Optimize WorkflowScreen by Paging

SanmerApps · Aug 2, 2024 · 706ad54 · 706ad54
1 parent 8ac848d
commit 706ad54
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Showing 6 changed files with 108 additions and 55 deletions.
diff --git a/app/build.gradle.kts b/app/build.gradle.kts
@@ -91,6 +91,8 @@ dependencies {
     implementation(libs.androidx.lifecycle.viewmodel)
     implementation(libs.androidx.lifecycle.viewmodel.savedstate)
     implementation(libs.androidx.navigation.compose)
+    implementation(libs.androidx.paging.compose)
+    implementation(libs.androidx.paging.runtime)
     implementation(libs.kotlinx.coroutines.android)
     implementation(libs.kotlinx.datetime)
     implementation(libs.kotlinx.serialization.json)

diff --git a/app/src/main/kotlin/dev/sanmer/github/artifacts/ui/ktx/PagingExt.kt b/app/src/main/kotlin/dev/sanmer/github/artifacts/ui/ktx/PagingExt.kt
@@ -0,0 +1,21 @@
+package dev.sanmer.github.artifacts.ui.ktx
+
+import androidx.compose.foundation.lazy.LazyItemScope
+import androidx.compose.foundation.lazy.LazyListScope
+import androidx.compose.runtime.Composable
+import androidx.paging.compose.LazyPagingItems
+import androidx.paging.compose.itemContentType
+import androidx.paging.compose.itemKey
+
+inline fun <T : Any> LazyListScope.items(
+    items: LazyPagingItems<T>,
+    noinline key: ((T) -> Any)? = null,
+    noinline contentType: (T) -> Any? = { null },
+    crossinline itemContent: @Composable LazyItemScope.(item: T) -> Unit
+) = items(
+    count = items.itemCount,
+    key = items.itemKey(key),
+    contentType = items.itemContentType(contentType)
+) {
+    itemContent(items[it]!!)
+}
diff --git a/app/src/main/kotlin/dev/sanmer/github/artifacts/ui/screen/workflow/WorkflowScreen.kt b/app/src/main/kotlin/dev/sanmer/github/artifacts/ui/screen/workflow/WorkflowScreen.kt
@@ -9,16 +9,14 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.material3.TopAppBarScrollBehavior
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.res.painterResource
-import androidx.compose.ui.res.stringResource
 import androidx.hilt.navigation.compose.hiltViewModel
-import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.navigation.NavController
+import androidx.paging.LoadState
+import androidx.paging.compose.collectAsLazyPagingItems
 import dev.sanmer.github.artifacts.R
-import dev.sanmer.github.artifacts.model.LoadData
 import dev.sanmer.github.artifacts.ui.component.Failed
 import dev.sanmer.github.artifacts.ui.component.Loading
 import dev.sanmer.github.artifacts.ui.component.NavigateUpTopBar
@@ -30,14 +28,14 @@ fun WorkflowScreen(
     viewModel: WorkflowViewModel = hiltViewModel(),
     navController: NavController
 ) {
-    val workflowRuns by viewModel.workflowRuns.collectAsStateWithLifecycle()
+    val workflowRuns = viewModel.workflowRuns.collectAsLazyPagingItems()
     val scrollBehavior = TopAppBarDefaults.pinnedScrollBehavior()
 
     Scaffold(
         topBar = {
             TopBar(
                 name = viewModel.name,
-                onRefresh = viewModel::updateWorkflows,
+                onRefresh = workflowRuns::refresh,
                 navController = navController,
                 scrollBehavior = scrollBehavior
             )
@@ -47,32 +45,25 @@ fun WorkflowScreen(
             modifier = Modifier
                 .nestedScroll(scrollBehavior.nestedScrollConnection)
                 .fillMaxSize(),
-            targetState = workflowRuns,
+            targetState = workflowRuns.loadState.refresh,
             label = "WorkflowScreen"
-        ) { data ->
-            when (data) {
-                LoadData.Loading, LoadData.None -> Loading(
+        ) { state ->
+            when (state) {
+                is LoadState.Error -> Failed(
+                    message = state.error.message,
                     modifier = Modifier.padding(contentPadding)
                 )
 
-                is LoadData.Failure -> Failed(
-                    message = data.error.message,
+                is LoadState.Loading -> Loading(
                     modifier = Modifier.padding(contentPadding)
                 )
 
-                is LoadData.Success -> if (data.value.isEmpty()) {
-                    Failed(
-                        message = stringResource(id = R.string.no_workflow),
-                        modifier = Modifier.padding(contentPadding)
-                    )
-                } else {
-                    WorkflowList(
-                        workflowRuns = data.value,
-                        getArtifacts = viewModel::getArtifacts,
-                        downloadArtifact = viewModel::downloadArtifact,
-                        contentPadding = contentPadding
-                    )
-                }
+                else -> WorkflowList(
+                    workflowRuns = workflowRuns,
+                    getArtifacts = viewModel::getArtifacts,
+                    downloadArtifact = viewModel::downloadArtifact,
+                    contentPadding = contentPadding
+                )
             }
         }
     }

diff --git a/app/src/main/kotlin/dev/sanmer/github/artifacts/ui/screen/workflow/component/WorkflowList.kt b/app/src/main/kotlin/dev/sanmer/github/artifacts/ui/screen/workflow/component/WorkflowList.kt
@@ -12,7 +12,6 @@ import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.LazyListState
-import androidx.compose.foundation.lazy.items
 import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.CircularProgressIndicator
@@ -34,15 +33,17 @@ import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.paging.compose.LazyPagingItems
 import dev.sanmer.github.artifacts.R
 import dev.sanmer.github.artifacts.job.ArtifactJob
 import dev.sanmer.github.artifacts.model.LoadData
+import dev.sanmer.github.artifacts.ui.ktx.items
 import dev.sanmer.github.response.Artifact
 import dev.sanmer.github.response.WorkflowRun
 
 @Composable
 fun WorkflowList(
-    workflowRuns: List<WorkflowRun>,
+    workflowRuns: LazyPagingItems<WorkflowRun>,
     getArtifacts: (WorkflowRun) -> LoadData<List<Artifact>>,
     downloadArtifact: (Context, Artifact) -> Unit,
     state: LazyListState = rememberLazyListState(),
@@ -56,7 +57,10 @@ fun WorkflowList(
     horizontalAlignment = Alignment.CenterHorizontally,
     verticalArrangement = Arrangement.spacedBy(5.dp)
 ) {
-    items(workflowRuns) { run ->
+    items(
+        items = workflowRuns,
+        key = { it.id }
+    ) { run ->
         WorkflowItem(
             run = run,
             getArtifacts = getArtifacts,

diff --git a/app/src/main/kotlin/dev/sanmer/github/artifacts/viewmodel/WorkflowViewModel.kt b/app/src/main/kotlin/dev/sanmer/github/artifacts/viewmodel/WorkflowViewModel.kt
@@ -8,6 +8,12 @@ import androidx.compose.runtime.setValue
 import androidx.lifecycle.SavedStateHandle
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
+import androidx.paging.Pager
+import androidx.paging.PagingConfig
+import androidx.paging.PagingData
+import androidx.paging.PagingSource
+import androidx.paging.PagingState
+import androidx.paging.cachedIn
 import dagger.hilt.android.lifecycle.HiltViewModel
 import dev.sanmer.github.GitHubHandler
 import dev.sanmer.github.GitHubHandler.Event
@@ -18,9 +24,8 @@ import dev.sanmer.github.artifacts.model.LoadData.None.asLoadData
 import dev.sanmer.github.artifacts.repository.DbRepository
 import dev.sanmer.github.response.Artifact
 import dev.sanmer.github.response.WorkflowRun
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.asStateFlow
-import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.emptyFlow
 import kotlinx.coroutines.launch
 import timber.log.Timber
 import javax.inject.Inject
@@ -38,8 +43,8 @@ class WorkflowViewModel @Inject constructor(
     private var token = ""
     private val handler by lazy { GitHubHandler(token) }
 
-    private val workflowRunsFlow = MutableStateFlow<LoadData<List<WorkflowRun>>>(LoadData.Loading)
-    val workflowRuns get() = workflowRunsFlow.asStateFlow()
+    var workflowRuns: Flow<PagingData<WorkflowRun>> = emptyFlow()
+        private set
 
     private val artifacts = mutableStateMapOf<Long, LoadData<List<Artifact>>>()
 
@@ -56,33 +61,17 @@ class WorkflowViewModel @Inject constructor(
                     owner = repo.owner
                     name = repo.name
 
-                    listWorkflows()
-                }
-        }
-    }
-
-    private fun listWorkflows() = with(handler) {
-        viewModelScope.launch {
-            workflowRunsFlow.update {
-                runCatching {
-                    listWorkflowRuns(
+                    workflowRuns = WorkflowRunPagingSource(
+                        handler = handler,
                         owner = owner,
                         name = name,
-                        event = Event.Push,
-                        status = Status.Success,
-                        perPage = 30,
-                        page = 1
-                    )
-                }.asLoadData()
-            }
+                        perPage = 20
+                    ).asPager().flow
+                        .cachedIn(this)
+                }
         }
     }
 
-    fun updateWorkflows() {
-        workflowRunsFlow.update { LoadData.Loading }
-        listWorkflows()
-    }
-
     fun getArtifacts(run: WorkflowRun) = with(handler) {
         viewModelScope.launch {
             artifacts.getOrPut(run.id) {
@@ -107,6 +96,49 @@ class WorkflowViewModel @Inject constructor(
         )
     }
 
+    data class WorkflowRunPagingSource(
+        private val handler: GitHubHandler,
+        private val owner: String,
+        private val name: String,
+        private val event: Event = Event.Push,
+        private val status: Status = Status.Success,
+        private val perPage: Int = 30
+    ) : PagingSource<Int, WorkflowRun>() {
+        override fun getRefreshKey(state: PagingState<Int, WorkflowRun>): Int? {
+            return state.anchorPosition?.let { anchorPosition ->
+                state.closestPageToPosition(anchorPosition)?.prevKey?.plus(1)
+                    ?: state.closestPageToPosition(anchorPosition)?.nextKey?.minus(1)
+            }
+        }
+
+        override suspend fun load(params: LoadParams<Int>): LoadResult<Int, WorkflowRun> {
+            return try {
+                val page = params.key ?: 1
+                val workflowRuns = handler.listWorkflowRuns(
+                    owner = owner,
+                    name = name,
+                    event = event,
+                    status = status,
+                    perPage = perPage,
+                    page = page
+                )
+
+                LoadResult.Page(
+                    data = workflowRuns,
+                    prevKey = if (page == 1) null else page.minus(1),
+                    nextKey = if (workflowRuns.size != perPage) null else page.plus(1),
+                )
+            } catch (e: Exception) {
+                LoadResult.Error(e)
+            }
+        }
+
+        fun asPager() = Pager(
+            config = PagingConfig(pageSize = perPage),
+            pagingSourceFactory = { copy() }
+        )
+    }
+
     companion object Util {
         private val SavedStateHandle.id: Long
             inline get() = checkNotNull(get("id"))

diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
@@ -10,6 +10,7 @@ androidxCoreSplashscreen = "1.0.1"
 androidxHiltNavigationCompose = "1.2.0"
 androidxLifecycle = "2.8.4"
 androidxNavigation = "2.7.7"
+androidxPaging = "3.3.1"
 androidxRoom = "2.6.1"
 hilt = "2.51.1"
 kotlin = "2.0.0"
@@ -43,6 +44,8 @@ androidx-lifecycle-service = { module = "androidx.lifecycle:lifecycle-service",
 androidx-lifecycle-viewmodel = { module = "androidx.lifecycle:lifecycle-viewmodel-ktx", version.ref = "androidxLifecycle" }
 androidx-lifecycle-viewmodel-savedstate = { module = "androidx.lifecycle:lifecycle-viewmodel-savedstate", version.ref = "androidxLifecycle" }
 androidx-navigation-compose = { module = "androidx.navigation:navigation-compose", version.ref = "androidxNavigation" }
+androidx-paging-compose = { module = "androidx.paging:paging-compose", version.ref = "androidxPaging" }
+androidx-paging-runtime = { module = "androidx.paging:paging-runtime", version.ref = "androidxPaging" }
 androidx-room-compiler = { module = "androidx.room:room-compiler", version.ref = "androidxRoom" }
 androidx-room-ktx = { module = "androidx.room:room-ktx", version.ref = "androidxRoom" }
 androidx-room-runtime = { module = "androidx.room:room-runtime", version.ref = "androidxRoom" }