pref: Use Paging3 for changelogs instead of custom pagination

app/build.gradle.kts

@@ -38,6 +38,7 @@ dependencies {
     implementation(libs.compose.material.icons.extended)
     implementation(libs.compose.material3)
     implementation(libs.navigation.compose)
+    implementation(libs.paging3)
 
     // Accompanist
     implementation(libs.accompanist.drawablepainter)

app/src/main/java/app/revanced/manager/domain/repository/ChangelogsRepository.kt

@@ -2,6 +2,8 @@ package app.revanced.manager.domain.repository
 
 import android.os.Parcelable
 import androidx.core.net.toUri
+import androidx.paging.PagingSource
+import androidx.paging.PagingState
 import app.revanced.manager.network.api.ReVancedAPI
 import app.revanced.manager.network.dto.ReVancedAssetHistory
 import app.revanced.manager.network.utils.getOrThrow
@@ -18,50 +20,29 @@ sealed interface ChangelogSource : Parcelable {
 }
 
 class ChangelogsRepository(
-    private val api: ReVancedAPI
-) {
-    private var all: List<ReVancedAssetHistory> = emptyList()
-    private var page = 0
+    private val api: ReVancedAPI,
+    private val source: ChangelogSource,
+) : PagingSource<Int, ReVancedAssetHistory>() {
 
-    suspend fun loadInitial(
-        source: ChangelogSource,
-        pageSize: Int
-    ): PageResult<ReVancedAssetHistory> {
-        all = when (source) {
-            is ChangelogSource.Manager ->
-                api.getAppHistory().getOrThrow()
+    override suspend fun load(params: LoadParams<Int>): LoadResult<Int, ReVancedAssetHistory> {
+        return try {
+            val items = when (source) {
+                is ChangelogSource.Manager ->
+                    api.getAppHistory().getOrThrow()
 
-            is ChangelogSource.Patches ->
-                api.getPatchesHistory(source.baseUrl, source.prerelease).getOrThrow()
+                is ChangelogSource.Patches ->
+                    api.getPatchesHistory(source.baseUrl, source.prerelease).getOrThrow()
+            }
+
+            LoadResult.Page(
+                data = items,
+                prevKey = null,
+                nextKey = null
+            )
+        } catch (e: Exception) {
+            LoadResult.Error(e)
         }
-
-        page = 1
-
-        val items = all.take(pageSize)
-        return PageResult(
-            items = items,
-            hasMore = hasMore(pageSize)
-        )
     }
 
-    fun loadNext(pageSize: Int): PageResult<ReVancedAssetHistory> {
-        val items = all
-            .drop(page * pageSize)
-            .take(pageSize)
-
-        page++
-
-        return PageResult(
-            items = items,
-            hasMore = hasMore(pageSize)
-        )
-    }
-
-    private fun hasMore(pageSize: Int) =
-        page * pageSize < all.size
-}
-
-data class PageResult<T>(
-    val items: List<T>,
-    val hasMore: Boolean
-)
+    override fun getRefreshKey(state: PagingState<Int, ReVancedAssetHistory>): Int? = null
+}

app/src/main/java/app/revanced/manager/ui/component/ChangelogList.kt

@@ -31,85 +31,65 @@ import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
+import androidx.paging.LoadState
+import androidx.paging.compose.LazyPagingItems
 import app.revanced.manager.R
 import app.revanced.manager.network.dto.ReVancedAssetHistory
 import app.revanced.manager.util.relativeTime
 
-sealed interface ChangelogUiState {
-    data object Loading : ChangelogUiState
-    data class Error(val error: String) : ChangelogUiState
-    data class Success(
-        val changelogs: List<ReVancedAssetHistory>,
-        val hasMore: Boolean = false,
-        val isLoadingMore: Boolean = false,
-    ) : ChangelogUiState
-}
-
 @Composable
 fun ChangelogList(
-    state: ChangelogUiState,
-    onLoadMore: () -> Unit,
+    changelogs: LazyPagingItems<ReVancedAssetHistory>,
     modifier: Modifier = Modifier,
 ) {
-    val listState = rememberLazyListState()
-
-    val shouldLoadMore by remember {
-        derivedStateOf {
-            val lastVisible = listState.layoutInfo.visibleItemsInfo.lastOrNull()?.index ?: 0
-            val total = listState.layoutInfo.totalItemsCount
-            val canScroll = listState.canScrollForward || listState.canScrollBackward
-
-            (lastVisible >= total - 2 || !canScroll) && total > 0
-        }
-    }
-
-    LaunchedEffect(shouldLoadMore, state) {
-        if (shouldLoadMore) onLoadMore()
-    }
-
     Box(
-        modifier = modifier.then(Modifier.fillMaxSize()),
+        modifier = modifier.fillMaxSize(),
         contentAlignment = Alignment.Center
     ) {
-        when (state) {
-            is ChangelogUiState.Loading -> LoadingIndicator()
+        when {
+            changelogs.loadState.refresh is LoadState.Loading -> LoadingIndicator()
 
-            is ChangelogUiState.Error -> Text(
-                text = state.error,
+            changelogs.loadState.refresh is LoadState.Error -> {
+                val error = changelogs.loadState.refresh as LoadState.Error
+                Text(
+                    text = error.error.message ?: stringResource(R.string.changelog_download_fail),
+                    style = MaterialTheme.typography.titleLarge
+                )
+            }
+
+            changelogs.itemCount == 0 -> Text(
+                text = stringResource(R.string.no_changelogs_found),
                 style = MaterialTheme.typography.titleLarge
             )
 
-            is ChangelogUiState.Success -> {
-                if (state.changelogs.isEmpty()) {
-                    Text(
-                        text = stringResource(R.string.no_changelogs_found),
-                        style = MaterialTheme.typography.titleLarge
-                    )
-                } else {
-                    LazyColumnWithScrollbar(
-                        modifier = Modifier.fillMaxSize(),
-                        state = listState
-                    ) {
-                        items(
-                            items = state.changelogs,
-                            key = { it.version }
-                        ) { changelog ->
+            else -> {
+                val listState = rememberLazyListState()
+
+                LazyColumnWithScrollbar(
+                    modifier = Modifier.fillMaxSize(),
+                    state = listState
+                ) {
+                    items(
+                        count = changelogs.itemCount,
+                        key = { changelogs.peek(it)?.version ?: it }
+                    ) { index ->
+                        changelogs[index]?.let { changelog ->
                             ChangelogItem(
                                 changelog = changelog,
-                                showDivider = changelog != state.changelogs.last()
+                                showDivider = index < changelogs.itemCount - 1
                             )
                         }
+                    }
 
-                        if (state.isLoadingMore) {
-                            item(key = "loading_more") {
-                                Box(
-                                    modifier = Modifier
-                                        .fillMaxWidth()
-                                        .padding(16.dp),
-                                    contentAlignment = Alignment.Center
-                                ) {
-                                    CircularProgressIndicator()
-                                }
+                    if (changelogs.loadState.append is LoadState.Loading) {
+                        item(key = "loading_more") {
+                            Box(
+                                modifier = Modifier
+                                    .fillMaxWidth()
+                                    .padding(16.dp),
+                                contentAlignment = Alignment.Center
+                            ) {
+                                CircularProgressIndicator()
                             }
                         }
                     }

app/src/main/java/app/revanced/manager/ui/screen/UpdateScreen.kt

@@ -32,6 +32,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
+import androidx.paging.compose.collectAsLazyPagingItems
 import app.revanced.manager.R
 import app.revanced.manager.ui.component.AppTopBar
 import app.revanced.manager.ui.component.BottomContentBar
@@ -48,6 +49,7 @@ fun UpdateScreen(
     vm: UpdateViewModel = koinViewModel()
 ) {
     val scrollBehavior = TopAppBarDefaults.pinnedScrollBehavior(rememberTopAppBarState())
+    val changelogs = vm.changelogs.collectAsLazyPagingItems()
 
     val buttonConfig = when (vm.state) {
         State.CAN_DOWNLOAD -> Triple(
@@ -123,10 +125,7 @@ fun UpdateScreen(
                 )
             }
 
-            ChangelogList(
-                state = vm.changelogsState,
-                onLoadMore = vm::loadNextPage,
-            )
+            ChangelogList(changelogs = changelogs, modifier = Modifier.padding(paddingValues))
         }
     }
 }

app/src/main/java/app/revanced/manager/ui/screen/settings/update/ChangelogsSettingsScreen.kt

@@ -8,6 +8,7 @@ import androidx.compose.material3.rememberTopAppBarState
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.nestedscroll.nestedScroll
+import androidx.paging.compose.collectAsLazyPagingItems
 import app.revanced.manager.domain.repository.ChangelogSource
 import app.revanced.manager.ui.component.AppTopBar
 import app.revanced.manager.ui.component.ChangelogList
@@ -23,6 +24,7 @@ fun ChangelogsSettingsScreen(
     vm: ChangelogsViewModel = koinViewModel { parametersOf(source) }
 ) {
     val scrollBehavior = TopAppBarDefaults.pinnedScrollBehavior(rememberTopAppBarState())
+    val changelogs = vm.changelogs.collectAsLazyPagingItems()
 
     Scaffold(
         topBar = {
@@ -34,6 +36,6 @@ fun ChangelogsSettingsScreen(
         },
         modifier = Modifier.nestedScroll(scrollBehavior.nestedScrollConnection),
     ) { paddingValues ->
-        ChangelogList(modifier = Modifier.padding(paddingValues), state = vm.state, onLoadMore =vm::loadNextPage)
+        ChangelogList(changelogs = changelogs, modifier = Modifier.padding(paddingValues))
     }
 }

app/src/main/java/app/revanced/manager/ui/viewmodel/ChangelogsViewModel.kt

@@ -1,60 +1,26 @@
 package app.revanced.manager.ui.viewmodel
 
-import android.app.Application
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.setValue
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
-import app.revanced.manager.R
+import androidx.paging.Pager
+import androidx.paging.PagingConfig
+import androidx.paging.PagingData
+import androidx.paging.cachedIn
 import app.revanced.manager.domain.repository.ChangelogSource
 import app.revanced.manager.domain.repository.ChangelogsRepository
-import app.revanced.manager.ui.component.ChangelogUiState
-import app.revanced.manager.util.uiSafe
-import kotlinx.coroutines.launch
+import app.revanced.manager.network.api.ReVancedAPI
+import app.revanced.manager.network.dto.ReVancedAssetHistory
+import kotlinx.coroutines.flow.Flow
 
 class ChangelogsViewModel(
-    private val repository: ChangelogsRepository,
-    private val app: Application,
+    private val api: ReVancedAPI,
     private val source: ChangelogSource,
 ) : ViewModel() {
-
-    var state: ChangelogUiState by mutableStateOf(ChangelogUiState.Loading)
-        private set
-
-    private val pageSize = 2
-
-    init {
-        viewModelScope.launch {
-            uiSafe(app, R.string.changelog_download_fail, "Failed to download changelog") {
-                val result = repository.loadInitial(source, pageSize)
-
-                state = ChangelogUiState.Success(
-                    changelogs = result.items,
-                    hasMore = result.hasMore
-                )
-            }
-
-            if (state is ChangelogUiState.Loading) {
-                state = ChangelogUiState.Error(
-                    app.getString(R.string.changelog_download_fail)
-                )
-            }
-        }
-    }
-
-    fun loadNextPage() {
-        val current = state as? ChangelogUiState.Success ?: return
-        if (current.isLoadingMore || !current.hasMore) return
-
-        state = current.copy(isLoadingMore = true)
-
-        val result = repository.loadNext(pageSize)
-
-        state = current.copy(
-            changelogs = current.changelogs + result.items,
-            isLoadingMore = false,
-            hasMore = result.hasMore
-        )
-    }
+    val changelogs: Flow<PagingData<ReVancedAssetHistory>> = Pager(
+        config = PagingConfig(
+            pageSize = 10,
+            enablePlaceholders = false
+        ),
+        pagingSourceFactory = { ChangelogsRepository(api, source) }
+    ).flow.cachedIn(viewModelScope)
 }

app/src/main/java/app/revanced/manager/ui/viewmodel/UpdateViewModel.kt

@@ -10,6 +10,10 @@ import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.setValue
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
+import androidx.paging.Pager
+import androidx.paging.PagingConfig
+import androidx.paging.PagingData
+import androidx.paging.cachedIn
 import app.revanced.manager.R
 import app.revanced.manager.data.platform.Filesystem
 import app.revanced.manager.data.platform.NetworkInfo
@@ -17,13 +21,14 @@ import app.revanced.manager.domain.repository.ChangelogSource
 import app.revanced.manager.domain.repository.ChangelogsRepository
 import app.revanced.manager.network.api.ReVancedAPI
 import app.revanced.manager.network.dto.ReVancedAsset
+import app.revanced.manager.network.dto.ReVancedAssetHistory
 import app.revanced.manager.network.service.HttpService
-import app.revanced.manager.ui.component.ChangelogUiState
 import app.revanced.manager.util.toast
 import app.revanced.manager.util.uiSafe
 import io.ktor.client.plugins.onDownload
 import io.ktor.client.request.url
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import org.koin.core.component.KoinComponent
@@ -37,7 +42,8 @@ import ru.solrudev.ackpine.session.await
 import ru.solrudev.ackpine.session.parameters.Confirmation
 
 class UpdateViewModel(
-    private val changelogsRepository: ChangelogsRepository,
+    private val api: ReVancedAPI,
+    private val source: ChangelogSource,
     private val downloadOnScreenEntry: Boolean
 ) : ViewModel(), KoinComponent {
     private val app: Application by inject()
@@ -66,8 +72,13 @@ class UpdateViewModel(
     var releaseInfo: ReVancedAsset? by mutableStateOf(null)
         private set
 
-    var changelogsState: ChangelogUiState by mutableStateOf(ChangelogUiState.Loading)
-    private val changelogsPageSize = 2
+    val changelogs: Flow<PagingData<ReVancedAssetHistory>> = Pager(
+        config = PagingConfig(
+            pageSize = 10,
+            enablePlaceholders = false
+        ),
+        pagingSourceFactory = { ChangelogsRepository(api, source) }
+    ).flow.cachedIn(viewModelScope)
 
     private val location = fs.tempDir.resolve("updater.apk")
 
@@ -77,44 +88,14 @@ class UpdateViewModel(
                 releaseInfo = reVancedAPI.getAppUpdate()
                     ?: throw Exception("No update available")
 
-                val result = changelogsRepository.loadInitial(
-                    ChangelogSource.Manager,
-                    changelogsPageSize
-                )
-
-                changelogsState = ChangelogUiState.Success(
-                    changelogs = result.items,
-                    hasMore = result.hasMore
-                )
-
                 if (downloadOnScreenEntry) {
                     downloadUpdate()
                 } else {
                     state = State.CAN_DOWNLOAD
                 }
             }
-
-            if (changelogsState is ChangelogUiState.Loading) {
-                changelogsState = ChangelogUiState.Error(
-                    app.getString(R.string.changelog_download_fail)
-                )
-            }
         }
     }
-    fun loadNextPage() {
-        val current = changelogsState as? ChangelogUiState.Success ?: return
-        if (current.isLoadingMore || !current.hasMore) return
-
-        changelogsState = current.copy(isLoadingMore = true)
-
-        val result = changelogsRepository.loadNext(changelogsPageSize)
-
-        changelogsState = current.copy(
-            changelogs = current.changelogs + result.items,
-            isLoadingMore = false,
-            hasMore = result.hasMore
-        )
-    }
 
     fun downloadUpdate(ignoreInternetCheck: Boolean = false) = viewModelScope.launch {
         uiSafe(app, R.string.failed_to_download_update, "Failed to download update") {

gradle/libs.versions.toml

@@ -40,6 +40,7 @@ binary-compatibility-validator = "0.18.1"
 semver-parser = "3.0.0"
 ackpine = "0.20.6"
 foundation-layout = "1.10.5"
+paging3 = "3.4.2"
 
 [libraries]
 # AndroidX Core
@@ -62,6 +63,7 @@ compose-livedata = { group = "androidx.compose.runtime", name = "runtime-livedat
 compose-material3 = { group = "androidx.compose.material3", name = "material3", version.ref = "material3" }
 compose-material-icons-extended = { group = "androidx.compose.material", name = "material-icons-extended" }
 navigation-compose = { group = "androidx.navigation", name = "navigation-compose", version.ref = "navigation" }
+paging3 = { group = "androidx.paging", name = "paging-compose", version.ref = "paging3" }
 
 # Coil
 coil-compose = { group = "io.coil-kt", name = "coil-compose", version.ref = "coil" }