Cache paging data using the cachedIn() extension

app/build.gradle

@@ -293,7 +293,7 @@ dependencies {
     implementation 'androidx.compose.material3:material3'
     implementation 'androidx.activity:activity-compose'
     implementation 'androidx.compose.ui:ui-tooling-preview'
-    implementation 'androidx.compose.ui:ui-text:1.7.0-beta03' // Needed for parsing HTML to AnnotatedString
+    implementation 'androidx.compose.ui:ui-text:1.7.0-beta04' // Needed for parsing HTML to AnnotatedString
     implementation 'com.github.nanihadesuka:LazyColumnScrollbar:2.1.0'
 
     // Paging

app/src/main/java/org/schabi/newpipe/compose/comment/Comment.kt

@@ -20,6 +20,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
@@ -37,6 +38,7 @@ import androidx.compose.ui.unit.dp
 import androidx.fragment.app.FragmentActivity
 import androidx.paging.Pager
 import androidx.paging.PagingConfig
+import androidx.paging.cachedIn
 import coil.compose.AsyncImage
 import org.schabi.newpipe.R
 import org.schabi.newpipe.compose.theme.AppTheme
@@ -141,13 +143,15 @@ fun Comment(comment: CommentsInfoItem) {
 
     if (showReplies) {
         ModalBottomSheet(onDismissRequest = { showReplies = false }) {
-            val flow = remember(comment) {
+            val coroutineScope = rememberCoroutineScope()
+            val flow = remember(coroutineScope) {
                 Pager(PagingConfig(pageSize = 20, enablePlaceholders = false)) {
                     CommentsSource(comment.serviceId, comment.url, comment.replies)
                 }.flow
+                    .cachedIn(coroutineScope)
             }
 
-            CommentSection(parentComment = comment, flow = flow)
+            CommentSection(parentComment = comment, commentsData = flow)
         }
     }
 }

app/src/main/java/org/schabi/newpipe/compose/comment/CommentSection.kt

@@ -36,13 +36,13 @@ import org.schabi.newpipe.paging.CommentsDisabledException
 @Composable
 fun CommentSection(
     parentComment: CommentsInfoItem? = null,
-    flow: Flow<PagingData<CommentsInfoItem>>
+    commentsData: Flow<PagingData<CommentsInfoItem>>
 ) {
-    val replies = flow.collectAsLazyPagingItems()
-    val itemCount by remember { derivedStateOf { replies.itemCount } }
+    val comments = commentsData.collectAsLazyPagingItems()
+    val itemCount by remember { derivedStateOf { comments.itemCount } }
 
     Surface(color = MaterialTheme.colorScheme.background) {
-        val refresh = replies.loadState.refresh
+        val refresh = comments.loadState.refresh
         if (itemCount == 0 && refresh !is LoadState.Loading) {
             NoCommentsMessage((refresh as? LoadState.Error)?.error)
         } else {
@@ -58,7 +58,7 @@ fun CommentSection(
                     }
 
                     items(itemCount) {
-                        Comment(comment = replies[it]!!)
+                        Comment(comment = comments[it]!!)
                     }
                 }
             }
@@ -113,7 +113,7 @@ private fun CommentSectionPreview(
     @PreviewParameter(CommentDataProvider::class) pagingData: PagingData<CommentsInfoItem>
 ) {
     AppTheme {
-        CommentSection(flow = flowOf(pagingData))
+        CommentSection(commentsData = flowOf(pagingData))
     }
 }
 
@@ -137,6 +137,6 @@ private fun CommentRepliesPreview() {
     val flow = flowOf(PagingData.from(replies))
 
     AppTheme {
-        CommentSection(parentComment = comment, flow = flow)
+        CommentSection(parentComment = comment, commentsData = flow)
     }
 }

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

@@ -5,12 +5,14 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.ui.platform.ComposeView
 import androidx.compose.ui.platform.ViewCompositionStrategy
 import androidx.core.os.bundleOf
 import androidx.fragment.app.Fragment
 import androidx.paging.Pager
 import androidx.paging.PagingConfig
+import androidx.paging.cachedIn
 import org.schabi.newpipe.compose.comment.CommentSection
 import org.schabi.newpipe.compose.theme.AppTheme
 import org.schabi.newpipe.paging.CommentsSource
@@ -29,14 +31,16 @@ class CommentsFragment : Fragment() {
         return ComposeView(requireContext()).apply {
             setViewCompositionStrategy(ViewCompositionStrategy.DisposeOnViewTreeLifecycleDestroyed)
             setContent {
-                val flow = remember(serviceId, url) {
+                val coroutineScope = rememberCoroutineScope()
+                val flow = remember(coroutineScope) {
                     Pager(PagingConfig(pageSize = 20, enablePlaceholders = false)) {
                         CommentsSource(serviceId, url, null)
                     }.flow
+                        .cachedIn(coroutineScope)
                 }
 
                 AppTheme {
-                    CommentSection(flow = flow)
+                    CommentSection(commentsData = flow)
                 }
             }
         }

app/src/main/java/org/schabi/newpipe/paging/CommentsSource.kt

@@ -1,35 +1,42 @@
 package org.schabi.newpipe.paging
 
+import androidx.paging.PagingSource
 import androidx.paging.PagingState
-import androidx.paging.rxjava3.RxPagingSource
-import io.reactivex.rxjava3.core.Single
-import io.reactivex.rxjava3.schedulers.Schedulers
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import org.schabi.newpipe.extractor.NewPipe
 import org.schabi.newpipe.extractor.Page
+import org.schabi.newpipe.extractor.comments.CommentsInfo
 import org.schabi.newpipe.extractor.comments.CommentsInfoItem
-import org.schabi.newpipe.util.ExtractorHelper
+import org.schabi.newpipe.util.NO_SERVICE_ID
 
 class CommentsSource(
-    private val serviceId: Int,
+    serviceId: Int,
     private val url: String?,
     private val repliesPage: Page?
-) : RxPagingSource<Page, CommentsInfoItem>() {
-    override fun loadSingle(params: LoadParams<Page>): Single<LoadResult<Page, CommentsInfoItem>> {
+) : PagingSource<Page, CommentsInfoItem>() {
+    init {
+        require(serviceId != NO_SERVICE_ID) { "serviceId is NO_SERVICE_ID" }
+    }
+    private val service = NewPipe.getService(serviceId)
+
+    override suspend fun load(params: LoadParams<Page>): LoadResult<Page, CommentsInfoItem> {
         // repliesPage is non-null only when used to load the comment replies
         val nextKey = params.key ?: repliesPage
 
-        return nextKey?.let {
-            ExtractorHelper.getMoreCommentItems(serviceId, url, it)
-                .subscribeOn(Schedulers.io())
-                .map { LoadResult.Page(it.items, null, it.nextPage) }
-        } ?: ExtractorHelper.getCommentsInfo(serviceId, url, false)
-            .subscribeOn(Schedulers.io())
-            .map {
-                if (it.isCommentsDisabled) {
+        return withContext(Dispatchers.IO) {
+            nextKey?.let {
+                val info = CommentsInfo.getMoreItems(service, url, it)
+                LoadResult.Page(info.items, null, info.nextPage)
+            } ?: run {
+                val info = CommentsInfo.getInfo(service, url)
+                if (info.isCommentsDisabled) {
                     LoadResult.Error(CommentsDisabledException())
                 } else {
-                    LoadResult.Page(it.relatedItems, null, it.nextPage)
+                    LoadResult.Page(info.relatedItems, null, info.nextPage)
                 }
             }
+        }
     }
 
     override fun getRefreshKey(state: PagingState<Page, CommentsInfoItem>) = null

app/src/main/java/org/schabi/newpipe/util/ExtractorHelper.java

@@ -42,8 +42,6 @@ import org.schabi.newpipe.extractor.NewPipe;
 import org.schabi.newpipe.extractor.Page;
 import org.schabi.newpipe.extractor.channel.ChannelInfo;
 import org.schabi.newpipe.extractor.channel.tabs.ChannelTabInfo;
-import org.schabi.newpipe.extractor.comments.CommentsInfo;
-import org.schabi.newpipe.extractor.comments.CommentsInfoItem;
 import org.schabi.newpipe.extractor.kiosk.KioskInfo;
 import org.schabi.newpipe.extractor.linkhandler.ListLinkHandler;
 import org.schabi.newpipe.extractor.playlist.PlaylistInfo;
@@ -146,24 +144,6 @@ public final class ExtractorHelper {
                         listLinkHandler, nextPage));
     }
 
-    public static Single<CommentsInfo> getCommentsInfo(final int serviceId,
-                                                       final String url,
-                                                       final boolean forceLoad) {
-        checkServiceId(serviceId);
-        return checkCache(forceLoad, serviceId, url, InfoCache.Type.COMMENTS,
-                Single.fromCallable(() ->
-                        CommentsInfo.getInfo(NewPipe.getService(serviceId), url)));
-    }
-
-    public static Single<InfoItemsPage<CommentsInfoItem>> getMoreCommentItems(
-            final int serviceId,
-            final String url,
-            final Page nextPage) {
-        checkServiceId(serviceId);
-        return Single.fromCallable(() ->
-                CommentsInfo.getMoreItems(NewPipe.getService(serviceId), url, nextPage));
-    }
-
     public static Single<PlaylistInfo> getPlaylistInfo(final int serviceId,
                                                        final String url,
                                                        final boolean forceLoad) {