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

   1 /*
   2  * Copyright © 2016-2020 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.annotation.SuppressLint;
  23 import android.app.Dialog;
  24 import android.content.Context;
  25 import android.content.Intent;
  26 import android.content.SharedPreferences;
  27 import android.database.Cursor;
  28 import android.database.MatrixCursor;
  29 import android.database.MergeCursor;
  30 import android.graphics.Bitmap;
  31 import android.graphics.BitmapFactory;
  32 import android.graphics.Typeface;
  33 import android.graphics.drawable.BitmapDrawable;
  34 import android.graphics.drawable.Drawable;
  35 import android.os.Bundle;
  36 import android.preference.PreferenceManager;
  37 import android.util.SparseBooleanArray;
  38 import android.view.ActionMode;
  39 import android.view.Menu;
  40 import android.view.MenuItem;
  41 import android.view.View;
  42 import android.view.ViewGroup;
  43 import android.view.WindowManager;
  44 import android.widget.AbsListView;
  45 import android.widget.AdapterView;
  46 import android.widget.EditText;
  47 import android.widget.ImageView;
  48 import android.widget.ListView;
  49 import android.widget.RadioButton;
  50 import android.widget.ResourceCursorAdapter;
  51 import android.widget.Spinner;
  52 import android.widget.TextView;
  53
  54 import androidx.appcompat.app.ActionBar;
  55 import androidx.appcompat.app.AppCompatActivity;
  56 import androidx.appcompat.widget.Toolbar;  // The AndroidX toolbar must be used until the minimum API is >= 21.
  57 import androidx.core.content.ContextCompat;
  58 import androidx.cursoradapter.widget.CursorAdapter;
  59 import androidx.fragment.app.DialogFragment;  // The AndroidX dialog fragment must be used or an error is produced on API <=22.
  60
  61 import com.google.android.material.snackbar.Snackbar;
  62
  63 import com.stoutner.privacybrowser.R;
  64 import com.stoutner.privacybrowser.dialogs.EditBookmarkDatabaseViewDialog;
  65 import com.stoutner.privacybrowser.dialogs.EditBookmarkFolderDatabaseViewDialog;
  66 import com.stoutner.privacybrowser.helpers.BookmarksDatabaseHelper;
  67
  68 import java.io.ByteArrayOutputStream;
  69 import java.util.Arrays;
  70
  71 public class BookmarksDatabaseViewActivity extends AppCompatActivity implements EditBookmarkDatabaseViewDialog.EditBookmarkDatabaseViewListener,
  72         EditBookmarkFolderDatabaseViewDialog.EditBookmarkFolderDatabaseViewListener {
  73     // Instantiate the constants.
  74     private static final int ALL_FOLDERS_DATABASE_ID = -2;
  75     private static final int HOME_FOLDER_DATABASE_ID = -1;
  76
  77     // `bookmarksDatabaseHelper` is used in `onCreate()`, `updateBookmarksListView()`, `selectAllBookmarksInFolder()`, and `onDestroy()`.
  78     private BookmarksDatabaseHelper bookmarksDatabaseHelper;
  79
  80     // `bookmarksCursor` is used in `onCreate()`, `updateBookmarksListView()`, `onSaveBookmark()`, `onSaveBookmarkFolder()`, and `onDestroy()`.
  81     private Cursor bookmarksCursor;
  82
  83     // `bookmarksCursorAdapter` is used in `onCreate()`, `selectAllBookmarksInFolder()`, and `updateBookmarksListView()`.
  84     private CursorAdapter bookmarksCursorAdapter;
  85
  86     // `oldFolderNameString` is used in `onCreate()` and `onSaveBookmarkFolder()`.
  87     private String oldFolderNameString;
  88
  89     // `currentFolderDatabaseId` is used in `onCreate()`, `updateBookmarksListView()`, `onSaveBookmark()`, and `onSaveBookmarkFolder()`.
  90     private int currentFolderDatabaseId;
  91
  92     // `currentFolder` is used in `onCreate()`, `onSaveBookmark()`, and `onSaveBookmarkFolder()`.
  93     private String currentFolderName;
  94
  95     // `sortByDisplayOrder` is used in `onCreate()`, `onOptionsItemSelected()`, and `updateBookmarksListView()`.
  96     private boolean sortByDisplayOrder;
  97
  98     // `bookmarksDeletedSnackbar` is used in `onCreate()`, `onOptionsItemSelected()`, and `onBackPressed()`.
  99     private Snackbar bookmarksDeletedSnackbar;
 100
 101     // `closeActivityAfterDismissingSnackbar` is used in `onCreate()`, `onOptionsItemSelected()`, and `onBackPressed()`.
 102     private boolean closeActivityAfterDismissingSnackbar;
 103
 104     @Override
 105     public void onCreate(Bundle savedInstanceState) {
 106         // Get a handle for the shared preferences.
 107         SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
 108
 109         // Get the theme and screenshot preferences.
 110         boolean darkTheme = sharedPreferences.getBoolean("dark_theme", false);
 111         boolean allowScreenshots = sharedPreferences.getBoolean("allow_screenshots", false);
 112
 113         // Disable screenshots if not allowed.
 114         if (!allowScreenshots) {
 115             getWindow().addFlags(WindowManager.LayoutParams.FLAG_SECURE);
 116         }
 117
 118         // Set the activity theme.
 119         if (darkTheme) {
 120             setTheme(R.style.PrivacyBrowserDark_SecondaryActivity);
 121         } else {
 122             setTheme(R.style.PrivacyBrowserLight_SecondaryActivity);
 123         }
 124
 125         // Run the default commands.
 126         super.onCreate(savedInstanceState);
 127
 128         // Get the intent that launched the activity.
 129         Intent launchingIntent = getIntent();
 130
 131         // Get the favorite icon byte array.
 132         byte[] favoriteIconByteArray = launchingIntent.getByteArrayExtra("favorite_icon_byte_array");
 133
 134         // Remove the incorrect lint warning below that the favorite icon byte array might be null.
 135         assert favoriteIconByteArray != null;
 136
 137         // Convert the favorite icon byte array to a bitmap and store it in a class variable.
 138         Bitmap favoriteIconBitmap = BitmapFactory.decodeByteArray(favoriteIconByteArray, 0, favoriteIconByteArray.length);
 139
 140         // Set the content view.
 141         setContentView(R.layout.bookmarks_databaseview_coordinatorlayout);
 142
 143         // The AndroidX toolbar must be used until the minimum API is >= 21.
 144         Toolbar toolbar = findViewById(R.id.bookmarks_databaseview_toolbar);
 145         setSupportActionBar(toolbar);
 146
 147         // Get a handle for the action bar.
 148         ActionBar actionBar = getSupportActionBar();
 149
 150         // Remove the incorrect lint warning that the action bar might be null.
 151         assert actionBar != null;
 152
 153         // Display the spinner and the back arrow in the action bar.
 154         actionBar.setCustomView(R.layout.spinner);
 155         actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM | ActionBar.DISPLAY_HOME_AS_UP);
 156
 157         // Initialize the database handler.  The `0` is to specify a database version, but that is set instead using a constant in `BookmarksDatabaseHelper`.
 158         bookmarksDatabaseHelper = new BookmarksDatabaseHelper(this, null, null, 0);
 159
 160         // Setup a matrix cursor for "All Folders" and "Home Folder".
 161         String[] matrixCursorColumnNames = {BookmarksDatabaseHelper._ID, BookmarksDatabaseHelper.BOOKMARK_NAME};
 162         MatrixCursor matrixCursor = new MatrixCursor(matrixCursorColumnNames);
 163         matrixCursor.addRow(new Object[]{ALL_FOLDERS_DATABASE_ID, getString(R.string.all_folders)});
 164         matrixCursor.addRow(new Object[]{HOME_FOLDER_DATABASE_ID, getString(R.string.home_folder)});
 165
 166         // Get a cursor with the list of all the folders.
 167         Cursor foldersCursor = bookmarksDatabaseHelper.getAllFolders();
 168
 169         // Combine `matrixCursor` and `foldersCursor`.
 170         MergeCursor foldersMergeCursor = new MergeCursor(new Cursor[]{matrixCursor, foldersCursor});
 171
 172
 173         // Get the default folder bitmap.  `ContextCompat` must be used until the minimum API >= 21.
 174         Drawable defaultFolderDrawable = ContextCompat.getDrawable(getApplicationContext(), R.drawable.folder_blue_bitmap);
 175
 176         // Cast the default folder drawable to a `BitmapDrawable`.
 177         BitmapDrawable defaultFolderBitmapDrawable = (BitmapDrawable) defaultFolderDrawable;
 178
 179         // Remove the incorrect lint warning that `.getBitmap()` might be null.
 180         assert defaultFolderBitmapDrawable != null;
 181
 182         // Convert the default folder `BitmapDrawable` to a bitmap.
 183         Bitmap defaultFolderBitmap = defaultFolderBitmapDrawable.getBitmap();
 184
 185
 186         // Create a resource cursor adapter for the spinner.
 187         ResourceCursorAdapter foldersCursorAdapter = new ResourceCursorAdapter(this, R.layout.appbar_spinner_item, foldersMergeCursor, 0) {
 188             @Override
 189             public void bindView(View view, Context context, Cursor cursor) {
 190                 // Get handles for the spinner views.
 191                 ImageView spinnerItemImageView = view.findViewById(R.id.spinner_item_imageview);
 192                 TextView spinnerItemTextView = view.findViewById(R.id.spinner_item_textview);
 193
 194                 // Set the folder icon according to the type.
 195                 if (foldersMergeCursor.getPosition() > 1) {  // Set a user folder icon.
 196                     // Initialize a default folder icon byte array output stream.
 197                     ByteArrayOutputStream defaultFolderIconByteArrayOutputStream = new ByteArrayOutputStream();
 198
 199                     // Covert the default folder bitmap to a PNG and store it in the output stream.  `0` is for lossless compression (the only option for a PNG).
 200                     defaultFolderBitmap.compress(Bitmap.CompressFormat.PNG, 0, defaultFolderIconByteArrayOutputStream);
 201
 202                     // Convert the default folder icon output stream to a byte array.
 203                     byte[] defaultFolderIconByteArray = defaultFolderIconByteArrayOutputStream.toByteArray();
 204
 205
 206                     // Get the folder icon byte array from the cursor.
 207                     byte[] folderIconByteArray = cursor.getBlob(cursor.getColumnIndex(BookmarksDatabaseHelper.FAVORITE_ICON));
 208
 209                     // Convert the byte array to a bitmap beginning at the first byte and ending at the last.
 210                     Bitmap folderIconBitmap = BitmapFactory.decodeByteArray(folderIconByteArray, 0, folderIconByteArray.length);
 211
 212
 213                     // Set the icon according to the type.
 214                     if (Arrays.equals(folderIconByteArray, defaultFolderIconByteArray)) {  // The default folder icon is used.
 215                         // Set a smaller and darker folder icon, which works well with the spinner.
 216                         spinnerItemImageView.setImageDrawable(ContextCompat.getDrawable(context, R.drawable.folder_dark_blue));
 217                     } else {  // A custom folder icon is uses.
 218                         // Set the folder image stored in the cursor.
 219                         spinnerItemImageView.setImageBitmap(folderIconBitmap);
 220                     }
 221                 } else {  // Set the `All Folders` or `Home Folder` icon.
 222                     // Set the gray folder image.  `ContextCompat` must be used until the minimum API >= 21.
 223                     spinnerItemImageView.setImageDrawable(ContextCompat.getDrawable(context, R.drawable.folder_gray));
 224                 }
 225
 226                 // Set the text view to display the folder name.
 227                 spinnerItemTextView.setText(cursor.getString(cursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_NAME)));
 228             }
 229         };
 230
 231         // Set the resource cursor adapter drop drown view resource.
 232         foldersCursorAdapter.setDropDownViewResource(R.layout.appbar_spinner_dropdown_item);
 233
 234         // Get a handle for the folder spinner and set the adapter.
 235         Spinner folderSpinner = findViewById(R.id.spinner);
 236         folderSpinner.setAdapter(foldersCursorAdapter);
 237
 238         // Handle taps on the spinner dropdown.
 239         folderSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
 240             @Override
 241             public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
 242                 // Store the current folder database ID.
 243                 currentFolderDatabaseId = (int) id;
 244
 245                 // Get a handle for the selected view.
 246                 TextView selectedFolderTextView = findViewById(R.id.spinner_item_textview);
 247
 248                 // Store the current folder name.
 249                 currentFolderName = selectedFolderTextView.getText().toString();
 250
 251                 // Update the list view.
 252                 updateBookmarksListView();
 253             }
 254
 255             @Override
 256             public void onNothingSelected(AdapterView<?> parent) {
 257                 // Do nothing.
 258             }
 259         });
 260
 261         // Get a handle for the bookmarks `ListView`.
 262         ListView bookmarksListView = findViewById(R.id.bookmarks_databaseview_listview);
 263
 264         // Get a `Cursor` with the current contents of the bookmarks database.
 265         bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarks();
 266
 267         // Setup a `CursorAdapter` with `this` context.  `false` disables autoRequery.
 268         bookmarksCursorAdapter = new CursorAdapter(this, bookmarksCursor, false) {
 269             @Override
 270             public View newView(Context context, Cursor cursor, ViewGroup parent) {
 271                 // Inflate the individual item layout.  `false` does not attach it to the root.
 272                 return getLayoutInflater().inflate(R.layout.bookmarks_databaseview_item_linearlayout, parent, false);
 273             }
 274
 275             @Override
 276             public void bindView(View view, Context context, Cursor cursor) {
 277                 boolean isFolder = (cursor.getInt(cursor.getColumnIndex(BookmarksDatabaseHelper.IS_FOLDER)) == 1);
 278
 279                 // Get the database ID from the `Cursor` and display it in `bookmarkDatabaseIdTextView`.
 280                 int bookmarkDatabaseId = cursor.getInt(cursor.getColumnIndex(BookmarksDatabaseHelper._ID));
 281                 TextView bookmarkDatabaseIdTextView = view.findViewById(R.id.bookmarks_databaseview_database_id);
 282                 bookmarkDatabaseIdTextView.setText(String.valueOf(bookmarkDatabaseId));
 283
 284                 // Get the favorite icon byte array from the `Cursor`.
 285                 byte[] favoriteIconByteArray = cursor.getBlob(cursor.getColumnIndex(BookmarksDatabaseHelper.FAVORITE_ICON));
 286                 // Convert the byte array to a `Bitmap` beginning at the beginning at the first byte and ending at the last.
 287                 Bitmap favoriteIconBitmap = BitmapFactory.decodeByteArray(favoriteIconByteArray, 0, favoriteIconByteArray.length);
 288                 // Display the bitmap in `bookmarkFavoriteIcon`.
 289                 ImageView bookmarkFavoriteIcon = view.findViewById(R.id.bookmarks_databaseview_favorite_icon);
 290                 bookmarkFavoriteIcon.setImageBitmap(favoriteIconBitmap);
 291
 292                 // Get the bookmark name from the `Cursor` and display it in `bookmarkNameTextView`.
 293                 String bookmarkNameString = cursor.getString(cursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_NAME));
 294                 TextView bookmarkNameTextView = view.findViewById(R.id.bookmarks_databaseview_bookmark_name);
 295                 bookmarkNameTextView.setText(bookmarkNameString);
 296
 297                 // Make the font bold for folders.
 298                 if (isFolder) {
 299                     // The first argument is `null` prevent changing of the font.
 300                     bookmarkNameTextView.setTypeface(null, Typeface.BOLD);
 301                 } else {  // Reset the font to default.
 302                     bookmarkNameTextView.setTypeface(Typeface.DEFAULT);
 303                 }
 304
 305                 // Get the bookmark URL form the `Cursor` and display it in `bookmarkUrlTextView`.
 306                 String bookmarkUrlString = cursor.getString(cursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_URL));
 307                 TextView bookmarkUrlTextView = view.findViewById(R.id.bookmarks_databaseview_bookmark_url);
 308                 bookmarkUrlTextView.setText(bookmarkUrlString);
 309
 310                 // Hide the URL if the bookmark is a folder.
 311                 if (isFolder) {
 312                     bookmarkUrlTextView.setVisibility(View.GONE);
 313                 } else {
 314                     bookmarkUrlTextView.setVisibility(View.VISIBLE);
 315                 }
 316
 317                 // Get the display order from the `Cursor` and display it in `bookmarkDisplayOrderTextView`.
 318                 int bookmarkDisplayOrder = cursor.getInt(cursor.getColumnIndex(BookmarksDatabaseHelper.DISPLAY_ORDER));
 319                 TextView bookmarkDisplayOrderTextView = view.findViewById(R.id.bookmarks_databaseview_display_order);
 320                 bookmarkDisplayOrderTextView.setText(String.valueOf(bookmarkDisplayOrder));
 321
 322                 // Get the parent folder from the `Cursor` and display it in `bookmarkParentFolder`.
 323                 String bookmarkParentFolder = cursor.getString(cursor.getColumnIndex(BookmarksDatabaseHelper.PARENT_FOLDER));
 324                 ImageView parentFolderImageView = view.findViewById(R.id.bookmarks_databaseview_parent_folder_icon);
 325                 TextView bookmarkParentFolderTextView = view.findViewById(R.id.bookmarks_databaseview_parent_folder);
 326
 327                 // Make the folder name gray if it is the home folder.
 328                 if (bookmarkParentFolder.isEmpty()) {
 329                     parentFolderImageView.setImageDrawable(ContextCompat.getDrawable(getApplicationContext(), R.drawable.folder_gray));
 330                     bookmarkParentFolderTextView.setText(R.string.home_folder);
 331                     bookmarkParentFolderTextView.setTextColor(ContextCompat.getColor(getApplicationContext(), R.color.gray_500));
 332                 } else {
 333                     parentFolderImageView.setImageDrawable(ContextCompat.getDrawable(getApplicationContext(), R.drawable.folder_dark_blue));
 334                     bookmarkParentFolderTextView.setText(bookmarkParentFolder);
 335
 336                     // Set the text color according to the theme.
 337                     if (darkTheme) {
 338                         bookmarkParentFolderTextView.setTextColor(ContextCompat.getColor(getApplicationContext(), R.color.gray_300));
 339                     } else {
 340                         bookmarkParentFolderTextView.setTextColor(ContextCompat.getColor(getApplicationContext(), R.color.black));
 341                     }
 342                 }
 343             }
 344         };
 345
 346         // Update the ListView.
 347         bookmarksListView.setAdapter(bookmarksCursorAdapter);
 348
 349         // Set the current folder database ID.
 350         currentFolderDatabaseId = ALL_FOLDERS_DATABASE_ID;
 351
 352         // Set a listener to edit a bookmark when it is tapped.
 353         bookmarksListView.setOnItemClickListener((AdapterView<?> parent, View view, int position, long id) -> {
 354             // Convert the database ID to an int.
 355             int databaseId = (int) id;
 356
 357             // Show the edit bookmark or edit bookmark folder dialog.
 358             if (bookmarksDatabaseHelper.isFolder(databaseId)) {
 359                 // Save the current folder name, which is used in `onSaveBookmarkFolder()`.
 360                 oldFolderNameString = bookmarksCursor.getString(bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper.BOOKMARK_NAME));
 361
 362                 // Show the edit bookmark folder dialog.
 363                 DialogFragment editBookmarkFolderDatabaseViewDialog = EditBookmarkFolderDatabaseViewDialog.folderDatabaseId(databaseId, favoriteIconBitmap);
 364                 editBookmarkFolderDatabaseViewDialog.show(getSupportFragmentManager(), getResources().getString(R.string.edit_folder));
 365             } else {
 366                 // Show the edit bookmark dialog.
 367                 DialogFragment editBookmarkDatabaseViewDialog = EditBookmarkDatabaseViewDialog.bookmarkDatabaseId(databaseId, favoriteIconBitmap);
 368                 editBookmarkDatabaseViewDialog.show(getSupportFragmentManager(), getResources().getString(R.string.edit_bookmark));
 369             }
 370         });
 371
 372         // Handle long presses on the list view.
 373         bookmarksListView.setMultiChoiceModeListener(new AbsListView.MultiChoiceModeListener() {
 374             // Instantiate the common variables.
 375             MenuItem selectAllMenuItem;
 376             MenuItem deleteMenuItem;
 377             boolean deletingBookmarks;
 378
 379             @Override
 380             public boolean onCreateActionMode(ActionMode mode, Menu menu) {
 381                 // Inflate the menu for the contextual app bar.
 382                 getMenuInflater().inflate(R.menu.bookmarks_databaseview_context_menu, menu);
 383
 384                 // Set the title.
 385                 mode.setTitle(R.string.bookmarks);
 386
 387                 // Get handles for the menu items.
 388                 selectAllMenuItem = menu.findItem(R.id.select_all);
 389                 deleteMenuItem = menu.findItem(R.id.delete);
 390
 391                 // Disable the delete menu item if a delete is pending.
 392                 deleteMenuItem.setEnabled(!deletingBookmarks);
 393
 394                 // Make it so.
 395                 return true;
 396             }
 397
 398             @Override
 399             public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
 400                 // Do nothing.
 401                 return false;
 402             }
 403
 404             @Override
 405             public void onItemCheckedStateChanged(ActionMode mode, int position, long id, boolean checked) {
 406                 // Calculate the number of selected bookmarks.
 407                 int numberOfSelectedBookmarks = bookmarksListView.getCheckedItemCount();
 408
 409                 // Adjust the ActionMode according to the number of selected bookmarks.
 410                 mode.setSubtitle(getString(R.string.selected) + "  " + numberOfSelectedBookmarks);
 411
 412                 // Do not show the select all menu item if all the bookmarks are already checked.
 413                 if (bookmarksListView.getCheckedItemCount() == bookmarksListView.getCount()) {
 414                     selectAllMenuItem.setVisible(false);
 415                 } else {
 416                     selectAllMenuItem.setVisible(true);
 417                 }
 418
 419                 // Convert the database ID to an int.
 420                 int databaseId = (int) id;
 421
 422                 // If a folder was selected, also select all the contents.
 423                 if (checked && bookmarksDatabaseHelper.isFolder(databaseId)) {
 424                     selectAllBookmarksInFolder(databaseId);
 425                 }
 426
 427                 // Do not allow a bookmark to be deselected if the folder is selected.
 428                 if (!checked) {
 429                     // Get the folder name.
 430                     String folderName = bookmarksDatabaseHelper.getParentFolderName((int) id);
 431
 432                     // If the bookmark is not in the root folder, check to see if the folder is selected.
 433                     if (!folderName.isEmpty()) {
 434                         // Get the database ID of the folder.
 435                         int folderDatabaseId = bookmarksDatabaseHelper.getFolderDatabaseId(folderName);
 436
 437                         // Move the bookmarks cursor to the first position.
 438                         bookmarksCursor.moveToFirst();
 439
 440                         // Initialize the folder position variable.
 441                         int folderPosition = -1;
 442
 443                         // Get the position of the folder in the bookmarks cursor.
 444                         while ((folderPosition < 0) && (bookmarksCursor.getPosition() < bookmarksCursor.getCount())) {
 445                             // Check if the folder database ID matches the bookmark database ID.
 446                             if (folderDatabaseId == bookmarksCursor.getInt((bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper._ID)))) {
 447                                 // Get the folder position.
 448                                 folderPosition = bookmarksCursor.getPosition();
 449
 450                                 // Check if the folder is selected.
 451                                 if (bookmarksListView.isItemChecked(folderPosition)) {
 452                                     // Reselect the bookmark.
 453                                     bookmarksListView.setItemChecked(position, true);
 454
 455                                     // Display a snackbar explaining why the bookmark cannot be deselected.
 456                                     Snackbar.make(bookmarksListView, R.string.cannot_deselect_bookmark, Snackbar.LENGTH_LONG).show();
 457                                 }
 458                             }
 459
 460                             // Increment the bookmarks cursor.
 461                             bookmarksCursor.moveToNext();
 462                         }
 463                     }
 464                 }
 465             }
 466
 467             @Override
 468             public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
 469                 switch (item.getItemId()) {
 470                     case R.id.select_all:
 471                         // Get the total number of bookmarks.
 472                         int numberOfBookmarks = bookmarksListView.getCount();
 473
 474                         // Select them all.
 475                         for (int i = 0; i < numberOfBookmarks; i++) {
 476                             bookmarksListView.setItemChecked(i, true);
 477                         }
 478                         break;
 479
 480                     case R.id.delete:
 481                         // Set the deleting bookmarks flag, which prevents the delete menu item from being enabled until the current process finishes.
 482                         deletingBookmarks = true;
 483
 484                         // Get an array of the selected row IDs.
 485                         long[] selectedBookmarksIdsLongArray = bookmarksListView.getCheckedItemIds();
 486
 487                         // Get an array of checked bookmarks.  `.clone()` makes a copy that won't change if the list view is reloaded, which is needed for re-selecting the bookmarks on undelete.
 488                         SparseBooleanArray selectedBookmarksPositionsSparseBooleanArray = bookmarksListView.getCheckedItemPositions().clone();
 489
 490                         // Update the bookmarks cursor with the current contents of the bookmarks database except for the specified database IDs.
 491                         switch (currentFolderDatabaseId) {
 492                             // Get a cursor with all the folders.
 493                             case ALL_FOLDERS_DATABASE_ID:
 494                                 if (sortByDisplayOrder) {
 495                                     bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksByDisplayOrderExcept(selectedBookmarksIdsLongArray);
 496                                 } else {
 497                                     bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksExcept(selectedBookmarksIdsLongArray);
 498                                 }
 499                                 break;
 500
 501                             // Get a cursor for the home folder.
 502                             case HOME_FOLDER_DATABASE_ID:
 503                                 if (sortByDisplayOrder) {
 504                                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarksByDisplayOrderExcept(selectedBookmarksIdsLongArray, "");
 505                                 } else {
 506                                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarksExcept(selectedBookmarksIdsLongArray, "");
 507                                 }
 508                                 break;
 509
 510                             // Display the selected folder.
 511                             default:
 512                                 // Get a cursor for the selected folder.
 513                                 if (sortByDisplayOrder) {
 514                                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarksByDisplayOrderExcept(selectedBookmarksIdsLongArray, currentFolderName);
 515                                 } else {
 516                                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarksExcept(selectedBookmarksIdsLongArray, currentFolderName);
 517                                 }
 518                         }
 519
 520                         // Update the list view.
 521                         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 522
 523                         // Create a Snackbar with the number of deleted bookmarks.
 524                         bookmarksDeletedSnackbar = Snackbar.make(findViewById(R.id.bookmarks_databaseview_coordinatorlayout),
 525                                 getString(R.string.bookmarks_deleted) + "  " + selectedBookmarksIdsLongArray.length, Snackbar.LENGTH_LONG)
 526                                 .setAction(R.string.undo, view -> {
 527                                     // Do nothing because everything will be handled by `onDismissed()` below.
 528                                 })
 529                                 .addCallback(new Snackbar.Callback() {
 530                                     @SuppressLint("SwitchIntDef")  // Ignore the lint warning about not handling the other possible events as they are covered by `default:`.
 531                                     @Override
 532                                     public void onDismissed(Snackbar snackbar, int event) {
 533                                         if (event == Snackbar.Callback.DISMISS_EVENT_ACTION) {  // The user pushed the undo button.
 534                                             // Update the bookmarks list view with the current contents of the bookmarks database, including the "deleted bookmarks.
 535                                             updateBookmarksListView();
 536
 537                                             // Re-select the previously selected bookmarks.
 538                                             for (int i = 0; i < selectedBookmarksPositionsSparseBooleanArray.size(); i++) {
 539                                                 bookmarksListView.setItemChecked(selectedBookmarksPositionsSparseBooleanArray.keyAt(i), true);
 540                                             }
 541                                         } else {  // The Snackbar was dismissed without the undo button being pushed.
 542                                             // Delete each selected bookmark.
 543                                             for (long databaseIdLong : selectedBookmarksIdsLongArray) {
 544                                                 // Convert `databaseIdLong` to an int.
 545                                                 int databaseIdInt = (int) databaseIdLong;
 546
 547                                                 // Delete the selected bookmark.
 548                                                 bookmarksDatabaseHelper.deleteBookmark(databaseIdInt);
 549                                             }
 550                                         }
 551
 552                                         // Reset the deleting bookmarks flag.
 553                                         deletingBookmarks = false;
 554
 555                                         // Enable the delete menu item.
 556                                         deleteMenuItem.setEnabled(true);
 557
 558                                         // Close the activity if back has been pressed.
 559                                         if (closeActivityAfterDismissingSnackbar) {
 560                                             onBackPressed();
 561                                         }
 562                                     }
 563                                 });
 564
 565                         // Show the Snackbar.
 566                         bookmarksDeletedSnackbar.show();
 567                         break;
 568                 }
 569
 570                 // Consume the click.
 571                 return false;
 572             }
 573
 574             @Override
 575             public void onDestroyActionMode(ActionMode mode) {
 576                 // Do nothing.
 577             }
 578         });
 579     }
 580
 581     @Override
 582     public boolean onCreateOptionsMenu(Menu menu) {
 583         // Inflate the menu.
 584         getMenuInflater().inflate(R.menu.bookmarks_databaseview_options_menu, menu);
 585
 586         // Success.
 587         return true;
 588     }
 589
 590     @Override
 591     public boolean onOptionsItemSelected(MenuItem menuItem) {
 592         // Get a handle for the shared preferences.
 593         SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
 594
 595         // Get the theme preferences.
 596         boolean darkTheme = sharedPreferences.getBoolean("dark_theme", false);
 597
 598         // Get the ID of the menu item that was selected.
 599         int menuItemId = menuItem.getItemId();
 600
 601         // Run the command that corresponds to the selected menu item.
 602         switch (menuItemId) {
 603             case android.R.id.home:  // The home arrow is identified as `android.R.id.home`, not just `R.id.home`.
 604                 // Exit the activity.
 605                 onBackPressed();
 606                 break;
 607
 608             case R.id.options_menu_sort:
 609                 // Update the sort by display order tracker.
 610                 sortByDisplayOrder = !sortByDisplayOrder;
 611
 612                 // Get a handle for the bookmarks `ListView`.
 613                 ListView bookmarksListView = findViewById(R.id.bookmarks_databaseview_listview);
 614
 615                 // Update the icon and display a snackbar.
 616                 if (sortByDisplayOrder) {  // Sort by display order.
 617                     // Update the icon according to the theme.
 618                     if (darkTheme) {
 619                         menuItem.setIcon(R.drawable.sort_selected_dark);
 620                     } else {
 621                         menuItem.setIcon(R.drawable.sort_selected_light);
 622                     }
 623
 624                     // Display a Snackbar indicating the current sort type.
 625                     Snackbar.make(bookmarksListView, R.string.sorted_by_display_order, Snackbar.LENGTH_SHORT).show();
 626                 } else {  // Sort by database id.
 627                     // Update the icon according to the theme.
 628                     if (darkTheme) {
 629                         menuItem.setIcon(R.drawable.sort_dark);
 630                     } else {
 631                         menuItem.setIcon(R.drawable.sort_light);
 632                     }
 633
 634                     // Display a Snackbar indicating the current sort type.
 635                     Snackbar.make(bookmarksListView, R.string.sorted_by_database_id, Snackbar.LENGTH_SHORT).show();
 636                 }
 637
 638                 // Update the list view.
 639                 updateBookmarksListView();
 640                 break;
 641         }
 642         return true;
 643     }
 644
 645     @Override
 646     public void onBackPressed() {
 647         // Check to see if a snackbar is currently displayed.  If so, it must be closed before existing so that a pending delete is completed before reloading the list view in the bookmarks activity.
 648         if ((bookmarksDeletedSnackbar != null) && bookmarksDeletedSnackbar.isShown()) { // Close the bookmarks deleted snackbar before going home.
 649             // Set the close flag.
 650             closeActivityAfterDismissingSnackbar = true;
 651
 652             // Dismiss the snackbar.
 653             bookmarksDeletedSnackbar.dismiss();
 654         } else {  // Go home immediately.
 655             // Update the current folder in the bookmarks activity.
 656             if ((currentFolderDatabaseId == ALL_FOLDERS_DATABASE_ID) || (currentFolderDatabaseId == HOME_FOLDER_DATABASE_ID)) {  // All folders or the the home folder are currently displayed.
 657                 // Load the home folder.
 658                 BookmarksActivity.currentFolder = "";
 659             } else {  // A subfolder is currently displayed.
 660                 // Load the current folder.
 661                 BookmarksActivity.currentFolder = currentFolderName;
 662             }
 663
 664             // Reload the bookmarks list view when returning to the bookmarks activity.
 665             BookmarksActivity.restartFromBookmarksDatabaseViewActivity = true;
 666
 667             // Exit the bookmarks database view activity.
 668             super.onBackPressed();
 669         }
 670     }
 671
 672     private void updateBookmarksListView() {
 673         // Populate the bookmarks list view based on the spinner selection.
 674         switch (currentFolderDatabaseId) {
 675             // Get a cursor with all the folders.
 676             case ALL_FOLDERS_DATABASE_ID:
 677                 if (sortByDisplayOrder) {
 678                     bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarksByDisplayOrder();
 679                 } else {
 680                     bookmarksCursor = bookmarksDatabaseHelper.getAllBookmarks();
 681                 }
 682                 break;
 683
 684             // Get a cursor for the home folder.
 685             case HOME_FOLDER_DATABASE_ID:
 686                 if (sortByDisplayOrder) {
 687                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarksByDisplayOrder("");
 688                 } else {
 689                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarks("");
 690                 }
 691                 break;
 692
 693             // Display the selected folder.
 694             default:
 695                 // Get a cursor for the selected folder.
 696                 if (sortByDisplayOrder) {
 697                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarksByDisplayOrder(currentFolderName);
 698                 } else {
 699                     bookmarksCursor = bookmarksDatabaseHelper.getBookmarks(currentFolderName);
 700                 }
 701         }
 702
 703         // Update the list view.
 704         bookmarksCursorAdapter.changeCursor(bookmarksCursor);
 705     }
 706
 707     private void selectAllBookmarksInFolder(int folderId) {
 708         // Get a handle for the bookmarks list view.
 709         ListView bookmarksListView = findViewById(R.id.bookmarks_databaseview_listview);
 710
 711         // Get the folder name.
 712         String folderName = bookmarksDatabaseHelper.getFolderName(folderId);
 713
 714         // Get a cursor with the contents of the folder.
 715         Cursor folderCursor = bookmarksDatabaseHelper.getBookmarks(folderName);
 716
 717         // Move to the beginning of the cursor.
 718         folderCursor.moveToFirst();
 719
 720         while (folderCursor.getPosition() < folderCursor.getCount()) {
 721             // Get the bookmark database ID.
 722             int bookmarkId = folderCursor.getInt(folderCursor.getColumnIndex(BookmarksDatabaseHelper._ID));
 723
 724             // Move the bookmarks cursor to the first position.
 725             bookmarksCursor.moveToFirst();
 726
 727             // Initialize the bookmark position variable.
 728             int bookmarkPosition = -1;
 729
 730             // Get the position of this bookmark in the bookmarks cursor.
 731             while ((bookmarkPosition < 0) && (bookmarksCursor.getPosition() < bookmarksCursor.getCount())) {
 732                 // Check if the bookmark IDs match.
 733                 if (bookmarkId == bookmarksCursor.getInt(bookmarksCursor.getColumnIndex(BookmarksDatabaseHelper._ID))) {
 734                     // Get the bookmark position.
 735                     bookmarkPosition = bookmarksCursor.getPosition();
 736
 737                     // If this bookmark is a folder, select all the bookmarks inside it.
 738                     if (bookmarksDatabaseHelper.isFolder(bookmarkId)) {
 739                         selectAllBookmarksInFolder(bookmarkId);
 740                     }
 741
 742                     // Select the bookmark.
 743                     bookmarksListView.setItemChecked(bookmarkPosition, true);
 744                 }
 745
 746                 // Increment the bookmarks cursor position.
 747                 bookmarksCursor.moveToNext();
 748             }
 749
 750             // Move to the next position.
 751             folderCursor.moveToNext();
 752         }
 753     }
 754
 755     @Override
 756     public void onSaveBookmark(DialogFragment dialogFragment, int selectedBookmarkDatabaseId, Bitmap favoriteIconBitmap) {
 757         // Get the dialog from the dialog fragment.
 758         Dialog dialog = dialogFragment.getDialog();
 759
 760         // Remove the incorrect lint warning below that the dialog might be null.
 761         assert dialog != null;
 762
 763         // Get handles for the views from dialog fragment.
 764         RadioButton currentBookmarkIconRadioButton = dialog.findViewById(R.id.edit_bookmark_current_icon_radiobutton);
 765         EditText editBookmarkNameEditText = dialog.findViewById(R.id.edit_bookmark_name_edittext);
 766         EditText editBookmarkUrlEditText = dialog.findViewById(R.id.edit_bookmark_url_edittext);
 767         Spinner folderSpinner = dialog.findViewById(R.id.edit_bookmark_folder_spinner);
 768         EditText displayOrderEditText = dialog.findViewById(R.id.edit_bookmark_display_order_edittext);
 769
 770         // Extract the bookmark information.
 771         String bookmarkNameString = editBookmarkNameEditText.getText().toString();
 772         String bookmarkUrlString = editBookmarkUrlEditText.getText().toString();
 773         int folderDatabaseId = (int) folderSpinner.getSelectedItemId();
 774         int displayOrderInt = Integer.parseInt(displayOrderEditText.getText().toString());
 775
 776         // Instantiate the parent folder name `String`.
 777         String parentFolderNameString;
 778
 779         // Set the parent folder name.
 780         if (folderDatabaseId == EditBookmarkDatabaseViewDialog.HOME_FOLDER_DATABASE_ID) {  // The home folder is selected.  Use `""`.
 781             parentFolderNameString = "";
 782         } else {  // Get the parent folder name from the database.
 783             parentFolderNameString = bookmarksDatabaseHelper.getFolderName(folderDatabaseId);
 784         }
 785
 786         // Update the bookmark.
 787         if (currentBookmarkIconRadioButton.isChecked()) {  // Update the bookmark without changing the favorite icon.
 788             bookmarksDatabaseHelper.updateBookmark(selectedBookmarkDatabaseId, bookmarkNameString, bookmarkUrlString, parentFolderNameString, displayOrderInt);
 789         } else {  // Update the bookmark using the `WebView` favorite icon.
 790             // Create a favorite icon byte array output stream.
 791             ByteArrayOutputStream newFavoriteIconByteArrayOutputStream = new ByteArrayOutputStream();
 792
 793             // Convert the favorite icon bitmap to a byte array.  `0` is for lossless compression (the only option for a PNG).
 794             favoriteIconBitmap.compress(Bitmap.CompressFormat.PNG, 0, newFavoriteIconByteArrayOutputStream);
 795
 796             // Convert the favorite icon byte array stream to a byte array.
 797             byte[] newFavoriteIconByteArray = newFavoriteIconByteArrayOutputStream.toByteArray();
 798
 799             //  Update the bookmark and the favorite icon.
 800             bookmarksDatabaseHelper.updateBookmark(selectedBookmarkDatabaseId, bookmarkNameString, bookmarkUrlString, parentFolderNameString, displayOrderInt, newFavoriteIconByteArray);
 801         }
 802
 803         // Update the list view.
 804         updateBookmarksListView();
 805     }
 806
 807     @Override
 808     public void onSaveBookmarkFolder(DialogFragment dialogFragment, int selectedBookmarkDatabaseId, Bitmap favoriteIconBitmap) {
 809         // Get the dialog from the dialog fragment.
 810         Dialog dialog = dialogFragment.getDialog();
 811
 812         // Remove the incorrect lint warning below that the dialog might be null.
 813         assert dialog != null;
 814
 815         // Get handles for the views from dialog fragment.
 816         RadioButton currentBookmarkIconRadioButton = dialog.findViewById(R.id.edit_folder_current_icon_radiobutton);
 817         RadioButton defaultFolderIconRadioButton = dialog.findViewById(R.id.edit_folder_default_icon_radiobutton);
 818         ImageView defaultFolderIconImageView = dialog.findViewById(R.id.edit_folder_default_icon_imageview);
 819         EditText editBookmarkNameEditText = dialog.findViewById(R.id.edit_folder_name_edittext);
 820         Spinner parentFolderSpinner = dialog.findViewById(R.id.edit_folder_parent_folder_spinner);
 821         EditText displayOrderEditText = dialog.findViewById(R.id.edit_folder_display_order_edittext);
 822
 823         // Extract the folder information.
 824         String newFolderNameString = editBookmarkNameEditText.getText().toString();
 825         int parentFolderDatabaseId = (int) parentFolderSpinner.getSelectedItemId();
 826         int displayOrderInt = Integer.parseInt(displayOrderEditText.getText().toString());
 827
 828         // Instantiate the parent folder name `String`.
 829         String parentFolderNameString;
 830
 831         // Set the parent folder name.
 832         if (parentFolderDatabaseId == EditBookmarkFolderDatabaseViewDialog.HOME_FOLDER_DATABASE_ID) {  // The home folder is selected.  Use `""`.
 833             parentFolderNameString = "";
 834         } else {  // Get the parent folder name from the database.
 835             parentFolderNameString = bookmarksDatabaseHelper.getFolderName(parentFolderDatabaseId);
 836         }
 837
 838         // Update the folder.
 839         if (currentBookmarkIconRadioButton.isChecked()) {  // Update the folder without changing the favorite icon.
 840             bookmarksDatabaseHelper.updateFolder(selectedBookmarkDatabaseId, oldFolderNameString, newFolderNameString, parentFolderNameString, displayOrderInt);
 841         } else {  // Update the folder and the icon.
 842             // Create the new folder icon Bitmap.
 843             Bitmap folderIconBitmap;
 844
 845             // Populate the new folder icon bitmap.
 846             if (defaultFolderIconRadioButton.isChecked()) {
 847                 // Get the default folder icon drawable.
 848                 Drawable folderIconDrawable = defaultFolderIconImageView.getDrawable();
 849
 850                 // Convert the folder icon drawable to a bitmap drawable.
 851                 BitmapDrawable folderIconBitmapDrawable = (BitmapDrawable) folderIconDrawable;
 852
 853                 // Convert the folder icon bitmap drawable to a bitmap.
 854                 folderIconBitmap = folderIconBitmapDrawable.getBitmap();
 855             } else {  // Use the `WebView` favorite icon.
 856                 // Get a copy of the favorite icon bitmap.
 857                 folderIconBitmap = favoriteIconBitmap;
 858             }
 859
 860             // Create a folder icon byte array output stream.
 861             ByteArrayOutputStream newFolderIconByteArrayOutputStream = new ByteArrayOutputStream();
 862
 863             // Convert the folder icon bitmap to a byte array.  `0` is for lossless compression (the only option for a PNG).
 864             folderIconBitmap.compress(Bitmap.CompressFormat.PNG, 0, newFolderIconByteArrayOutputStream);
 865
 866             // Convert the folder icon byte array stream to a byte array.
 867             byte[] newFolderIconByteArray = newFolderIconByteArrayOutputStream.toByteArray();
 868
 869             //  Update the folder and the icon.
 870             bookmarksDatabaseHelper.updateFolder(selectedBookmarkDatabaseId, oldFolderNameString, newFolderNameString, parentFolderNameString, displayOrderInt, newFolderIconByteArray);
 871         }
 872
 873         // Update the list view.
 874         updateBookmarksListView();
 875     }
 876
 877     @Override
 878     public void onDestroy() {
 879         // Close the bookmarks cursor and database.
 880         bookmarksCursor.close();
 881         bookmarksDatabaseHelper.close();
 882
 883         // Run the default commands.
 884         super.onDestroy();
 885     }
 886 }