Fix BrowseSourceScreen list/grid unnecessary reloads (#8661)

app/src/main/java/eu/kanade/tachiyomi/ui/browse/migration/search/SourceSearchScreen.kt

@@ -76,15 +76,13 @@ data class SourceSearchScreen(
             },
             snackbarHost = { SnackbarHost(hostState = snackbarHostState) },
         ) { paddingValues ->
-            val mangaList = remember(state.currentFilter) {
-                screenModel.getMangaListFlow(state.currentFilter)
-            }.collectAsLazyPagingItems()
+            val pagingFlow by screenModel.mangaPagerFlowFlow.collectAsState()
             val openMigrateDialog: (Manga) -> Unit = {
                 screenModel.setDialog(BrowseSourceScreenModel.Dialog.Migrate(it))
             }
             BrowseSourceContent(
                 source = screenModel.source,
-                mangaList = mangaList,
+                mangaList = pagingFlow.collectAsLazyPagingItems(),
                 columns = screenModel.getColumnsPreference(LocalConfiguration.current.orientation),
                 displayMode = screenModel.displayMode,
                 snackbarHostState = snackbarHostState,

app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreen.kt

@@ -173,13 +173,11 @@ data class BrowseSourceScreen(
             },
             snackbarHost = { SnackbarHost(hostState = snackbarHostState) },
         ) { paddingValues ->
-            val mangaList = remember(state.currentFilter) {
-                screenModel.getMangaListFlow(state.currentFilter)
-            }.collectAsLazyPagingItems()
+            val pagingFlow by screenModel.mangaPagerFlowFlow.collectAsState()
 
             BrowseSourceContent(
                 source = screenModel.source,
-                mangaList = mangaList,
+                mangaList = pagingFlow.collectAsLazyPagingItems(),
                 columns = screenModel.getColumnsPreference(LocalConfiguration.current.orientation),
                 displayMode = screenModel.displayMode,
                 snackbarHostState = snackbarHostState,

app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceScreenModel.kt

@@ -9,7 +9,6 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.unit.dp
 import androidx.paging.Pager
 import androidx.paging.PagingConfig
-import androidx.paging.PagingData
 import androidx.paging.cachedIn
 import androidx.paging.map
 import cafe.adriel.voyager.core.model.StateScreenModel
@@ -64,8 +63,9 @@ import eu.kanade.tachiyomi.util.lang.withIOContext
 import eu.kanade.tachiyomi.util.lang.withNonCancellableContext
 import eu.kanade.tachiyomi.util.removeCovers
 import eu.kanade.tachiyomi.util.system.logcat
-import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.emptyFlow
 import kotlinx.coroutines.flow.filterNotNull
 import kotlinx.coroutines.flow.firstOrNull
 import kotlinx.coroutines.flow.map
@@ -114,6 +114,30 @@ class BrowseSourceScreenModel(
      */
     private var filterSheet: SourceFilterSheet? = null
 
+    /**
+     * Flow of Pager flow tied to [State.currentFilter]
+     */
+    val mangaPagerFlowFlow = state.map { it.currentFilter }
+        .distinctUntilChanged()
+        .map { currentFilter ->
+            Pager(
+                PagingConfig(pageSize = 25),
+            ) {
+                getRemoteManga.subscribe(sourceId, currentFilter.query ?: "", currentFilter.filters)
+            }.flow
+                .map { pagingData ->
+                    pagingData.map { sManga ->
+                        val dbManga = withIOContext { networkToLocalManga.await(sManga.toDomainManga(sourceId)) }
+                        getManga.subscribe(dbManga.url, dbManga.source)
+                            .filterNotNull()
+                            .onEach { initializeManga(it) }
+                            .stateIn(coroutineScope)
+                    }
+                }
+                .cachedIn(coroutineScope)
+        }
+        .stateIn(coroutineScope, SharingStarted.Lazily, emptyFlow())
+
     init {
         mutableState.update { it.copy(filters = source.getFilterList()) }
     }
@@ -128,24 +152,6 @@ class BrowseSourceScreenModel(
         return if (columns == 0) GridCells.Adaptive(128.dp) else GridCells.Fixed(columns)
     }
 
-    fun getMangaListFlow(currentFilter: Filter): Flow<PagingData<StateFlow<Manga>>> {
-        return Pager(
-            PagingConfig(pageSize = 25),
-        ) {
-            getRemoteManga.subscribe(sourceId, currentFilter.query ?: "", currentFilter.filters)
-        }.flow
-            .map { pagingData ->
-                pagingData.map { sManga ->
-                    val dbManga = withIOContext { networkToLocalManga.await(sManga.toDomainManga(sourceId)) }
-                    getManga.subscribe(dbManga.url, dbManga.source)
-                        .filterNotNull()
-                        .onEach { initializeManga(it) }
-                        .stateIn(coroutineScope)
-                }
-            }
-            .cachedIn(coroutineScope)
-    }
-
     fun reset() {
         mutableState.update { it.copy(filters = source.getFilterList()) }
     }