCreate()`, `onSaveEditBookmark()`, `onSaveEditBookmarkFolder()`, `onMoveToFolder()`, and `updateMoveIcons()`.
  77     public static long[] checkedItemIds;
  78
  79
  80     // `bookmarksListView` is used in `onCreate()`, `onOptionsItemSelected()`, `onCreateBookmark()`, `onCreateBookmarkFolder()`, `onSaveEditBookmark()`, `onSaveEditBookmarkFolder()`, `onMoveToFolder()`, `updateMoveIcons()`, `scrollBookmarks()`,
  81     // and `loadFolder()`.
  82     private ListView bookmarksListView;
  83
  84     // `bookmarksCursor` is used in `onCreate()`, `onCreateBookmark()`, `onCreateBookmarkFolder()`, `onSaveEditBookmark()`, `onSaveEditBookmarkFolder()`, `onMoveToFolder()`, `deleteBookmarkFolderContents()`, and `loadFolder()`.
  85     private Cursor bookmarksCursor;
  86
  87     // `bookmarksCursorAdapter` is used in `onCreate(), `onCreateBookmark()`, `onCreateBookmarkFolder()`, `onSaveEditBookmark()`, `onSaveEditBookmarkFolder()`, `onMoveToFolder()`, and `onLoadFolder()`.
  88     private CursorAdapter bookmarksCursorAdapter;
  89
  90     // `contextualActionMode` is used in `onCreate()`, `onSaveEditBookmark()`, `onSaveEditBookmarkFolder()` and `onMoveToFolder()`.
  91     private ActionMode contextualActionMode;
  92
  93     // `appBar` is used in `onCreate()` and `loadFolder()`.
  94     private ActionBar appBar;
  95
  96     // `oldFolderName` is used in `onCreate()` and `onSaveEditBookmarkFolder()`.
  97     private String oldFolderNameString;
  98
  99     // `moveBookmarkUpMenuItem` is used in `onCreate()` and `updateMoveIcons`.
 100     private MenuItem moveBookmarkUpMenuItem;
 101
 102     // `moveBookmarkDownMenuItem` is used in `onCreate()` and `updateMoveIcons`.
 103     private MenuItem moveBookmarkDownMenuItem;
 104
 105     @Override
 106     protected void onCreate(Bundle savedInstanceState) {
 107         // Set the activity theme.
 108         if (MainWebViewActivity.darkTheme) {
 109             setTheme(R.style.PrivacyBrowserDark_SecondaryActivity);
 110         } else {
 111             setTheme(R.style.PrivacyBrowserLight_SecondaryActivity);
 112         }
 113
 114         // Run the default commands.
 115         super.onCreate(savedInstanceState);
 116
 117         // Set the content view.
 118         setContentView(R.layout.bookmarks_coordinatorlayout);
 119
 120         // Use the `SupportActionBar` from `android.support.v7.app.ActionBar` until the minimum API is >= 21.
 121         final Toolbar bookmarksAppBar = (Toolbar) findViewById(R.id.bookmarks_toolbar);
 122         setSupportActionBar(bookmarksAppBar);
 123
 124         // Get a handle for the activity, the app bar, and the `ListView`.
 125         final Activity bookmarksActivity = this;
 126         appBar = getSupportActionBar();
 127         bookmarksListView = (ListView) findViewById(R.id.bookmarks_listview);
 128
 129         // This assert removes the incorrect warning in Android Studio on the following line that `appBar` might be null.
 130         assert appBar != null;
 131
 132         // Display the home arrow on `SupportActionBar`.
 133         appBar.setDisplayHomeAsUpEnabled(true);
 134
 135         // Initialize the database helper and the `ListView`.  `this` specifies the context.  The two `nulls` do not specify the database name or a `CursorFactory`.
 136         // The `0` specifies a database version, but that is ignored and set instead using a constant in `BookmarksDatabaseHelper`.
 137         bookmarksDatabaseHelper = new BookmarksDatabaseHelper(this, null, null, 0);
 138
 139         // Set currentFolder to the home folder, which is `""` in the database.
 140         currentFolder = "";
 141
 142         // Load the home folder.
 143         loadFolder();
 144
 145         // Set a listener so that tapping a list item loads the URL or folder.
 146         bookmarksListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
 147             @Override
 148             public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
 149                 // Convert the id from long to int to match the format of the bookmarks database.
 150                 int databaseID = (int) id;
 151
 152                 // Get the bookmark `Cursor` for this ID and move it to the first row.
 153                 Cursor bookmarkCursor = bookmarksDatabaseHelper.getBookmarkCursor(databaseID);
 154                 bookmarkCursor.moveToFirst();
 155
 156                 // Act upon the bookmark according to the type.
 157                 if (bookmarkCursor.getInt(bookmarkCursor.getColumnIndex(BookmarksDatabaseHelper.IS_FOLDER)) == 1) {  // The selected bookmark is a folder.
 158                     // Update `currentFolder`.
 159                     currentFolder = bookmarkCursor.getString(bookmarkCursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_NAME));
 160
 161                     // Load the new folder.
 162                     loadFolder();
 163                 } else {  // The selected bookmark is not a folder.
 164                     // Get the bookmark URL and assign it to `formattedUrlString`.  `mainWebView` will automatically reload when `BookmarksActivity` closes.
 165                     MainWebViewActivity.formattedUrlString = bookmarkCursor.getString(bookmarkCursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_URL));
 166
 167                     // Return to `MainWebViewActivity`.
 168                     NavUtils.navigateUpFromSameTask(bookmarksActivity);
 169                 }
 170
 171                 // Close the `Cursor`.
 172                 bookmarkCursor.close();
 173             }
 174         });
 175
 176         // `MultiChoiceModeListener` handles long clicks.
 177         bookmarksListView.setMultiChoiceModeListener(new AbsListView.MultiChoiceModeListener() {
 178             // Instantiate the common variables.
 179             MenuItem editBookmarkMenuItem;
 180             MenuItem selectAllBookmarksMenuItem;
 181
 182             @Override
 183             public boolean onCreateActionMode(ActionMode mode, Menu menu) {
 184                 // Inflate the menu for the contextual app bar and set the title.
 185                 getMenuInflater().inflate(R.menu.bookmarks_context_menu, menu);
 186
 187                 // Set the title.
 188                 if (currentFolder.isEmpty()) {
 189                     // Use `R.string.bookmarks` if we are in the home folder.
 190                     mode.setTitle(R.string.bookmarks);
 191                 } else {  // Use the current folder name as the title.
 192                     mode.setTitle(currentFolder);
 193                 }
 194
 195                 // Get a handle for `MenuItems` that need to be selectively disabled.
 196                 moveBookmarkUpMenuItem = menu.findItem(R.id.move_bookmark_up);
 197                 moveBookmarkDownMenuItem = menu.findItem(R.id.move_bookmark_down);
 198                 editBookmarkMenuItem = menu.findItem(R.id.edit_bookmark);
 199                 selectAllBookmarksMenuItem = menu.findItem(R.id.context_menu_select_all_bookmarks);
 200
 201                 // Store `contextualActionMode` so it can be closed programatically.
 202                 contextualActionMode = mode;
 203
 204                 // Make it so.
 205                 return true;
 206             }
 207
 208             @Override
 209             public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
 210                 // Get a handle for the move to folder menu item.
 211                 MenuItem moveToFolderMenuItem = menu.findItem(R.id.move_to_folder);
 212
 213                 // Get a `Cursor` with all of the folders.
 214                 Cursor folderCursor = bookmarksDatabaseHelper.getAllFoldersCursor();
 215
 216                 // Enable the move to folder menu item if at least one folder exists.
 217                 moveToFolderMenuItem.setVisible(folderCursor.getCount() > 0);
 218
 219                 // Make it so.
 220                 return true;
 221             }
 222
 223             @Override
 224             public void onItemCheckedStateChanged(ActionMode mode, int position, long id, boolean checked) {
 225                 // Get a long array of the selected bookmarks.
 226                 long[] selectedBookmarksLongArray = bookmarksListView.getCheckedItemIds();
 227
 228                 // Calculate the number of selected bookmarks.
 229                 int numberOfSelectedBookmarks = selectedBookmarksLongArray.length;
 230
 231                 // Adjust the `ActionMode` and the `Menu` according to the number of selected bookmarks.
 232                 if (numberOfSelectedBookmarks == 0) {  // No bookmarks are selected.
 233                     // Close the `ActionMode`.
 234                     mode.finish();
 235                 } else if (numberOfSelectedBookmarks == 1) {  // One bookmark is selected.
 236                     // List the number of selected bookmarks in the subtitle.
 237                     mode.setSubtitle(getString(R.string.one_selected));
 238
 239                     // Show the `Move Up`, `Move Down`, and  `Edit` options.
 240                     moveBookmarkUpMenuItem.setVisible(true);
 241                     moveBookmarkDownMenuItem.setVisible(true);
 242                     editBookmarkMenuItem.setVisible(true);
 243
 244                     // Update the enabled status of the move icons.
 245                     updateMoveIcons();
 246                 } else {  // More than one bookmark is selected.
 247                     // List the number of selected bookmarks in the subtitle.
 248                     mode.setSubtitle(numberOfSelectedBookmarks + " " + getString(R.string.selected));
 249
 250                     // Hide non-applicable `MenuItems`.
 251                     moveBookmarkUpMenuItem.setVisible(false);
 252                     moveBookmarkDownMenuItem.setVisible(false);
 253                     editBookmarkMenuItem.setVisible(false);
 254                 }
 255
 256                 // Do not show `Select All` if all the bookmarks are already checked.
 257                 if (bookmarksListView.getCheckedItemIds().length == bookmarksListView.getCount()) {
 258                     selectAllBookmarksMenuItem.setVisible(false);
 259                 } else {
 260                     selectAllBookmarksMenuItem.setVisible(true);
 261                 }
 262             }
 263
 264             @Override
 265             public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
 266                 // Get the menu item ID.
 267                 int menuItemId = item.getItemId();
 268
 269                 // Instantiate the common variables.
 270                 int selectedBookmarkPosition;
 271                 int selectedBookmarkNewPosition;
 272                 final SparseBooleanArray selectedBookmarksPositionsSparseBooleanArray;
 273
 274                 switch (menuItemId) {
 275                     case R.id.move_bookmark_up:
 276                         // Get the array of checked bookmark positions.
 277                         selectedBookmarksPositionsSparseBooleanArray = bookmarksListView.getCheckedItemPositions();
 278
 279                         // Store the position of the selected bookmark.  Only one bookmark is selected when `move_bookmark_up` is enabled.
 280                         selectedBookmarkPosition = selectedBookmarksPositionsSparseBooleanArray.keyAt(0);
 281
 282                         // Calculate the new position of the selected bookmark.
 283                         selectedBookmarkNewPosition = selectedBookmarkPosition - 1;
 284
 285                         // Iterate through the bookmarks.
 286                         for (int i = 0; i < bookmarksListView.getCount(); i++) {
 287                             // Get the database ID for the current bookmark.
 288                             int currentBookmarkDatabaseId = (int) bookmarksListView.getItemIdAtPosition(i);
 289
 290                             // Update the display order for the current bookmark.
 291                             if (i == selectedBookmarkPosition) {  // The current bookmark is the selected bookmark.
 292                                 // Move the current bookmark up one.
 293                                 bookmarksDatabaseHelper.updateDisplayOrder(currentBookmarkDatabaseId, i - 1);
 294                             } else if ((i + 1) == selectedBookmarkPosition){  // The current bookmark is immediately above the selected bookmark.
 295                                 // Move the current bookmark down one.
 296                                 bookmarksDatabaseHelper.updateDisplayOrder(currentBookmarkDatabaseId, i + 1);
 297                             } else {  // The current bookmark is not changing positions.
 298                                 // Move `bookmarksCursor` to the current bookmark position.
 299                                 bookmarksCursor.moveToPosition(i);
 300
 301                                 // Update the display order only if it is not correct in the database.
 302                                 if (bookmarksCursor.getInt(bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper.DISPLAY_ORDER)) != i) {
 303                                     bookmarksDatabaseHelper.updateDisplayOrder(currentBookmarkDatabaseId, i);
 304                                 }
 305                             }
 306                         }
 307
 308                         // Update `bookmarksCursor` with the current contents of the bookmarks database.
 309                         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 310
 311                         // Update the `ListView`.
 312                         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 313
 314                         // Scroll with the bookmark.
 315                         scrollBookmarks(selectedBookmarkNewPosition);
 316
 317                         // Update the enabled status of the move icons.
 318                         updateMoveIcons();
 319                         break;
 320
 321                     case R.id.move_bookmark_down:
 322                         // Get the array of checked bookmark positions.
 323                         selectedBookmarksPositionsSparseBooleanArray = bookmarksListView.getCheckedItemPositions();
 324
 325                         // Store the position of the selected bookmark.  Only one bookmark is selected when `move_bookmark_down` is enabled.
 326                         selectedBookmarkPosition = selectedBookmarksPositionsSparseBooleanArray.keyAt(0);
 327
 328                         // Calculate the new position of the selected bookmark.
 329                         selectedBookmarkNewPosition = selectedBookmarkPosition + 1;
 330
 331                         // Iterate through the bookmarks.
 332                         for (int i = 0; i <bookmarksListView.getCount(); i++) {
 333                             // Get the database ID for the current bookmark.
 334                             int currentBookmarkDatabaseId = (int) bookmarksListView.getItemIdAtPosition(i);
 335
 336                             // Update the display order for the current bookmark.
 337                             if (i == selectedBookmarkPosition) {  // The current bookmark is the selected bookmark.
 338                                 // Move the current bookmark down one.
 339                                 bookmarksDatabaseHelper.updateDisplayOrder(currentBookmarkDatabaseId, i + 1);
 340                             } else if ((i - 1) == selectedBookmarkPosition) {  // The current bookmark is immediately below the selected bookmark.
 341                                 // Move the bookmark below the selected bookmark up one.
 342                                 bookmarksDatabaseHelper.updateDisplayOrder(currentBookmarkDatabaseId, i - 1);
 343                             } else {  // The current bookmark is not changing positions.
 344                                 // Move `bookmarksCursor` to the current bookmark position.
 345                                 bookmarksCursor.moveToPosition(i);
 346
 347                                 // Update the display order only if it is not correct in the database.
 348                                 if (bookmarksCursor.getInt(bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper.DISPLAY_ORDER)) != i) {
 349                                     bookmarksDatabaseHelper.updateDisplayOrder(currentBookmarkDatabaseId, i);
 350                                 }
 351                             }
 352                         }
 353
 354                         // Update `bookmarksCursor` with the current contents of the bookmarks database.
 355                         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 356
 357                         // Update the `ListView`.
 358                         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 359
 360                         // Scroll with the bookmark.
 361                         scrollBookmarks(selectedBookmarkNewPosition);
 362
 363                         // Update the enabled status of the move icons.
 364                         updateMoveIcons();
 365                         break;
 366
 367                     case R.id.move_to_folder:
 368                         // Store `checkedItemIds` for use by the `AlertDialog`.
 369                         checkedItemIds = bookmarksListView.getCheckedItemIds();
 370
 371                         // Show the `MoveToFolderDialog` `AlertDialog` and name the instance `@string/move_to_folder
 372                         AppCompatDialogFragment moveToFolderDialog = new MoveToFolderDialog();
 373                         moveToFolderDialog.show(getSupportFragmentManager(), getResources().getString(R.string.move_to_folder));
 374                         break;
 375
 376                     case R.id.edit_bookmark:
 377                         // Get the array of checked bookmark positions.
 378                         selectedBookmarksPositionsSparseBooleanArray = bookmarksListView.getCheckedItemPositions();
 379
 380                         // Get the position of the selected bookmark.  Only one bookmark is selected when `edit_bookmark_down` is enabled.
 381                         selectedBookmarkPosition = selectedBookmarksPositionsSparseBooleanArray.keyAt(0);
 382
 383                         // Move to the selected database ID and find out if it is a folder.
 384                         bookmarksCursor.moveToPosition(selectedBookmarkPosition);
 385                         boolean isFolder = (bookmarksCursor.getInt(bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper.IS_FOLDER)) == 1);
 386
 387                         // Store `checkedItemIds` for use by the `AlertDialog`.
 388                         checkedItemIds = bookmarksListView.getCheckedItemIds();
 389
 390                         if (isFolder) {
 391                             // Save the current folder name, which is used in `onSaveEditBookmarkFolder()`.
 392                             oldFolderNameString = bookmarksCursor.getString(bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_NAME));
 393
 394                             // Show the `EditBookmarkFolderDialog` `AlertDialog` and name the instance `@string/edit_folder`.
 395                             AppCompatDialogFragment editFolderDialog = new EditBookmarkFolderDialog();
 396                             editFolderDialog.show(getSupportFragmentManager(), getResources().getString(R.string.edit_folder));
 397                         } else {
 398                             // Show the `EditBookmarkDialog` `AlertDialog` and name the instance `@string/edit_bookmark`.
 399                             AppCompatDialogFragment editBookmarkDialog = new EditBookmarkDialog();
 400                             editBookmarkDialog.show(getSupportFragmentManager(), getResources().getString(R.string.edit_bookmark));
 401                         }
 402                         break;
 403
 404                     case R.id.delete_bookmark:
 405                         // Get an array of the selected row IDs.
 406                         final long[] selectedBookmarksIdsLongArray = bookmarksListView.getCheckedItemIds();
 407
 408                         // Get the array of checked bookmarks.  `.clone()` makes a copy that won't change if `bookmarksListView` is reloaded, which is needed for re-selecting the bookmarks on undelete.
 409                         selectedBookmarksPositionsSparseBooleanArray = bookmarksListView.getCheckedItemPositions().clone();
 410
 411                         // Update `bookmarksCursor` with the current contents of the bookmarks database except for the specified database IDs.
 412                         bookmarksCursor = bookmarksDatabaseHelper.getBookmarksCursorExcept(selectedBookmarksIdsLongArray, currentFolder);
 413
 414                         // Update the `ListView`.
 415                         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 416
 417                         // Instantiate `snackbarMessage`.
 418                         String snackbarMessage;
 419
 420                         // Determine how many items are in the array and prepare an appropriate `Snackbar` message.
 421                         if (selectedBookmarksIdsLongArray.length == 1) {
 422                             snackbarMessage = getString(R.string.one_bookmark_deleted);
 423                         } else {
 424                             snackbarMessage = selectedBookmarksIdsLongArray.length + " " + getString(R.string.bookmarks_deleted);
 425                         }
 426
 427                         // Show a SnackBar.
 428                         Snackbar.make(findViewById(R.id.bookmarks_coordinatorlayout), snackbarMessage, Snackbar.LENGTH_LONG)
 429                                 .setAction(R.string.undo, new View.OnClickListener() {
 430                                     @Override
 431                                     public void onClick(View view) {
 432                                         // Do nothing because everything will be handled by `onDismissed()` below.
 433                                     }
 434                                 })
 435                                 .addCallback(new Snackbar.Callback() {
 436                                     @Override
 437                                     public void onDismissed(Snackbar snackbar, int event) {
 438                                         switch (event) {
 439                                             // The user pushed the `Undo` button.
 440                                             case Snackbar.Callback.DISMISS_EVENT_ACTION:
 441                                                 // Update `bookmarksCursor` with the current contents of the bookmarks database, including the "deleted" bookmarks.
 442                                                 bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 443
 444                                                 // Update the `ListView`.
 445                                                 bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 446
 447                                                 // Re-select the previously selected bookmarks.
 448                                                 for (int i = 0; i < selectedBookmarksPositionsSparseBooleanArray.size(); i++) {
 449                                                     bookmarksListView.setItemChecked(selectedBookmarksPositionsSparseBooleanArray.keyAt(i), true);
 450                                                 }
 451                                                 break;
 452
 453                                             // The `Snackbar` was dismissed without the `Undo` button being pushed.
 454                                             default:
 455                                                 // Delete each selected bookmark.
 456                                                 for (long databaseIdLong : selectedBookmarksIdsLongArray) {
 457                                                     // Convert `databaseIdLong` to an int.
 458                                                     int databaseIdInt = (int) databaseIdLong;
 459
 460                                                     // Delete the contents of the folder if the selected bookmark is a folder.
 461                                                     if (bookmarksDatabaseHelper.isFolder(databaseIdInt)) {
 462                                                         deleteBookmarkFolderContents(databaseIdInt);
 463                                                     }
 464
 465                                                     // Delete the selected bookmark.
 466                                                     bookmarksDatabaseHelper.deleteBookmark(databaseIdInt);
 467                                                 }
 468
 469                                                 // Update the display order.
 470                                                 for (int i = 0; i < bookmarksListView.getCount(); i++) {
 471                                                     // Get the database ID for the current bookmark.
 472                                                     int currentBookmarkDatabaseId = (int) bookmarksListView.getItemIdAtPosition(i);
 473
 474                                                     // Move `bookmarksCursor` to the current bookmark position.
 475                                                     bookmarksCursor.moveToPosition(i);
 476
 477                                                     // Update the display order only if it is not correct in the database.
 478                                                     if (bookmarksCursor.getInt(bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper.DISPLAY_ORDER)) != i) {
 479                                                         bookmarksDatabaseHelper.updateDisplayOrder(currentBookmarkDatabaseId, i);
 480                                                     }
 481                                                 }
 482                                                 break;
 483                                         }
 484                                     }
 485                                 })
 486                                 //Show the `SnackBar`.
 487                                 .show();
 488
 489                         // Close the `ActionBar`.
 490                         mode.finish();
 491                         break;
 492
 493                     case R.id.context_menu_select_all_bookmarks:
 494                         // Get the total number of bookmarks.
 495                         int numberOfBookmarks = bookmarksListView.getCount();
 496
 497                         // Select them all.
 498                         for (int i = 0; i < numberOfBookmarks; i++) {
 499                             bookmarksListView.setItemChecked(i, true);
 500                         }
 501                         break;
 502                 }
 503
 504                 // Consume the click.
 505                 return true;
 506             }
 507
 508             @Override
 509             public void onDestroyActionMode(ActionMode mode) {
 510                 // Do nothing.
 511             }
 512         });
 513
 514         // Get handles for the `FloatingActionButtons`.
 515         FloatingActionButton createBookmarkFolderFab = (FloatingActionButton) findViewById(R.id.create_bookmark_folder_fab);
 516         FloatingActionButton createBookmarkFab = (FloatingActionButton) findViewById(R.id.create_bookmark_fab);
 517
 518         // Set the create new bookmark folder FAB to display the `AlertDialog`.
 519         createBookmarkFolderFab.setOnClickListener(new View.OnClickListener() {
 520             @Override
 521             public void onClick(View v) {
 522                 // Show the `CreateBookmarkFolderDialog` `AlertDialog` and name the instance `@string/create_folder`.
 523                 AppCompatDialogFragment createBookmarkFolderDialog = new CreateBookmarkFolderDialog();
 524                 createBookmarkFolderDialog.show(getSupportFragmentManager(), getResources().getString(R.string.create_folder));
 525             }
 526         });
 527
 528         // Set the create new bookmark FAB to display the `AlertDialog`.
 529         createBookmarkFab.setOnClickListener(new View.OnClickListener() {
 530             @Override
 531             public void onClick(View view) {
 532                 // Show the `CreateBookmarkDialog` `AlertDialog` and name the instance `@string/create_bookmark`.
 533                 AppCompatDialogFragment createBookmarkDialog = new CreateBookmarkDialog();
 534                 createBookmarkDialog.show(getSupportFragmentManager(), getResources().getString(R.string.create_bookmark));
 535             }
 536         });
 537     }
 538
 539     @Override
 540     public boolean onCreateOptionsMenu(Menu menu) {
 541         // Inflate the menu.
 542         getMenuInflater().inflate(R.menu.bookmarks_options_menu, menu);
 543
 544         // Success.
 545         return true;
 546     }
 547
 548     @Override
 549     public boolean onOptionsItemSelected(MenuItem menuItem) {
 550         // Get the ID of the `MenuItem` that was selected.
 551         int menuItemId = menuItem.getItemId();
 552
 553         switch (menuItemId) {
 554             case android.R.id.home:  // The home arrow is identified as `android.R.id.home`, not just `R.id.home`.
 555                 if (currentFolder.isEmpty()) {  // Currently in the home folder.
 556                     // Return to `MainWebViewActivity`.
 557                     NavUtils.navigateUpFromSameTask(this);
 558                 } else {  // Currently in a subfolder.
 559                     // Place the former parent folder in `currentFolder`.
 560                     currentFolder = bookmarksDatabaseHelper.getParentFolder(currentFolder);
 561
 562                     // Load the new folder.
 563                     loadFolder();
 564                 }
 565                 break;
 566
 567             case R.id.options_menu_select_all_bookmarks:
 568                 // Get the total number of bookmarks.
 569                 int numberOfBookmarks = bookmarksListView.getCount();
 570
 571                 // Select them all.
 572                 for (int i = 0; i < numberOfBookmarks; i++) {
 573                     bookmarksListView.setItemChecked(i, true);
 574                 }
 575                 break;
 576
 577             case R.id.bookmarks_database_view:
 578                 // Launch `BookmarksDatabaseViewActivity`.
 579                 Intent bookmarksDatabaseViewIntent = new Intent(this, BookmarksDatabaseViewActivity.class);
 580                 startActivity(bookmarksDatabaseViewIntent);
 581                 break;
 582         }
 583         return true;
 584     }
 585
 586     @Override
 587     public void onBackPressed() {
 588         if (currentFolder.isEmpty()) {  // Currently in the home folder.
 589             // Exit `BookmarksActivity`.
 590             super.onBackPressed();
 591         } else {  // Currently in a subfolder.
 592             // Place the former parent folder in `currentFolder`.
 593             currentFolder = bookmarksDatabaseHelper.getParentFolder(currentFolder);
 594
 595             // Load the new folder.
 596             loadFolder();
 597         }
 598     }
 599
 600     @Override
 601     public void onCreateBookmark(AppCompatDialogFragment dialogFragment) {
 602         // Get the `EditTexts` from the `dialogFragment`.
 603         EditText createBookmarkNameEditText = (EditText) dialogFragment.getDialog().findViewById(R.id.create_bookmark_name_edittext);
 604         EditText createBookmarkUrlEditText = (EditText) dialogFragment.getDialog().findViewById(R.id.create_bookmark_url_edittext);
 605
 606         // Extract the strings from the `EditTexts`.
 607         String bookmarkNameString = createBookmarkNameEditText.getText().toString();
 608         String bookmarkUrlString = createBookmarkUrlEditText.getText().toString();
 609
 610         // Convert the favoriteIcon Bitmap to a byte array.
 611         ByteArrayOutputStream favoriteIconByteArrayOutputStream = new ByteArrayOutputStream();
 612         // `0` is for lossless compression (the only option for a PNG).
 613         MainWebViewActivity.favoriteIconBitmap.compress(Bitmap.CompressFormat.PNG, 0, favoriteIconByteArrayOutputStream);
 614         byte[] favoriteIconByteArray = favoriteIconByteArrayOutputStream.toByteArray();
 615
 616         // Display the new bookmark below the current items in the (0 indexed) list.
 617         int newBookmarkDisplayOrder = bookmarksListView.getCount();
 618
 619         // Create the bookmark.
 620         bookmarksDatabaseHelper.createBookmark(bookmarkNameString, bookmarkUrlString, newBookmarkDisplayOrder, currentFolder, favoriteIconByteArray);
 621
 622         // Update `bookmarksCursor` with the current contents of this folder.
 623         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 624
 625         // Update the `ListView`.
 626         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 627
 628         // Scroll to the new bookmark.
 629         bookmarksListView.setSelection(newBookmarkDisplayOrder);
 630     }
 631
 632     @Override
 633     public void onCreateBookmarkFolder(AppCompatDialogFragment dialogFragment) {
 634         // Get handles for the views in `dialogFragment`.
 635         EditText createFolderNameEditText = (EditText) dialogFragment.getDialog().findViewById(R.id.create_folder_name_edittext);
 636         RadioButton defaultFolderIconRadioButton = (RadioButton) dialogFragment.getDialog().findViewById(R.id.create_folder_default_icon_radiobutton);
 637         ImageView folderIconImageView = (ImageView) dialogFragment.getDialog().findViewById(R.id.create_folder_default_icon);
 638
 639         // Get new folder name string.
 640         String folderNameString = createFolderNameEditText.getText().toString();
 641
 642         // Get the new folder icon `Bitmap`.
 643         Bitmap folderIconBitmap;
 644         if (defaultFolderIconRadioButton.isChecked()) {  // Use the default folder icon.
 645             // Get the default folder icon and convert it to a `Bitmap`.
 646             Drawable folderIconDrawable = folderIconImageView.getDrawable();
 647             BitmapDrawable folderIconBitmapDrawable = (BitmapDrawable) folderIconDrawable;
 648             folderIconBitmap = folderIconBitmapDrawable.getBitmap();
 649         } else {  // Use the `WebView` favorite icon.
 650             folderIconBitmap = MainWebViewActivity.favoriteIconBitmap;
 651         }
 652
 653         // Convert `folderIconBitmap` to a byte array.  `0` is for lossless compression (the only option for a PNG).
 654         ByteArrayOutputStream folderIconByteArrayOutputStream = new ByteArrayOutputStream();
 655         folderIconBitmap.compress(Bitmap.CompressFormat.PNG, 0, folderIconByteArrayOutputStream);
 656         byte[] folderIconByteArray = folderIconByteArrayOutputStream.toByteArray();
 657
 658         // Move all the bookmarks down one in the display order.
 659         for (int i = 0; i < bookmarksListView.getCount(); i++) {
 660             int databaseId = (int) bookmarksListView.getItemIdAtPosition(i);
 661             bookmarksDatabaseHelper.updateDisplayOrder(databaseId, i + 1);
 662         }
 663
 664         // Create the folder, placing it at the top of the ListView
 665         bookmarksDatabaseHelper.createFolder(folderNameString, 0, currentFolder, folderIconByteArray);
 666
 667         // Update `bookmarksCursor` with the current contents of this folder.
 668         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 669
 670         // Update the `ListView`.
 671         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 672
 673         // Scroll to the new folder.
 674         bookmarksListView.setSelection(0);
 675     }
 676
 677     @Override
 678     public void onSaveEditBookmark(AppCompatDialogFragment dialogFragment) {
 679         // Get handles for the views from `dialogFragment`.
 680         EditText editBookmarkNameEditText = (EditText) dialogFragment.getDialog().findViewById(R.id.edit_bookmark_name_edittext);
 681         EditText editBookmarkUrlEditText = (EditText) dialogFragment.getDialog().findViewById(R.id.edit_bookmark_url_edittext);
 682         RadioButton currentBookmarkIconRadioButton = (RadioButton) dialogFragment.getDialog().findViewById(R.id.edit_bookmark_current_icon_radiobutton);
 683
 684         // Store the bookmark strings.
 685         String bookmarkNameString = editBookmarkNameEditText.getText().toString();
 686         String bookmarkUrlString = editBookmarkUrlEditText.getText().toString();
 687
 688         // Get an array of the selected row IDs.
 689         long[] selectedBookmarksLongArray = bookmarksListView.getCheckedItemIds();
 690
 691         // Get the database ID of the selected bookmark.  Editing a bookmark is only possible where only one item is selected.
 692         int selectedBookmarkDatabaseId = (int) selectedBookmarksLongArray[0];
 693
 694         // Update the bookmark.
 695         if (currentBookmarkIconRadioButton.isChecked()) {  // Update the bookmark without changing the favorite icon.
 696             bookmarksDatabaseHelper.updateBookmark(selectedBookmarkDatabaseId, bookmarkNameString, bookmarkUrlString);
 697         } else {  // Update the bookmark using the `WebView` favorite icon.
 698             // Convert the favorite icon to a byte array.  `0` is for lossless compression (the only option for a PNG).
 699             ByteArrayOutputStream newFavoriteIconByteArrayOutputStream = new ByteArrayOutputStream();
 700             MainWebViewActivity.favoriteIconBitmap.compress(Bitmap.CompressFormat.PNG, 0, newFavoriteIconByteArrayOutputStream);
 701             byte[] newFavoriteIconByteArray = newFavoriteIconByteArrayOutputStream.toByteArray();
 702
 703             //  Update the bookmark and the favorite icon.
 704             bookmarksDatabaseHelper.updateBookmark(selectedBookmarkDatabaseId, bookmarkNameString, bookmarkUrlString, newFavoriteIconByteArray);
 705         }
 706
 707         // Close the contextual action mode.
 708         contextualActionMode.finish();
 709
 710         // Update `bookmarksCursor` with the current contents of this folder.
 711         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 712
 713         // Update the `ListView`.
 714         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 715     }
 716
 717     @Override
 718     public void onSaveEditBookmarkFolder(AppCompatDialogFragment dialogFragment) {
 719         // Get handles for the views from `dialogFragment`.
 720         EditText editFolderNameEditText = (EditText) dialogFragment.getDialog().findViewById(R.id.edit_folder_name_edittext);
 721         RadioButton currentFolderIconRadioButton = (RadioButton) dialogFragment.getDialog().findViewById(R.id.edit_folder_current_icon_radiobutton);
 722         RadioButton defaultFolderIconRadioButton = (RadioButton) dialogFragment.getDialog().findViewById(R.id.edit_folder_default_icon_radiobutton);
 723         ImageView folderIconImageView = (ImageView) dialogFragment.getDialog().findViewById(R.id.edit_folder_default_icon);
 724
 725         // Get the new folder name.
 726         String newFolderNameString = editFolderNameEditText.getText().toString();
 727
 728         // Get an array of the selected row IDs.
 729         long[] selectedBookmarksLongArray = bookmarksListView.getCheckedItemIds();
 730
 731         // Get the database ID of the selected bookmark.  Editing a folder is only possible where only one item is selected.
 732         int selectedFolderDatabaseId = (int) selectedBookmarksLongArray[0];
 733
 734         // Check if the favorite icon has changed.
 735         if (currentFolderIconRadioButton.isChecked()) {  // Only the name has changed.
 736             // Update the name in the database.
 737             bookmarksDatabaseHelper.updateFolder(selectedFolderDatabaseId, oldFolderNameString, newFolderNameString);
 738         } else if (!currentFolderIconRadioButton.isChecked() && newFolderNameString.equals(oldFolderNameString)) {  // Only the icon has changed.
 739             // Get the new folder icon `Bitmap`.
 740             Bitmap folderIconBitmap;
 741             if (defaultFolderIconRadioButton.isChecked()) {
 742                 // Get the default folder icon and convert it to a `Bitmap`.
 743                 Drawable folderIconDrawable = folderIconImageView.getDrawable();
 744                 BitmapDrawable folderIconBitmapDrawable = (BitmapDrawable) folderIconDrawable;
 745                 folderIconBitmap = folderIconBitmapDrawable.getBitmap();
 746             } else {  // Use the `WebView` favorite icon.
 747                 folderIconBitmap = MainWebViewActivity.favoriteIconBitmap;
 748             }
 749
 750             // Convert the folder `Bitmap` to a byte array.  `0` is for lossless compression (the only option for a PNG).
 751             ByteArrayOutputStream folderIconByteArrayOutputStream = new ByteArrayOutputStream();
 752             folderIconBitmap.compress(Bitmap.CompressFormat.PNG, 0, folderIconByteArrayOutputStream);
 753             byte[] folderIconByteArray = folderIconByteArrayOutputStream.toByteArray();
 754
 755             // Update the folder icon in the database.
 756             bookmarksDatabaseHelper.updateFolder(selectedFolderDatabaseId, folderIconByteArray);
 757         } else {  // The folder icon and the name have changed.
 758             // Get the new folder icon `Bitmap`.
 759             Bitmap folderIconBitmap;
 760             if (defaultFolderIconRadioButton.isChecked()) {
 761                 // Get the default folder icon and convert it to a `Bitmap`.
 762                 Drawable folderIconDrawable = folderIconImageView.getDrawable();
 763                 BitmapDrawable folderIconBitmapDrawable = (BitmapDrawable) folderIconDrawable;
 764                 folderIconBitmap = folderIconBitmapDrawable.getBitmap();
 765             } else {  // Use the `WebView` favorite icon.
 766                 folderIconBitmap = MainWebViewActivity.favoriteIconBitmap;
 767             }
 768
 769             // Convert the folder `Bitmap` to a byte array.  `0` is for lossless compression (the only option for a PNG).
 770             ByteArrayOutputStream folderIconByteArrayOutputStream = new ByteArrayOutputStream();
 771             folderIconBitmap.compress(Bitmap.CompressFormat.PNG, 0, folderIconByteArrayOutputStream);
 772             byte[] folderIconByteArray = folderIconByteArrayOutputStream.toByteArray();
 773
 774             // Update the folder name and icon in the database.
 775             bookmarksDatabaseHelper.updateFolder(selectedFolderDatabaseId, oldFolderNameString, newFolderNameString, folderIconByteArray);
 776         }
 777
 778         // Update `bookmarksCursor` with the current contents of this folder.
 779         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 780
 781         // Update the `ListView`.
 782         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 783
 784         // Close the contextual action mode.
 785         contextualActionMode.finish();
 786     }
 787
 788     @Override
 789     public void onMoveToFolder(AppCompatDialogFragment dialogFragment) {
 790         // Get a handle for the `ListView` from `dialogFragment`.
 791         ListView folderListView = (ListView) dialogFragment.getDialog().findViewById(R.id.move_to_folder_listview);
 792
 793         // Store a long array of the selected folders.
 794         long[] newFolderLongArray = folderListView.getCheckedItemIds();
 795
 796         // Get the new folder database ID.  Only one folder will be selected.
 797         int newFolderDatabaseId = (int) newFolderLongArray[0];
 798
 799         // Instantiate `newFolderName`.
 800         String newFolderName;
 801
 802         // Set the new folder name.
 803         if (newFolderDatabaseId == 0) {
 804             // The new folder is the home folder, represented as `""` in the database.
 805             newFolderName = "";
 806         } else {
 807             // Get the new folder name from the database.
 808             newFolderName = bookmarksDatabaseHelper.getFolderName(newFolderDatabaseId);
 809         }
 810
 811         // Get a long array with the the database ID of the selected bookmarks.
 812         long[] selectedBookmarksLongArray = bookmarksListView.getCheckedItemIds();
 813
 814         // Move each of the selected bookmarks to the new folder.
 815         for (long databaseIdLong : selectedBookmarksLongArray) {
 816             // Get `databaseIdInt` for each selected bookmark.
 817             int databaseIdInt = (int) databaseIdLong;
 818
 819             // Move the selected bookmark to the new folder.
 820             bookmarksDatabaseHelper.moveToFolder(databaseIdInt, newFolderName);
 821         }
 822
 823         // Update `bookmarksCursor` with the current contents of this folder.
 824         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 825
 826         // Update the `ListView`.
 827         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 828
 829         // Close the contextual app bar.
 830         contextualActionMode.finish();
 831     }
 832
 833     private void deleteBookmarkFolderContents(int databaseId) {
 834         // Get the name of the folder.
 835         String folderName = bookmarksDatabaseHelper.getFolderName(databaseId);
 836
 837         // Get the contents of the folder.
 838         Cursor folderCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(folderName);
 839
 840         // Delete each of the bookmarks in the folder.
 841         for (int i = 0; i < folderCursor.getCount(); i++) {
 842             // Move `folderCursor` to the current row.
 843             folderCursor.moveToPosition(i);
 844
 845             // Get the database ID of the item.
 846             int itemDatabaseId = folderCursor.getInt(folderCursor.getColumnIndex(BookmarksDatabaseHelper._ID));
 847
 848             // If this is a folder, recursively delete the contents first.
 849             if (bookmarksDatabaseHelper.isFolder(itemDatabaseId)) {
 850                 deleteBookmarkFolderContents(itemDatabaseId);
 851             }
 852
 853             // Delete the bookmark.
 854             bookmarksDatabaseHelper.deleteBookmark(itemDatabaseId);
 855         }
 856     }
 857
 858     private void updateMoveIcons() {
 859         // Get a long array of the selected bookmarks.
 860         long[] selectedBookmarksLongArray = bookmarksListView.getCheckedItemIds();
 861
 862         // Get the database IDs for the first, last, and selected bookmarks.
 863         int selectedBookmarkDatabaseId = (int) selectedBookmarksLongArray[0];
 864         int firstBookmarkDatabaseId = (int) bookmarksListView.getItemIdAtPosition(0);
 865         // bookmarksListView is 0 indexed.
 866         int lastBookmarkDatabaseId = (int) bookmarksListView.getItemIdAtPosition(bookmarksListView.getCount() - 1);
 867
 868         // Update the move bookmark up `MenuItem`.
 869         if (selectedBookmarkDatabaseId == firstBookmarkDatabaseId) {  // The selected bookmark is in the first position.
 870             // Disable the move bookmark up `MenuItem`.
 871             moveBookmarkUpMenuItem.setEnabled(false);
 872
 873             //  Set the move bookmark up icon to be ghosted.
 874             moveBookmarkUpMenuItem.setIcon(R.drawable.move_up_disabled);
 875         } else {  // The selected bookmark is not in the first position.
 876             // Enable the move bookmark up `MenuItem`.
 877             moveBookmarkUpMenuItem.setEnabled(true);
 878
 879             // Set the icon according to the theme.
 880             if (MainWebViewActivity.darkTheme) {
 881                 moveBookmarkUpMenuItem.setIcon(R.drawable.move_up_enabled_dark);
 882             } else {
 883                 moveBookmarkUpMenuItem.setIcon(R.drawable.move_up_enabled_light);
 884             }
 885         }
 886
 887         // Update the move bookmark down `MenuItem`.
 888         if (selectedBookmarkDatabaseId == lastBookmarkDatabaseId) {  // The selected bookmark is in the last position.
 889             // Disable the move bookmark down `MenuItem`.
 890             moveBookmarkDownMenuItem.setEnabled(false);
 891
 892             // Set the move bookmark down icon to be ghosted.
 893             moveBookmarkDownMenuItem.setIcon(R.drawable.move_down_disabled);
 894         } else {  // The selected bookmark is not in the last position.
 895             // Enable the move bookmark down `MenuItem`.
 896             moveBookmarkDownMenuItem.setEnabled(true);
 897
 898             // Set the icon according to the theme.
 899             if (MainWebViewActivity.darkTheme) {
 900                 moveBookmarkDownMenuItem.setIcon(R.drawable.move_down_enabled_dark);
 901             } else {
 902                 moveBookmarkDownMenuItem.setIcon(R.drawable.move_down_enabled_light);
 903             }
 904         }
 905     }
 906
 907     private void scrollBookmarks(int selectedBookmarkPosition) {
 908         // Get the first and last visible bookmark positions.
 909         int firstVisibleBookmarkPosition = bookmarksListView.getFirstVisiblePosition();
 910         int lastVisibleBookmarkPosition = bookmarksListView.getLastVisiblePosition();
 911
 912         // Calculate the number of bookmarks per screen.
 913         int numberOfBookmarksPerScreen = lastVisibleBookmarkPosition - firstVisibleBookmarkPosition;
 914
 915         // Scroll with the moved bookmark if necessary.
 916         if (selectedBookmarkPosition <= firstVisibleBookmarkPosition) {  // The selected bookmark position is at or above the top of the screen.
 917             // Scroll to the selected bookmark position.
 918             bookmarksListView.setSelection(selectedBookmarkPosition);
 919         } else if (selectedBookmarkPosition >= (lastVisibleBookmarkPosition - 1)) {  // The selected bookmark is at or below the bottom of the screen.  The `-1` handles partial bookmarks displayed at the bottom of the `ListView`.
 920             // Scroll to display the selected bookmark at the bottom of the screen.  `+1` assured that the entire bookmark will be displayed in situations where only a partial bookmark fits at the bottom of the `ListView`.
 921             bookmarksListView.setSelection(selectedBookmarkPosition - numberOfBookmarksPerScreen + 1);
 922         }
 923     }
 924
 925     private void loadFolder() {
 926         // Update `bookmarksCursor` with the contents of the bookmarks database for the current folder.
 927         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksCursorByDisplayOrder(currentFolder);
 928
 929         // Setup a `CursorAdapter`.  `this` specifies the `Context`.  `false` disables `autoRequery`.
 930         bookmarksCursorAdapter = new CursorAdapter(this, bookmarksCursor, false) {
 931             @Override
 932             public View newView(Context context, Cursor cursor, ViewGroup parent) {
 933                 // Inflate the individual item layout.  `false` does not attach it to the root.
 934                 return getLayoutInflater().inflate(R.layout.bookmarks_item_linearlayout, parent, false);
 935             }
 936
 937             @Override
 938             public void bindView(View view, Context context, Cursor cursor) {
 939                 // Get handles for the views.
 940                 ImageView bookmarkFavoriteIcon = (ImageView) view.findViewById(R.id.bookmark_favorite_icon);
 941                 TextView bookmarkNameTextView = (TextView) view.findViewById(R.id.bookmark_name);
 942
 943                 // Get the favorite icon byte array from the `Cursor`.
 944                 byte[] favoriteIconByteArray = cursor.getBlob(cursor.getColumnIndex(BookmarksDatabaseHelper.FAVORITE_ICON));
 945
 946                 // Convert the byte array to a `Bitmap` beginning at the first byte and ending at the last.
 947                 Bitmap favoriteIconBitmap = BitmapFactory.decodeByteArray(favoriteIconByteArray, 0, favoriteIconByteArray.length);
 948
 949                 // Display the bitmap in `bookmarkFavoriteIcon`.
 950                 bookmarkFavoriteIcon.setImageBitmap(favoriteIconBitmap);
 951
 952                 // Get the bookmark name from the cursor and display it in `bookmarkNameTextView`.
 953                 String bookmarkNameString = cursor.getString(cursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_NAME));
 954                 bookmarkNameTextView.setText(bookmarkNameString);
 955
 956                 // Make the font bold for folders.
 957                 if (cursor.getInt(cursor.getColumnIndex(BookmarksDatabaseHelper.IS_FOLDER)) == 1) {
 958                     bookmarkNameTextView.setTypeface(Typeface.DEFAULT_BOLD);
 959                 } else {  // Reset the font to default for normal bookmarks.
 960                     bookmarkNameTextView.setTypeface(Typeface.DEFAULT);
 961                 }
 962             }
 963         };
 964
 965         // Populate the `ListView` with the adapter.
 966         bookmarksListView.setAdapter(bookmarksCursorAdapter);
 967
 968         // Set the `AppBar` title.
 969         if (currentFolder.isEmpty()) {
 970             appBar.setTitle(R.string.bookmarks);
 971         } else {
 972             appBar.setTitle(currentFolder);
 973         }
 974     }
 975 }