app/src/main/java/com/stoutner/privacybrowser/fragments/AboutTabFragment.java

   1 /*
   2  * Copyright © 2016-2018 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.fragments;
  21
  22 import android.annotation.SuppressLint;
  23 import android.content.Context;
  24 import android.content.pm.PackageManager;
  25 import android.content.pm.Signature;
  26 import android.os.Build;
  27 import android.os.Bundle;
  28 import android.support.annotation.NonNull;
  29 import android.support.v4.app.Fragment;
  30 import android.text.SpannableStringBuilder;
  31 import android.text.Spanned;
  32 import android.text.style.ForegroundColorSpan;
  33 import android.view.LayoutInflater;
  34 import android.view.View;
  35 import android.view.ViewGroup;
  36 import android.webkit.WebView;
  37 import android.widget.TextView;
  38
  39 import com.stoutner.privacybrowser.BuildConfig;
  40 import com.stoutner.privacybrowser.R;
  41 import com.stoutner.privacybrowser.activities.MainWebViewActivity;
  42
  43 import java.io.ByteArrayInputStream;
  44 import java.io.InputStream;
  45 import java.math.BigInteger;
  46 import java.security.Principal;
  47 import java.security.cert.CertificateException;
  48 import java.security.cert.CertificateFactory;
  49 import java.security.cert.X509Certificate;
  50 import java.text.DateFormat;
  51 import java.util.Date;
  52
  53 public class AboutTabFragment extends Fragment {
  54     private int tabNumber;
  55
  56     // Store the tab number in the arguments bundle.
  57     public static AboutTabFragment createTab(int tab) {
  58         // Create a bundle.
  59         Bundle bundle = new Bundle();
  60
  61         // Store the tab number in the bundle.
  62         bundle.putInt("Tab", tab);
  63
  64         // Add the bundle to the fragment.
  65         AboutTabFragment aboutTabFragment = new AboutTabFragment();
  66         aboutTabFragment.setArguments(bundle);
  67
  68         // Return the new fragment.
  69         return aboutTabFragment;
  70     }
  71
  72     @Override
  73     public void onCreate(Bundle savedInstanceState) {
  74         // Run the default commands.
  75         super.onCreate(savedInstanceState);
  76
  77         // Remove the lint warning that `getArguments()` might be null.
  78         assert getArguments() != null;
  79
  80         // Store the tab number in a class variable.
  81         tabNumber = getArguments().getInt("Tab");
  82     }
  83
  84     @Override
  85     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  86         // Create a tab layout view.
  87         View tabLayout;
  88
  89         // Get a handle for the context and assert that it isn't null.
  90         Context context = getContext();
  91         assert context != null;
  92
  93         // Load the tabs.  Tab numbers start at 0.
  94         if (tabNumber == 0) {  // Load the about tab.
  95             // Setting false at the end of inflater.inflate does not attach the inflated layout as a child of container.  The fragment will take care of attaching the root automatically.
  96             tabLayout = inflater.inflate(R.layout.about_tab_version, container, false);
  97
  98             // Get handles for the `TextViews`.
  99             TextView versionTextView = tabLayout.findViewById(R.id.version);
 100             TextView brandTextView = tabLayout.findViewById(R.id.brand);
 101             TextView manufacturerTextView = tabLayout.findViewById(R.id.manufacturer);
 102             TextView modelTextView = tabLayout.findViewById(R.id.model);
 103             TextView deviceTextView = tabLayout.findViewById(R.id.device);
 104             TextView bootloaderTextView = tabLayout.findViewById(R.id.bootloader);
 105             TextView radioTextView = tabLayout.findViewById(R.id.radio);
 106             TextView androidTextView = tabLayout.findViewById(R.id.android);
 107             TextView securityPatchTextView = tabLayout.findViewById(R.id.security_patch);
 108             TextView buildTextView = tabLayout.findViewById(R.id.build);
 109             TextView webViewTextView = tabLayout.findViewById(R.id.webview);
 110             TextView orbotTextView = tabLayout.findViewById(R.id.orbot);
 111             TextView openKeychainTextView = tabLayout.findViewById(R.id.open_keychain);
 112             TextView easyListTextView = tabLayout.findViewById(R.id.easylist);
 113             TextView easyPrivacyTextView = tabLayout.findViewById(R.id.easyprivacy);
 114             TextView fanboyAnnoyanceTextView = tabLayout.findViewById(R.id.fanboy_annoyance);
 115             TextView fanboySocialTextView = tabLayout.findViewById(R.id.fanboy_social);
 116             TextView ultraPrivacyTextView = tabLayout.findViewById(R.id.ultraprivacy);
 117             TextView certificateIssuerDNTextView = tabLayout.findViewById(R.id.certificate_issuer_dn);
 118             TextView certificateSubjectDNTextView = tabLayout.findViewById(R.id.certificate_subject_dn);
 119             TextView certificateStartDateTextView = tabLayout.findViewById(R.id.certificate_start_date);
 120             TextView certificateEndDateTextView = tabLayout.findViewById(R.id.certificate_end_date);
 121             TextView certificateVersionTextView = tabLayout.findViewById(R.id.certificate_version);
 122             TextView certificateSerialNumberTextView = tabLayout.findViewById(R.id.certificate_serial_number);
 123             TextView certificateSignatureAlgorithmTextView = tabLayout.findViewById(R.id.certificate_signature_algorithm);
 124
 125             // Setup the labels.
 126             String version = getString(R.string.version) + " " + BuildConfig.VERSION_NAME + " (" + getString(R.string.version_code) + " " + Integer.toString(BuildConfig.VERSION_CODE) + ")";
 127             String brandLabel = getString(R.string.brand) + "  ";
 128             String manufacturerLabel = getString(R.string.manufacturer) + "  ";
 129             String modelLabel = getString(R.string.model) + "  ";
 130             String deviceLabel = getString(R.string.device) + "  ";
 131             String bootloaderLabel = getString(R.string.bootloader) + "  ";
 132             String androidLabel = getString(R.string.android) + "  ";
 133             String buildLabel = getString(R.string.build) + "  ";
 134             String webViewLabel = getString(R.string.webview) + "  ";
 135             String easyListLabel = getString(R.string.easylist_label) + "  ";
 136             String easyPrivacyLabel = getString(R.string.easyprivacy_label) + "  ";
 137             String fanboyAnnoyanceLabel = getString(R.string.fanboy_annoyance_label) + "  ";
 138             String fanboySocialLabel = getString(R.string.fanboy_social_label) + "  ";
 139             String ultraPrivacyLabel = getString(R.string.ultraprivacy_label) + "  ";
 140             String issuerDNLabel = getString(R.string.issuer_dn) + "  ";
 141             String subjectDNLabel = getString(R.string.subject_dn) + "  ";
 142             String startDateLabel = getString(R.string.start_date) + "  ";
 143             String endDateLabel = getString(R.string.end_date) + "  ";
 144             String certificateVersionLabel = getString(R.string.certificate_version) + "  ";
 145             String serialNumberLabel = getString(R.string.serial_number) + "  ";
 146             String signatureAlgorithmLabel = getString(R.string.signature_algorithm) + "  ";
 147
 148             // `webViewLayout` is only used to get the default user agent from `bare_webview`.  It is not used to render content on the screen.
 149             View webViewLayout = inflater.inflate(R.layout.bare_webview, container, false);
 150             WebView tabLayoutWebView = webViewLayout.findViewById(R.id.bare_webview);
 151             String userAgentString =  tabLayoutWebView.getSettings().getUserAgentString();
 152
 153             // Get the device's information and store it in strings.
 154             String brand = Build.BRAND;
 155             String manufacturer = Build.MANUFACTURER;
 156             String model = Build.MODEL;
 157             String device = Build.DEVICE;
 158             String bootloader = Build.BOOTLOADER;
 159             String radio = Build.getRadioVersion();
 160             String android = Build.VERSION.RELEASE + " (" + getString(R.string.api) + " " + Integer.toString(Build.VERSION.SDK_INT) + ")";
 161             String build = Build.DISPLAY;
 162             // Select the substring that begins after `Chrome/` and goes until the next ` `.
 163             String webView = userAgentString.substring(userAgentString.indexOf("Chrome/") + 7, userAgentString.indexOf(" ", userAgentString.indexOf("Chrome/")));
 164
 165             // Get the Orbot version name if Orbot is installed.
 166             String orbot;
 167             try {
 168                 // Store the version name.
 169                 orbot = context.getPackageManager().getPackageInfo("org.torproject.android", 0).versionName;
 170             } catch (PackageManager.NameNotFoundException exception) {  // Orbot is not installed.
 171                 orbot = "";
 172             }
 173
 174             // Get the OpenKeychain version name if it is installed.
 175             String openKeychain;
 176             try {
 177                 // Store the version name.
 178                 openKeychain = context.getPackageManager().getPackageInfo("org.sufficientlysecure.keychain", 0).versionName;
 179             } catch (PackageManager.NameNotFoundException exception) {  // OpenKeychain is not installed.
 180                 openKeychain = "";
 181             }
 182
 183             // Create a `SpannableStringBuilder` for the hardware and software `TextViews` that needs multiple colors of text.
 184             SpannableStringBuilder brandStringBuilder = new SpannableStringBuilder(brandLabel + brand);
 185             SpannableStringBuilder manufacturerStringBuilder = new SpannableStringBuilder(manufacturerLabel + manufacturer);
 186             SpannableStringBuilder modelStringBuilder = new SpannableStringBuilder(modelLabel + model);
 187             SpannableStringBuilder deviceStringBuilder = new SpannableStringBuilder(deviceLabel + device);
 188             SpannableStringBuilder bootloaderStringBuilder = new SpannableStringBuilder(bootloaderLabel + bootloader);
 189             SpannableStringBuilder androidStringBuilder = new SpannableStringBuilder(androidLabel + android);
 190             SpannableStringBuilder buildStringBuilder = new SpannableStringBuilder(buildLabel + build);
 191             SpannableStringBuilder webViewStringBuilder = new SpannableStringBuilder(webViewLabel + webView);
 192             SpannableStringBuilder easyListStringBuilder = new SpannableStringBuilder(easyListLabel + MainWebViewActivity.easyListVersion);
 193             SpannableStringBuilder easyPrivacyStringBuilder = new SpannableStringBuilder(easyPrivacyLabel + MainWebViewActivity.easyPrivacyVersion);
 194             SpannableStringBuilder fanboyAnnoyanceStringBuilder = new SpannableStringBuilder(fanboyAnnoyanceLabel + MainWebViewActivity.fanboysAnnoyanceVersion);
 195             SpannableStringBuilder fanboySocialStringBuilder = new SpannableStringBuilder(fanboySocialLabel + MainWebViewActivity.fanboysSocialVersion);
 196             SpannableStringBuilder ultraPrivacyStringBuilder = new SpannableStringBuilder(ultraPrivacyLabel + MainWebViewActivity.ultraPrivacyVersion);
 197
 198             // Create the `blueColorSpan` variable.
 199             ForegroundColorSpan blueColorSpan;
 200
 201             // Set `blueColorSpan` according to the theme.  We have to use the deprecated `getColor()` until API >= 23.
 202             if (MainWebViewActivity.darkTheme) {
 203                 //noinspection deprecation
 204                 blueColorSpan = new ForegroundColorSpan(getResources().getColor(R.color.blue_400));
 205             } else {
 206                 //noinspection deprecation
 207                 blueColorSpan = new ForegroundColorSpan(getResources().getColor(R.color.blue_700));
 208             }
 209
 210             // Setup the spans to display the device information in blue.  `SPAN_INCLUSIVE_INCLUSIVE` allows the span to grow in either direction.
 211             brandStringBuilder.setSpan(blueColorSpan, brandLabel.length(), brandStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 212             manufacturerStringBuilder.setSpan(blueColorSpan, manufacturerLabel.length(), manufacturerStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 213             modelStringBuilder.setSpan(blueColorSpan, modelLabel.length(), modelStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 214             deviceStringBuilder.setSpan(blueColorSpan, deviceLabel.length(), deviceStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 215             bootloaderStringBuilder.setSpan(blueColorSpan, bootloaderLabel.length(), bootloaderStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 216             androidStringBuilder.setSpan(blueColorSpan, androidLabel.length(), androidStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 217             buildStringBuilder.setSpan(blueColorSpan, buildLabel.length(), buildStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 218             webViewStringBuilder.setSpan(blueColorSpan, webViewLabel.length(), webViewStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 219             easyListStringBuilder.setSpan(blueColorSpan, easyListLabel.length(), easyListStringBuilder.length(), Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
 220             easyPrivacyStringBuilder.setSpan(blueColorSpan, easyPrivacyLabel.length(), easyPrivacyStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 221             fanboyAnnoyanceStringBuilder.setSpan(blueColorSpan, fanboyAnnoyanceLabel.length(), fanboyAnnoyanceStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 222             fanboySocialStringBuilder.setSpan(blueColorSpan, fanboySocialLabel.length(), fanboySocialStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 223             ultraPrivacyStringBuilder.setSpan(blueColorSpan, ultraPrivacyLabel.length(), ultraPrivacyStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 224
 225             // Display the strings in the text boxes.
 226             versionTextView.setText(version);
 227             brandTextView.setText(brandStringBuilder);
 228             manufacturerTextView.setText(manufacturerStringBuilder);
 229             modelTextView.setText(modelStringBuilder);
 230             deviceTextView.setText(deviceStringBuilder);
 231             bootloaderTextView.setText(bootloaderStringBuilder);
 232             androidTextView.setText(androidStringBuilder);
 233             buildTextView.setText(buildStringBuilder);
 234             webViewTextView.setText(webViewStringBuilder);
 235             easyListTextView.setText(easyListStringBuilder);
 236             easyPrivacyTextView.setText(easyPrivacyStringBuilder);
 237             fanboyAnnoyanceTextView.setText(fanboyAnnoyanceStringBuilder);
 238             fanboySocialTextView.setText(fanboySocialStringBuilder);
 239             ultraPrivacyTextView.setText(ultraPrivacyStringBuilder);
 240
 241             // Build.VERSION.SECURITY_PATCH is only available for SDK_INT >= 23.
 242             if (Build.VERSION.SDK_INT >= 23) {
 243                 String securityPatchLabel = getString(R.string.security_patch) + "  ";
 244                 String securityPatch = Build.VERSION.SECURITY_PATCH;
 245                 SpannableStringBuilder securityPatchStringBuilder = new SpannableStringBuilder(securityPatchLabel + securityPatch);
 246                 securityPatchStringBuilder.setSpan(blueColorSpan, securityPatchLabel.length(), securityPatchStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 247                 securityPatchTextView.setText(securityPatchStringBuilder);
 248             } else {  // SDK_INT < 23.
 249                 securityPatchTextView.setVisibility(View.GONE);
 250             }
 251
 252             // Only populate the radio TextView if there is a radio in the device.
 253             if (!radio.isEmpty()) {
 254                 String radioLabel = getString(R.string.radio) + "  ";
 255                 SpannableStringBuilder radioStringBuilder = new SpannableStringBuilder(radioLabel + radio);
 256                 radioStringBuilder.setSpan(blueColorSpan, radioLabel.length(), radioStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 257                 radioTextView.setText(radioStringBuilder);
 258             } else {  // This device does not have a radio.
 259                 radioTextView.setVisibility(View.GONE);
 260             }
 261
 262             // Only populate the Orbot TextView if it is installed.
 263             if (!orbot.isEmpty()) {
 264                 String orbotLabel = getString(R.string.orbot) + "  ";
 265                 SpannableStringBuilder orbotStringBuilder = new SpannableStringBuilder(orbotLabel + orbot);
 266                 orbotStringBuilder.setSpan(blueColorSpan, orbotLabel.length(), orbotStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 267                 orbotTextView.setText(orbotStringBuilder);
 268             } else {  // Orbot is not installed.
 269                 orbotTextView.setVisibility(View.GONE);
 270             }
 271
 272             // Only populate the EasyKeychain TextView if it is installed.
 273             if (!openKeychain.isEmpty()) {
 274                 String openKeychainlabel = getString(R.string.open_keychain) + "  ";
 275                 SpannableStringBuilder openKeychainStringBuilder = new SpannableStringBuilder(openKeychainlabel + openKeychain);
 276                 openKeychainStringBuilder.setSpan(blueColorSpan, openKeychainlabel.length(), openKeychainStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 277                 openKeychainTextView.setText(openKeychainStringBuilder);
 278             } else {  //OpenKeychain is not installed.
 279                 openKeychainTextView.setVisibility(View.GONE);
 280             }
 281
 282             // Display the package signature.
 283             try {
 284                 // Get the first package signature.  Suppress the lint warning about the need to be careful in implementing comparison of certificates for security purposes.
 285                 @SuppressLint("PackageManagerGetSignatures") Signature packageSignature = getContext().getPackageManager().getPackageInfo(getContext().getPackageName(), PackageManager.GET_SIGNATURES).signatures[0];
 286
 287                 // Convert the signature to a `byte[]` `InputStream`.
 288                 InputStream certificateByteArrayInputStream = new ByteArrayInputStream(packageSignature.toByteArray());
 289
 290                 // Display the certificate information on the screen.
 291                 try {
 292                     // Instantiate a `CertificateFactory`.
 293                     CertificateFactory certificateFactory = CertificateFactory.getInstance("X509");
 294
 295                     // Generate an `X509Certificate`.
 296                     X509Certificate x509Certificate = (X509Certificate) certificateFactory.generateCertificate(certificateByteArrayInputStream);
 297
 298                     // Store the individual sections of the certificate that we are interested in.
 299                     Principal issuerDNPrincipal = x509Certificate.getIssuerDN();
 300                     Principal subjectDNPrincipal = x509Certificate.getSubjectDN();
 301                     Date startDate = x509Certificate.getNotBefore();
 302                     Date endDate = x509Certificate.getNotAfter();
 303                     int certificateVersion = x509Certificate.getVersion();
 304                     BigInteger serialNumberBigInteger = x509Certificate.getSerialNumber();
 305                     String signatureAlgorithmNameString = x509Certificate.getSigAlgName();
 306
 307                     // Create a `SpannableStringBuilder` for each `TextView` that needs multiple colors of text.
 308                     SpannableStringBuilder issuerDNStringBuilder = new SpannableStringBuilder(issuerDNLabel + issuerDNPrincipal.toString());
 309                     SpannableStringBuilder subjectDNStringBuilder = new SpannableStringBuilder(subjectDNLabel + subjectDNPrincipal.toString());
 310                     SpannableStringBuilder startDateStringBuilder = new SpannableStringBuilder(startDateLabel + DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.LONG).format(startDate));
 311                     SpannableStringBuilder endDataStringBuilder = new SpannableStringBuilder(endDateLabel + DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.LONG).format(endDate));
 312                     SpannableStringBuilder certificateVersionStringBuilder = new SpannableStringBuilder(certificateVersionLabel + certificateVersion);
 313                     SpannableStringBuilder serialNumberStringBuilder = new SpannableStringBuilder(serialNumberLabel + serialNumberBigInteger);
 314                     SpannableStringBuilder signatureAlgorithmStringBuilder = new SpannableStringBuilder(signatureAlgorithmLabel + signatureAlgorithmNameString);
 315
 316                     // Setup the spans to display the device information in blue.  `SPAN_INCLUSIVE_INCLUSIVE` allows the span to grow in either direction.
 317                     issuerDNStringBuilder.setSpan(blueColorSpan, issuerDNLabel.length(), issuerDNStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 318                     subjectDNStringBuilder.setSpan(blueColorSpan, subjectDNLabel.length(), subjectDNStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 319                     startDateStringBuilder.setSpan(blueColorSpan, startDateLabel.length(), startDateStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 320                     endDataStringBuilder.setSpan(blueColorSpan, endDateLabel.length(), endDataStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 321                     certificateVersionStringBuilder.setSpan(blueColorSpan, certificateVersionLabel.length(), certificateVersionStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 322                     serialNumberStringBuilder.setSpan(blueColorSpan, serialNumberLabel.length(), serialNumberStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 323                     signatureAlgorithmStringBuilder.setSpan(blueColorSpan, signatureAlgorithmLabel.length(), signatureAlgorithmStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 324
 325                     // Display the strings in the text boxes.
 326                     certificateIssuerDNTextView.setText(issuerDNStringBuilder);
 327                     certificateSubjectDNTextView.setText(subjectDNStringBuilder);
 328                     certificateStartDateTextView.setText(startDateStringBuilder);
 329                     certificateEndDateTextView.setText(endDataStringBuilder);
 330                     certificateVersionTextView.setText(certificateVersionStringBuilder);
 331                     certificateSerialNumberTextView.setText(serialNumberStringBuilder);
 332                     certificateSignatureAlgorithmTextView.setText(signatureAlgorithmStringBuilder);
 333                 } catch (CertificateException e) {
 334                     // Do nothing if there is a certificate error.
 335                 }
 336             } catch (PackageManager.NameNotFoundException e) {
 337                 // Do nothing if `PackageManager` says Privacy Browser isn't installed.
 338             }
 339         } else { // load a `WebView` for all the other tabs.  Tab numbers start at 0.
 340             // Setting false at the end of inflater.inflate does not attach the inflated layout as a child of container.  The fragment will take care of attaching the root automatically.
 341             tabLayout = inflater.inflate(R.layout.bare_webview, container, false);
 342
 343             // Get a handle for `tabWebView`.
 344             WebView tabWebView = (WebView) tabLayout;
 345
 346             // Load the tabs according to the theme.
 347             if (MainWebViewActivity.darkTheme) {  // The dark theme is applied.
 348                 // Set the background color.  We have to use the deprecated `.getColor()` until API >= 23.
 349                 //noinspection deprecation
 350                 tabWebView.setBackgroundColor(getResources().getColor(R.color.gray_850));
 351
 352                 switch (tabNumber) {
 353                     case 1:
 354                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_permissions_dark.html");
 355                         break;
 356
 357                     case 2:
 358                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_privacy_policy_dark.html");
 359                         break;
 360
 361                     case 3:
 362                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_changelog_dark.html");
 363                         break;
 364
 365                     case 4:
 366                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_licenses_dark.html");
 367                         break;
 368
 369                     case 5:
 370                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_contributors_dark.html");
 371                         break;
 372
 373                     case 6:
 374                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_links_dark.html");
 375                         break;
 376                 }
 377             } else {  // The light theme is applied.
 378                 switch (tabNumber) {
 379                     case 1:
 380                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_permissions_light.html");
 381                         break;
 382
 383                     case 2:
 384                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_privacy_policy_light.html");
 385                         break;
 386
 387                     case 3:
 388                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_changelog_light.html");
 389                         break;
 390
 391                     case 4:
 392                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_licenses_light.html");
 393                         break;
 394
 395                     case 5:
 396                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_contributors_light.html");
 397                         break;
 398
 399                     case 6:
 400                         tabWebView.loadUrl("file:///android_asset/" + getString(R.string.android_asset_path) + "/about_links_light.html");
 401                         break;
 402                 }
 403             }
 404         }
 405
 406         // Return the formatted `tabLayout`.
 407         return tabLayout;
 408     }
 409 }