Add a few comments and rename a few methods

app/src/main/java/org/schabi/newpipe/fragments/list/channel/ChannelFragment.java

@@ -259,7 +259,7 @@ public class ChannelFragment extends BaseListInfoFragment<ChannelInfo>
                 .map(List::isEmpty)
                 .distinctUntilChanged()
                 .skip(1) // channel has just been opened
-                .filter(x -> NotificationHelper.isNewStreamsNotificationsEnabled(requireContext()))
+                .filter(x -> NotificationHelper.areNewStreamsNotificationsEnabled(requireContext()))
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(isEmpty -> {
                     if (!isEmpty) {
@@ -402,7 +402,7 @@ public class ChannelFragment extends BaseListInfoFragment<ChannelInfo>
         }
         if (subscription != null) {
             menuNotifyButton.setEnabled(
-                    NotificationHelper.isNewStreamsNotificationsEnabled(requireContext())
+                    NotificationHelper.areNewStreamsNotificationsEnabled(requireContext())
             );
             menuNotifyButton.setChecked(
                     subscription.getNotificationMode() == NotificationMode.ENABLED
@@ -423,6 +423,9 @@ public class ChannelFragment extends BaseListInfoFragment<ChannelInfo>
         );
     }
 
+    /**
+     * Show a snackbar with the option to enable notifications on new streams for this channel.
+     */
     private void showNotifySnackbar() {
         Snackbar.make(itemsList, R.string.you_successfully_subscribed, Snackbar.LENGTH_LONG)
                 .setAction(R.string.get_notified, v -> setNotify(true))

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

@@ -21,13 +21,20 @@ import org.schabi.newpipe.extractor.stream.StreamInfoItem
 import org.schabi.newpipe.local.feed.service.FeedUpdateInfo
 import org.schabi.newpipe.util.NavigationHelper
 
+/**
+ * Helper for everything related to show notifications about new streams to the user.
+ */
 class NotificationHelper(val context: Context) {
 
     private val manager = context.getSystemService(
         Context.NOTIFICATION_SERVICE
     ) as NotificationManager
 
-    fun notify(data: FeedUpdateInfo): Completable {
+    /**
+     * Show a notification about new streams from a single channel.
+     * Opening the notification will open the corresponding channel page.
+     */
+    fun displayNewStreamsNotification(data: FeedUpdateInfo): Completable {
         val newStreams: List<StreamInfoItem> = data.newStreams
         val summary = context.resources.getQuantityString(
             R.plurals.new_streams, newStreams.size, newStreams.size
@@ -69,11 +76,14 @@ class NotificationHelper(val context: Context) {
         style.setSummaryText(summary)
         style.setBigContentTitle(data.name)
         builder.setStyle(style)
+        // open the channel page when clicking on the notification
         builder.setContentIntent(
             PendingIntent.getActivity(
                 context,
                 data.pseudoId,
-                NavigationHelper.getChannelIntent(context, data.listInfo.serviceId, data.listInfo.url)
+                NavigationHelper.getChannelIntent(
+                    context, data.listInfo.serviceId, data.listInfo.url
+                )
                     .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK),
                 0
             )
@@ -110,7 +120,7 @@ class NotificationHelper(val context: Context) {
         }
 
         @JvmStatic
-        fun isNewStreamsNotificationsEnabled(context: Context): Boolean {
+        fun areNewStreamsNotificationsEnabled(context: Context): Boolean {
             return (
                 PreferenceManager.getDefaultSharedPreferences(context)
                     .getBoolean(context.getString(R.string.enable_streams_notifications), false) &&

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

@@ -21,6 +21,10 @@ import org.schabi.newpipe.local.feed.service.FeedLoadManager
 import org.schabi.newpipe.local.feed.service.FeedLoadService
 import java.util.concurrent.TimeUnit
 
+/*
+ * Worker which checks for new streams of subscribed channels
+ * in intervals which can be set by the user in the settings.
+ */
 class NotificationWorker(
     appContext: Context,
     workerParams: WorkerParameters,
@@ -43,7 +47,7 @@ class NotificationWorker(
             }
             .doOnSubscribe { setForegroundAsync(createForegroundInfo()) }
             .flatMapObservable { Observable.fromIterable(it) }
-            .flatMapCompletable { x -> notificationHelper.notify(x) }
+            .flatMapCompletable { x -> notificationHelper.displayNewStreamsNotification(x) }
             .toSingleDefault(Result.success())
             .onErrorReturnItem(Result.failure())
     } else Single.just(Result.success())

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

@@ -5,6 +5,10 @@ import androidx.preference.PreferenceManager
 import org.schabi.newpipe.R
 import java.util.concurrent.TimeUnit
 
+/**
+ * Information for the Scheduler which checks for new streams.
+ * See [NotificationWorker]
+ */
 data class ScheduleOptions(
     val interval: Long,
     val isRequireNonMeteredNetwork: Boolean