Various code improvements

app/src/main/java/androidx/fragment/app/FragmentStatePagerAdapterMenuWorkaround.java

@@ -86,8 +86,8 @@ public abstract class FragmentStatePagerAdapterMenuWorkaround extends PagerAdapt
     private final int mBehavior;
     private FragmentTransaction mCurTransaction = null;
 
-    private ArrayList<Fragment.SavedState> mSavedState = new ArrayList<Fragment.SavedState>();
-    private ArrayList<Fragment> mFragments = new ArrayList<Fragment>();
+    private final ArrayList<Fragment.SavedState> mSavedState = new ArrayList<Fragment.SavedState>();
+    private final ArrayList<Fragment> mFragments = new ArrayList<Fragment>();
     private Fragment mCurrentPrimaryItem = null;
 
     /**

app/src/main/java/org/schabi/newpipe/DownloaderImpl.java

@@ -50,8 +50,8 @@ public final class DownloaderImpl extends Downloader {
     public static final String YOUTUBE_DOMAIN = "youtube.com";
 
     private static DownloaderImpl instance;
-    private Map<String, String> mCookies;
-    private OkHttpClient client;
+    private final Map<String, String> mCookies;
+    private final OkHttpClient client;
 
     private DownloaderImpl(final OkHttpClient.Builder builder) {
         if (Build.VERSION.SDK_INT == Build.VERSION_CODES.KITKAT) {

app/src/main/java/org/schabi/newpipe/MainActivity.java

@@ -139,8 +139,7 @@ protected void onCreate(final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
-        if (getSupportFragmentManager() != null
-                && getSupportFragmentManager().getBackStackEntryCount() == 0) {
+        if (getSupportFragmentManager().getBackStackEntryCount() == 0) {
             initFragments();
         }
 

app/src/main/java/org/schabi/newpipe/RouterActivity.java

@@ -519,7 +519,7 @@ private void openDownloadDialog() {
         disposables.add(ExtractorHelper.getStreamInfo(currentServiceId, currentUrl, true)
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
-                .subscribe((@NonNull StreamInfo result) -> {
+                .subscribe(result -> {
                     final List<VideoStream> sortedVideoStreams = ListHelper
                             .getSortedStreamVideosList(this, result.getVideoStreams(),
                                     result.getVideoOnlyStreams(), false);
@@ -534,9 +534,8 @@ private void openDownloadDialog() {
                     downloadDialog.show(fm, "downloadDialog");
                     fm.executePendingTransactions();
                     downloadDialog.requireDialog().setOnDismissListener(dialog -> finish());
-                }, (@NonNull Throwable throwable) -> {
-                    showUnsupportedUrlDialog(currentUrl);
-                }));
+                }, throwable ->
+                        showUnsupportedUrlDialog(currentUrl)));
     }
 
     @Override

app/src/main/java/org/schabi/newpipe/about/AboutActivity.java

@@ -31,7 +31,7 @@ public class AboutActivity extends AppCompatActivity {
     /**
      * List of all software components.
      */
-    private static final SoftwareComponent[] SOFTWARE_COMPONENTS = new SoftwareComponent[]{
+    private static final SoftwareComponent[] SOFTWARE_COMPONENTS = {
             new SoftwareComponent("Giga Get", "2014 - 2015", "Peter Cai",
                     "https://github.com/PaperAirplane-Dev-Team/GigaGet", StandardLicenses.GPL3),
             new SoftwareComponent("NewPipe Extractor", "2017 - 2020", "Christian Schabesberger",

app/src/main/java/org/schabi/newpipe/about/License.java

@@ -23,7 +23,7 @@ public License[] newArray(final int size) {
     };
     private final String abbreviation;
     private final String name;
-    private String filename;
+    private final String filename;
 
     public License(final String name, final String abbreviation, final String filename) {
         if (name == null) {

app/src/main/java/org/schabi/newpipe/fragments/MainFragment.java

@@ -43,7 +43,7 @@ public class MainFragment extends BaseFragment implements TabLayout.OnTabSelecte
     private SelectedTabsPagerAdapter pagerAdapter;
     private ScrollableTabLayout tabLayout;
 
-    private List<Tab> tabsList = new ArrayList<>();
+    private final List<Tab> tabsList = new ArrayList<>();
     private TabsManager tabsManager;
 
     private boolean hasTabsChanged = false;

app/src/main/java/org/schabi/newpipe/fragments/OnScrollBelowItemsListener.java

@@ -14,12 +14,10 @@ public void onScrolled(final RecyclerView recyclerView, final int dx, final int
         super.onScrolled(recyclerView, dx, dy);
         if (dy > 0) {
             int pastVisibleItems = 0;
-            final int visibleItemCount;
-            final int totalItemCount;
             final RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
 
-            visibleItemCount = layoutManager.getChildCount();
-            totalItemCount = layoutManager.getItemCount();
+            final int visibleItemCount = layoutManager.getChildCount();
+            final int totalItemCount = layoutManager.getItemCount();
 
             // Already covers the GridLayoutManager case
             if (layoutManager instanceof LinearLayoutManager) {

app/src/main/java/org/schabi/newpipe/fragments/detail/VideoDetailFragment.java

@@ -19,7 +19,6 @@
 import androidx.core.text.HtmlCompat;
 import androidx.preference.PreferenceManager;
 import android.provider.Settings;
-import android.text.Spanned;
 import android.text.TextUtils;
 import android.text.util.Linkify;
 import android.util.DisplayMetrics;
@@ -731,7 +730,7 @@ protected void initListeners() {
     }
 
     private View.OnTouchListener getOnControlsTouchListener() {
-        return (View view, MotionEvent motionEvent) -> {
+        return (view, motionEvent) -> {
             if (!PreferenceManager.getDefaultSharedPreferences(activity)
                     .getBoolean(getString(R.string.show_hold_to_append_key), true)) {
                 return false;
@@ -948,7 +947,7 @@ private void runWorker(final boolean forceLoad, final boolean addToBackStack) {
         currentWorker = ExtractorHelper.getStreamInfo(serviceId, url, forceLoad)
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
-                .subscribe((@NonNull final StreamInfo result) -> {
+                .subscribe(result -> {
                     isLoading.set(false);
                     hideMainPlayer();
                     if (result.getAgeLimit() != NO_AGE_LIMIT && !prefs.getBoolean(
@@ -969,7 +968,7 @@ private void runWorker(final boolean forceLoad, final boolean addToBackStack) {
                             openVideoPlayer();
                         }
                     }
-                }, (@NonNull final Throwable throwable) -> {
+                }, throwable -> {
                     isLoading.set(false);
                     onError(throwable);
                 });
@@ -1140,7 +1139,7 @@ private PlayQueue setupPlayQueueForIntent(final boolean append) {
 
         PlayQueue queue = playQueue;
         // Size can be 0 because queue removes bad stream automatically when error occurs
-        if (queue == null || queue.size() == 0) {
+        if (queue == null || queue.isEmpty()) {
             queue = new SinglePlayQueue(currentInfo);
         }
 
@@ -1224,12 +1223,12 @@ private void prepareDescription(final Description description) {
 
         if (description.getType() == Description.HTML) {
             disposables.add(Single.just(description.getContent())
-                    .map((@NonNull final String descriptionText) ->
+                    .map(descriptionText ->
                             HtmlCompat.fromHtml(descriptionText,
                                     HtmlCompat.FROM_HTML_MODE_LEGACY))
                     .subscribeOn(Schedulers.computation())
                     .observeOn(AndroidSchedulers.mainThread())
-                    .subscribe((@NonNull final Spanned spanned) -> {
+                    .subscribe(spanned -> {
                         videoDescriptionView.setText(spanned);
                         videoDescriptionView.setVisibility(View.VISIBLE);
                     }));
@@ -1346,19 +1345,24 @@ private void setupBroadcastReceiver() {
         broadcastReceiver = new BroadcastReceiver() {
             @Override
             public void onReceive(final Context context, final Intent intent) {
-                if (intent.getAction().equals(ACTION_SHOW_MAIN_PLAYER)) {
-                    bottomSheetBehavior.setState(BottomSheetBehavior.STATE_EXPANDED);
-                } else if (intent.getAction().equals(ACTION_HIDE_MAIN_PLAYER)) {
-                    bottomSheetBehavior.setState(BottomSheetBehavior.STATE_HIDDEN);
-                } else if (intent.getAction().equals(ACTION_PLAYER_STARTED)) {
-                    // If the state is not hidden we don't need to show the mini player
-                    if (bottomSheetBehavior.getState() == BottomSheetBehavior.STATE_HIDDEN) {
-                        bottomSheetBehavior.setState(BottomSheetBehavior.STATE_COLLAPSED);
-                    }
-                    // Rebound to the service if it was closed via notification or mini player
-                    if (!PlayerHolder.bound) {
-                        PlayerHolder.startService(App.getApp(), false, VideoDetailFragment.this);
-                    }
+                switch (intent.getAction()) {
+                    case ACTION_SHOW_MAIN_PLAYER:
+                        bottomSheetBehavior.setState(BottomSheetBehavior.STATE_EXPANDED);
+                        break;
+                    case ACTION_HIDE_MAIN_PLAYER:
+                        bottomSheetBehavior.setState(BottomSheetBehavior.STATE_HIDDEN);
+                        break;
+                    case ACTION_PLAYER_STARTED:
+                        // If the state is not hidden we don't need to show the mini player
+                        if (bottomSheetBehavior.getState() == BottomSheetBehavior.STATE_HIDDEN) {
+                            bottomSheetBehavior.setState(BottomSheetBehavior.STATE_COLLAPSED);
+                        }
+                        // Rebound to the service if it was closed via notification or mini player
+                        if (!PlayerHolder.bound) {
+                            PlayerHolder.startService(
+                                    App.getApp(), false, VideoDetailFragment.this);
+                        }
+                        break;
                 }
             }
         };

app/src/main/java/org/schabi/newpipe/fragments/list/BaseListInfoFragment.java

@@ -204,7 +204,7 @@ public void handleResult(@NonNull final I result) {
         name = result.getName();
         setTitle(name);
 
-        if (infoListAdapter.getItemsList().size() == 0) {
+        if (infoListAdapter.getItemsList().isEmpty()) {
             if (result.getRelatedItems().size() > 0) {
                 infoListAdapter.addInfoItemList(result.getRelatedItems());
                 showListFooter(hasMoreItems());

app/src/main/java/org/schabi/newpipe/fragments/list/comments/CommentsFragment.java

@@ -24,7 +24,7 @@
 import io.reactivex.disposables.CompositeDisposable;
 
 public class CommentsFragment extends BaseListInfoFragment<CommentsInfo> {
-    private CompositeDisposable disposables = new CompositeDisposable();
+    private final CompositeDisposable disposables = new CompositeDisposable();
 
     public static CommentsFragment getInstance(final int serviceId, final  String url,
                                                final String name) {

app/src/main/java/org/schabi/newpipe/fragments/list/search/SearchFragment.java

@@ -256,7 +256,7 @@ public void onResume() {
         if (!TextUtils.isEmpty(searchString)) {
             if (wasLoading.getAndSet(false)) {
                 search(searchString, contentFilter, sortFilter);
-            } else if (infoListAdapter.getItemsList().size() == 0) {
+            } else if (infoListAdapter.getItemsList().isEmpty()) {
                 if (savedState == null) {
                     search(searchString, contentFilter, sortFilter);
                 } else if (!isLoading.get() && !wasSearchFocused) {
@@ -977,7 +977,7 @@ public void handleResult(@NonNull final SearchInfo result) {
         lastSearchedString = searchString;
         nextPage = result.getNextPage();
 
-        if (infoListAdapter.getItemsList().size() == 0) {
+        if (infoListAdapter.getItemsList().isEmpty()) {
             if (!result.getRelatedItems().isEmpty()) {
                 infoListAdapter.addInfoItemList(result.getRelatedItems());
             } else {

app/src/main/java/org/schabi/newpipe/fragments/list/videos/RelatedVideosFragment.java

@@ -31,7 +31,7 @@
 public class RelatedVideosFragment extends BaseListInfoFragment<RelatedStreamInfo>
         implements SharedPreferences.OnSharedPreferenceChangeListener {
     private static final String INFO_KEY = "related_info_key";
-    private CompositeDisposable disposables = new CompositeDisposable();
+    private final CompositeDisposable disposables = new CompositeDisposable();
     private RelatedStreamInfo relatedStreamInfo;
 
     /*//////////////////////////////////////////////////////////////////////////

app/src/main/java/org/schabi/newpipe/info_list/InfoListAdapter.java

@@ -371,7 +371,7 @@ public int getSpanSize(final int position) {
         };
     }
 
-    public class HFHolder extends RecyclerView.ViewHolder {
+    public static class HFHolder extends RecyclerView.ViewHolder {
         public View view;
 
         HFHolder(final View v) {

app/src/main/java/org/schabi/newpipe/local/dialog/PlaylistAppendDialog.java

@@ -38,7 +38,7 @@ public final class PlaylistAppendDialog extends PlaylistDialog {
     private RecyclerView playlistRecyclerView;
     private LocalItemListAdapter playlistAdapter;
 
-    private CompositeDisposable playlistDisposables = new CompositeDisposable();
+    private final CompositeDisposable playlistDisposables = new CompositeDisposable();
 
     public static Disposable onPlaylistFound(
             final Context context, final Runnable onSuccess, final Runnable onFailed

app/src/main/java/org/schabi/newpipe/local/feed/FeedFragment.kt

@@ -29,6 +29,7 @@ import android.view.MenuItem
 import android.view.View
 import android.view.ViewGroup
 import androidx.appcompat.app.AlertDialog
+import androidx.core.content.edit
 import androidx.core.os.bundleOf
 import androidx.core.view.isVisible
 import androidx.lifecycle.Observer
@@ -142,9 +143,9 @@ class FeedFragment : BaseListFragment<FeedState, Unit>() {
             AlertDialog.Builder(requireContext())
                     .setMessage(R.string.feed_use_dedicated_fetch_method_help_text)
                     .setNeutralButton(enableDisableButtonText) { _, _ ->
-                        sharedPreferences.edit()
-                                .putBoolean(getString(R.string.feed_use_dedicated_fetch_method_key), !usingDedicatedMethod)
-                                .apply()
+                        sharedPreferences.edit {
+                            putBoolean(getString(R.string.feed_use_dedicated_fetch_method_key), !usingDedicatedMethod)
+                        }
                     }
                     .setPositiveButton(resources.getString(R.string.finish), null)
                     .create()
@@ -255,8 +256,9 @@ class FeedFragment : BaseListFragment<FeedState, Unit>() {
 
         oldestSubscriptionUpdate = loadedState.oldestUpdate
 
-        refresh_subtitle_text.isVisible = loadedState.notLoadedCount > 0
-        if (loadedState.notLoadedCount > 0) {
+        val loadedCount = loadedState.notLoadedCount > 0
+        refresh_subtitle_text.isVisible = loadedCount
+        if (loadedCount) {
             refresh_subtitle_text.text = getString(R.string.feed_subscription_not_loaded_count, loadedState.notLoadedCount)
         }
 

app/src/main/java/org/schabi/newpipe/local/feed/FeedViewModel.kt

@@ -48,8 +48,7 @@ class FeedViewModel(applicationContext: Context, val groupId: Long = FeedGroupEn
             .throttleLatest(DEFAULT_THROTTLE_TIMEOUT, TimeUnit.MILLISECONDS)
             .subscribeOn(Schedulers.io())
             .observeOn(AndroidSchedulers.mainThread())
-            .subscribe {
-                val (event, listFromDB, notLoadedCount, oldestUpdate) = it
+            .subscribe { (event, listFromDB, notLoadedCount, oldestUpdate) ->
 
                 val oldestUpdateCalendar = oldestUpdate?.toCalendar()
 

app/src/main/java/org/schabi/newpipe/local/subscription/dialog/FeedGroupDialog.kt

@@ -3,7 +3,6 @@ package org.schabi.newpipe.local.subscription.dialog
 import android.app.Dialog
 import android.os.Bundle
 import android.os.Parcelable
-import android.text.TextUtils
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -225,7 +224,7 @@ class FeedGroupDialog : DialogFragment(), BackPressable {
         }
 
         toolbar_search_clear.setOnClickListener {
-            if (TextUtils.isEmpty(toolbar_search_edit_text.text)) {
+            if (toolbar_search_edit_text.text.isEmpty()) {
                 hideSearch()
                 return@setOnClickListener
             }

app/src/main/java/org/schabi/newpipe/player/BasePlayer.java

@@ -1545,8 +1545,7 @@ public PlaybackParameters getPlaybackParameters() {
         if (simpleExoPlayer == null) {
             return PlaybackParameters.DEFAULT;
         }
-        final PlaybackParameters parameters = simpleExoPlayer.getPlaybackParameters();
-        return parameters == null ? PlaybackParameters.DEFAULT : parameters;
+        return simpleExoPlayer.getPlaybackParameters();
     }
 
     /**

app/src/main/java/org/schabi/newpipe/player/NotificationUtil.java

@@ -48,7 +48,7 @@ public final class NotificationUtil {
     @Nullable private static NotificationUtil instance = null;
 
     @NotificationConstants.Action
-    private int[] notificationSlots = NotificationConstants.SLOT_DEFAULTS.clone();
+    private final int[] notificationSlots = NotificationConstants.SLOT_DEFAULTS.clone();
 
     private NotificationManagerCompat notificationManager;
     private NotificationCompat.Builder notificationBuilder;

app/src/main/java/org/schabi/newpipe/player/VideoPlayerImpl.java

@@ -337,7 +337,7 @@ protected void setupSubtitleView(final @NonNull SubtitleView view,
             view.setFixedTextSize(TypedValue.COMPLEX_UNIT_PX,
                     (float) minimumLength / captionRatioInverse);
         }
-        view.setApplyEmbeddedStyles(captionStyle.equals(CaptionStyleCompat.DEFAULT));
+        view.setApplyEmbeddedStyles(captionStyle == CaptionStyleCompat.DEFAULT);
         view.setStyle(captionStyle);
     }
 

app/src/main/java/org/schabi/newpipe/player/event/BasePlayerGestureListener.kt

@@ -15,6 +15,7 @@ import org.schabi.newpipe.util.AnimationUtils
 import kotlin.math.abs
 import kotlin.math.hypot
 import kotlin.math.max
+import kotlin.math.min
 
 /**
  * Base gesture handling for [VideoPlayerImpl]
@@ -117,7 +118,7 @@ abstract class BasePlayerGestureListener(
             initSecPointerX = event.getX(1)
             initSecPointerY = event.getY(1)
             // record distance between fingers
-            initPointerDistance = Math.hypot(initFirstPointerX - initSecPointerX.toDouble(),
+            initPointerDistance = hypot(initFirstPointerX - initSecPointerX.toDouble(),
                 initFirstPointerY - initSecPointerY.toDouble())
 
             isResizing = true
@@ -185,7 +186,7 @@ abstract class BasePlayerGestureListener(
                 playerImpl.updateScreenSize()
 
                 playerImpl.updatePopupSize(
-                    Math.min(playerImpl.screenWidth.toDouble(), newWidth).toInt(),
+                    min(playerImpl.screenWidth.toDouble(), newWidth).toInt(),
                     -1)
                 return true
             }

app/src/main/java/org/schabi/newpipe/player/playback/MediaSourceManager.java

@@ -123,7 +123,7 @@ public class MediaSourceManager {
     @NonNull
     private ManagedMediaSourcePlaylist playlist;
 
-    private Handler removeMediaSourceHandler = new Handler();
+    private final Handler removeMediaSourceHandler = new Handler();
 
     public MediaSourceManager(@NonNull final PlaybackListener listener,
                               @NonNull final PlayQueue playQueue) {

app/src/main/java/org/schabi/newpipe/player/playqueue/PlayQueueAdapter.java

@@ -215,7 +215,7 @@ public void onBindViewHolder(final RecyclerView.ViewHolder holder, final int pos
         }
     }
 
-    public class HFHolder extends RecyclerView.ViewHolder {
+    public static class HFHolder extends RecyclerView.ViewHolder {
         public View view;
 
         public HFHolder(final View v) {