Merge branch 'main' into mv/collectAsState

.github/workflows/Build.yaml

@@ -117,7 +117,7 @@ jobs:
           disable-animations: true
           disk-size: 1500M
           heap-size: 512M
-          script: ./gradlew connectedProdDebugAndroidTest -x :benchmark:connectedBenchmarkAndroidTest
+          script: ./gradlew connectedProdDebugAndroidTest -x :benchmark:connectedProdBenchmarkAndroidTest --stacktrace
 
       - name: Upload test reports
         if: always()

app/build.gradle.kts

@@ -24,6 +24,7 @@ plugins {
     id("jacoco")
     id("dagger.hilt.android.plugin")
     id("nowinandroid.spotless")
+    id("nowinandroid.firebase-perf")
 }
 
 android {
@@ -62,8 +63,6 @@ android {
             proguardFiles("benchmark-rules.pro")
             //  FIXME enabling minification breaks access to demo backend.
             isMinifyEnabled = false
-            // Keep the build type debuggable so we can attach a debugger if needed.
-            isDebuggable = true
             applicationIdSuffix = ".benchmark"
         }
     }

app/src/main/java/com/google/samples/apps/nowinandroid/MainActivity.kt

@@ -22,12 +22,21 @@ import androidx.activity.compose.setContent
 import androidx.compose.material3.windowsizeclass.ExperimentalMaterial3WindowSizeClassApi
 import androidx.compose.material3.windowsizeclass.calculateWindowSizeClass
 import androidx.core.view.WindowCompat
+import androidx.metrics.performance.JankStats
 import com.google.samples.apps.nowinandroid.ui.NiaApp
 import dagger.hilt.android.AndroidEntryPoint
+import javax.inject.Inject
 
 @OptIn(ExperimentalMaterial3WindowSizeClassApi::class)
 @AndroidEntryPoint
 class MainActivity : ComponentActivity() {
+
+    /**
+     * Lazily inject [JankStats], which is used to track jank throughout the app.
+     */
+    @Inject
+    lateinit var lazyStats: dagger.Lazy<JankStats>
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
@@ -35,6 +44,18 @@ class MainActivity : ComponentActivity() {
         // including IME animations
         WindowCompat.setDecorFitsSystemWindows(window, false)
 
-        setContent { NiaApp(calculateWindowSizeClass(this)) }
+        setContent {
+            NiaApp(calculateWindowSizeClass(this))
+        }
+    }
+
+    override fun onResume() {
+        super.onResume()
+        lazyStats.get().isTrackingEnabled = true
+    }
+
+    override fun onPause() {
+        super.onPause()
+        lazyStats.get().isTrackingEnabled = false
     }
 }

app/src/main/java/com/google/samples/apps/nowinandroid/di/JankStatsModule.kt

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.samples.apps.nowinandroid.di
+
+import android.app.Activity
+import android.util.Log
+import android.view.Window
+import androidx.metrics.performance.JankStats
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.components.ActivityComponent
+import java.util.concurrent.Executor
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.asExecutor
+
+@Module
+@InstallIn(ActivityComponent::class)
+object JankStatsModule {
+    @Provides
+    fun providesOnFrameListener(): JankStats.OnFrameListener {
+        return JankStats.OnFrameListener { frameData ->
+            // Make sure to only log janky frames.
+            if (frameData.isJank) {
+                // We're currently logging this but would better report it to a backend.
+                Log.v("NiA Jank", frameData.toString())
+            }
+        }
+    }
+
+    @Provides
+    fun providesWindow(activity: Activity): Window {
+        return activity.window
+    }
+
+    @Provides
+    fun providesDefaultExecutor(): Executor {
+        return Dispatchers.Default.asExecutor()
+    }
+
+    @Provides
+    fun providesJankStats(
+        window: Window,
+        executor: Executor,
+        frameListener: JankStats.OnFrameListener
+    ): JankStats {
+        return JankStats.createAndTrack(window, executor, frameListener)
+    }
+}

app/src/main/java/com/google/samples/apps/nowinandroid/navigation/NiaTopLevelNavigation.kt

@@ -18,6 +18,7 @@ package com.google.samples.apps.nowinandroid.navigation
 
 import androidx.navigation.NavGraph.Companion.findStartDestination
 import androidx.navigation.NavHostController
+import androidx.tracing.trace
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.Icon
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.Icon.DrawableResourceIcon
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.Icon.ImageVectorIcon
@@ -39,18 +40,20 @@ import com.google.samples.apps.nowinandroid.feature.interests.navigation.Interes
 class NiaTopLevelNavigation(private val navController: NavHostController) {
 
     fun navigateTo(destination: TopLevelDestination) {
-        navController.navigate(destination.route) {
+        trace("Navigation: $destination") {
-            // Pop up to the start destination of the graph to
+            navController.navigate(destination.route) {
-            // avoid building up a large stack of destinations
+                // Pop up to the start destination of the graph to
-            // on the back stack as users select items
+                // avoid building up a large stack of destinations
-            popUpTo(navController.graph.findStartDestination().id) {
+                // on the back stack as users select items
-                saveState = true
+                popUpTo(navController.graph.findStartDestination().id) {
+                    saveState = true
+                }
+                // Avoid multiple copies of the same destination when
+                // reselecting the same item
+                launchSingleTop = true
+                // Restore state when reselecting a previously selected item
+                restoreState = true
             }
-            // Avoid multiple copies of the same destination when
-            // reselecting the same item
-            launchSingleTop = true
-            // Restore state when reselecting a previously selected item
-            restoreState = true
         }
     }
 }

app/src/main/java/com/google/samples/apps/nowinandroid/ui/NiaApp.kt

@@ -39,10 +39,14 @@ import androidx.compose.material3.windowsizeclass.WindowWidthSizeClass
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
+import androidx.compose.ui.ExperimentalComposeUiApi
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.semantics.semantics
+import androidx.compose.ui.semantics.testTagsAsResourceId
+import androidx.navigation.NavController
 import androidx.navigation.NavDestination
 import androidx.navigation.NavDestination.Companion.hierarchy
 import androidx.navigation.compose.currentBackStackEntryAsState
@@ -55,12 +59,17 @@ import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaNavig
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.Icon.DrawableResourceIcon
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.Icon.ImageVectorIcon
 import com.google.samples.apps.nowinandroid.core.designsystem.theme.NiaTheme
+import com.google.samples.apps.nowinandroid.core.ui.JankMetricDisposableEffect
 import com.google.samples.apps.nowinandroid.navigation.NiaNavHost
 import com.google.samples.apps.nowinandroid.navigation.NiaTopLevelNavigation
 import com.google.samples.apps.nowinandroid.navigation.TOP_LEVEL_DESTINATIONS
 import com.google.samples.apps.nowinandroid.navigation.TopLevelDestination
 
-@OptIn(ExperimentalMaterial3Api::class, ExperimentalLayoutApi::class)
+@OptIn(
+    ExperimentalMaterial3Api::class,
+    ExperimentalLayoutApi::class,
+    ExperimentalComposeUiApi::class
+)
 @Composable
 fun NiaApp(windowSizeClass: WindowSizeClass) {
     NiaTheme {
@@ -74,7 +83,9 @@ fun NiaApp(windowSizeClass: WindowSizeClass) {
 
         NiaBackground {
             Scaffold(
-                modifier = Modifier,
+                modifier = Modifier.semantics {
+                    testTagsAsResourceId = true
+                },
                 containerColor = Color.Transparent,
                 contentColor = MaterialTheme.colorScheme.onBackground,
                 bottomBar = {
@@ -117,6 +128,17 @@ fun NiaApp(windowSizeClass: WindowSizeClass) {
                 }
             }
         }
+        JankMetricDisposableEffect(navController) { metricsHolder ->
+            val listener = NavController.OnDestinationChangedListener { _, destination, _ ->
+                metricsHolder.state?.addState("Navigation", destination.route.toString())
+            }
+
+            navController.addOnDestinationChangedListener(listener)
+
+            onDispose {
+                navController.removeOnDestinationChangedListener(listener)
+            }
+        }
     }
 }
 

benchmark/build.gradle.kts

@@ -13,6 +13,9 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+import com.google.samples.apps.nowinandroid.Flavor
+import com.google.samples.apps.nowinandroid.FlavorDimension
+import com.google.samples.apps.nowinandroid.configureFlavors
 
 plugins {
     id("nowinandroid.android.test")
@@ -25,7 +28,6 @@ android {
     defaultConfig {
         minSdk = 23
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
-        missingDimensionStrategy("contentType", "demo")
     }
 
     buildTypes {
@@ -33,12 +35,18 @@ android {
         // release build (for example, with minification on). It's signed with a debug key
         // for easy local/CI testing.
         val benchmark by creating {
-            isDebuggable = false
+            // Keep the build type debuggable so we can attach a debugger if needed.
+            isDebuggable = true
             signingConfig = signingConfigs.getByName("debug")
             matchingFallbacks.add("release")
         }
     }
 
+    // Use the same flavor dimensions as the application to allow generating Baseline Profiles on prod,
+    // which is more close to what will be shipped to users (no fake data), but has ability to run the
+    // benchmarks on demo, so we benchmark on stable data. 
+    configureFlavors(this)
+    
     targetProjectPath = ":app"
     experimentalProperties["android.experimental.self-instrumenting"] = true
 }

benchmark/src/main/java/com/google/samples/apps/nowinandroid/Utils.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.samples.apps.nowinandroid
+
+import com.google.samples.apps.nowinandroid.benchmark.BuildConfig
+
+/**
+ * Convenience parameter to use proper package name with regards to build type and build flavor.
+ */
+const val PACKAGE_NAME =
+    "com.google.samples.apps.nowinandroid.${BuildConfig.FLAVOR}.${BuildConfig.BUILD_TYPE}"

benchmark/src/main/java/com/google/samples/apps/nowinandroid/baselineprofile/BaselineProfileGenerator.kt

@@ -19,7 +19,12 @@ package com.google.samples.apps.nowinandroid.baselineprofile
 import androidx.benchmark.macro.ExperimentalBaselineProfilesApi
 import androidx.benchmark.macro.junit4.BaselineProfileRule
 import androidx.test.uiautomator.By
-import androidx.test.uiautomator.Direction
+import com.google.samples.apps.nowinandroid.PACKAGE_NAME
+import com.google.samples.apps.nowinandroid.foryou.forYouScrollFeedDownUp
+import com.google.samples.apps.nowinandroid.foryou.forYouSelectAuthors
+import com.google.samples.apps.nowinandroid.foryou.forYouWaitForContent
+import com.google.samples.apps.nowinandroid.interests.interestsScrollPeopleDownUp
+import com.google.samples.apps.nowinandroid.interests.interestsScrollTopicsDownUp
 import org.junit.Rule
 import org.junit.Test
 
@@ -31,27 +36,30 @@ class BaselineProfileGenerator {
     @get:Rule val baselineProfileRule = BaselineProfileRule()
 
     @Test
-    fun startup() =
+    fun generate() =
-        baselineProfileRule.collectBaselineProfile(
+        baselineProfileRule.collectBaselineProfile(PACKAGE_NAME) {
-            packageName = "com.google.samples.apps.nowinandroid.demo.benchmark"
-        ) {
-            pressHome()
             // This block defines the app's critical user journey. Here we are interested in
             // optimizing for app startup. But you can also navigate and scroll
             // through your most important UI.
+
+            pressHome()
             startActivityAndWait()
+
+            // Scroll the feed critical user journey
+            forYouWaitForContent()
+            forYouSelectAuthors()
+            forYouScrollFeedDownUp()
+
+            // Navigate to interests screen
+            device.findObject(By.text("Interests")).click()
+            device.waitForIdle()
+
+            interestsScrollTopicsDownUp()
+
+            // Navigate to people tab
+            device.findObject(By.text("People")).click()
             device.waitForIdle()
 
-            device.run {
+            interestsScrollPeopleDownUp()
-                findObject(By.text("Interests"))
-                    .click()
-                waitForIdle()
-                findObject(By.text("Accessibility")).scroll(Direction.DOWN, 2000f)
-                waitForIdle()
-                findObject(By.text("People")).click()
-                waitForIdle()
-                findObject(By.textStartsWith("Android")).scroll(Direction.DOWN, 2000f)
-                waitForIdle()
-            }
         }
 }

benchmark/src/main/java/com/google/samples/apps/nowinandroid/foryou/ForYouActions.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.samples.apps.nowinandroid.foryou
+
+import androidx.benchmark.macro.MacrobenchmarkScope
+import androidx.test.uiautomator.By
+import androidx.test.uiautomator.Direction
+import androidx.test.uiautomator.Until
+
+fun MacrobenchmarkScope.forYouWaitForContent() {
+    // Wait until content is loaded
+    device.wait(Until.hasObject(By.text("What are you interested in?")), 30_000)
+}
+
+fun MacrobenchmarkScope.forYouSelectAuthors() {
+    val authors = device.findObject(By.res("forYou:authors"))
+    // select some authors to show some feed content
+    repeat(3) { index ->
+        val author = authors.children[index % authors.childCount]
+        author.click()
+        device.waitForIdle()
+    }
+}
+
+fun MacrobenchmarkScope.forYouScrollFeedDownUp() {
+    val feedList = device.findObject(By.res("forYou:feed"))
+    feedList.fling(Direction.DOWN)
+    device.waitForIdle()
+    feedList.fling(Direction.UP)
+}

benchmark/src/main/java/com/google/samples/apps/nowinandroid/foryou/ScrollForYouFeedBenchmark.kt

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.samples.apps.nowinandroid.foryou
+
+import androidx.benchmark.macro.CompilationMode
+import androidx.benchmark.macro.FrameTimingMetric
+import androidx.benchmark.macro.StartupMode
+import androidx.benchmark.macro.junit4.MacrobenchmarkRule
+import androidx.test.internal.runner.junit4.AndroidJUnit4ClassRunner
+import com.google.samples.apps.nowinandroid.PACKAGE_NAME
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4ClassRunner::class)
+class ScrollForYouFeedBenchmark {
+    @get:Rule
+    val benchmarkRule = MacrobenchmarkRule()
+
+    @Test
+    fun scrollFeedCompilationNone() = scrollFeed(CompilationMode.None())
+
+    @Test
+    fun scrollFeedCompilationBaselineProfile() = scrollFeed(CompilationMode.Partial())
+
+    private fun scrollFeed(compilationMode: CompilationMode) = benchmarkRule.measureRepeated(
+        packageName = PACKAGE_NAME,
+        metrics = listOf(FrameTimingMetric()),
+        compilationMode = compilationMode,
+        iterations = 10,
+        startupMode = StartupMode.COLD,
+        setupBlock = {
+            // Start the app
+            pressHome()
+            startActivityAndWait()
+        }
+    ) {
+        forYouWaitForContent()
+        forYouSelectAuthors()
+        forYouScrollFeedDownUp()
+    }
+}

benchmark/src/main/java/com/google/samples/apps/nowinandroid/interests/InterestsActions.kt

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.samples.apps.nowinandroid.interests
+
+import androidx.benchmark.macro.MacrobenchmarkScope
+import androidx.test.uiautomator.By
+import androidx.test.uiautomator.Direction
+
+fun MacrobenchmarkScope.interestsScrollTopicsDownUp() {
+    val topicsList = device.findObject(By.res("interests:topics"))
+    topicsList.fling(Direction.DOWN)
+    device.waitForIdle()
+    topicsList.fling(Direction.UP)
+}
+
+fun MacrobenchmarkScope.interestsScrollPeopleDownUp() {
+    val peopleList = device.findObject(By.res("interests:people"))
+    peopleList.fling(Direction.DOWN)
+    device.waitForIdle()
+    peopleList.fling(Direction.UP)
+}

benchmark/src/main/java/com/google/samples/apps/nowinandroid/startup/StartupBenchmark.kt

@@ -26,6 +26,8 @@ import androidx.benchmark.macro.StartupMode.WARM
 import androidx.benchmark.macro.StartupTimingMetric
 import androidx.benchmark.macro.junit4.MacrobenchmarkRule
 import androidx.test.internal.runner.junit4.AndroidJUnit4ClassRunner
+import com.google.samples.apps.nowinandroid.PACKAGE_NAME
+import com.google.samples.apps.nowinandroid.foryou.forYouWaitForContent
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -74,7 +76,7 @@ abstract class AbstractStartupBenchmark(private val startupMode: StartupMode) {
     fun startupFullCompilation() = startup(CompilationMode.Full())
 
     private fun startup(compilationMode: CompilationMode) = benchmarkRule.measureRepeated(
-        packageName = "com.google.samples.apps.nowinandroid",
+        packageName = PACKAGE_NAME,
         metrics = listOf(StartupTimingMetric()),
         compilationMode = compilationMode,
         iterations = 10,
@@ -84,5 +86,7 @@ abstract class AbstractStartupBenchmark(private val startupMode: StartupMode) {
         }
     ) {
         startActivityAndWait()
+        // Waits until the content is ready to capture Time To Full Display
+        forYouWaitForContent()
     }
 }

build-logic/convention/build.gradle.kts

@@ -69,5 +69,9 @@ gradlePlugin {
             id = "nowinandroid.spotless"
             implementationClass = "SpotlessConventionPlugin"
         }
+        register("firebase-perf") {
+            id = "nowinandroid.firebase-perf"
+            implementationClass = "FirebasePerfConventionPlugin"
+        }
     }
 }

build-logic/convention/src/main/kotlin/FirebasePerfConventionPlugin.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ *   Licensed under the Apache License, Version 2.0 (the "License");
+ *   you may not use this file except in compliance with the License.
+ *   You may obtain a copy of the License at
+ *
+ *       https://www.apache.org/licenses/LICENSE-2.0
+ *
+ *   Unless required by applicable law or agreed to in writing, software
+ *   distributed under the License is distributed on an "AS IS" BASIS,
+ *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *   See the License for the specific language governing permissions and
+ *   limitations under the License.
+ */
+
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+
+class FirebasePerfConventionPlugin : Plugin<Project> {
+    override fun apply(target: Project) {
+        with(target) {
+            pluginManager.findPlugin("com.google.firebase.firebase-perf").apply {
+                version = "1.4.1"
+            }
+        }
+    }
+
+}

build-logic/convention/src/main/kotlin/com/google/samples/apps/nowinandroid/AndroidCompose.kt

@@ -36,7 +36,7 @@ internal fun Project.configureAndroidCompose(
         }
 
         composeOptions {
-            kotlinCompilerExtensionVersion = libs.findVersion("androidxCompose").get().toString()
+            kotlinCompilerExtensionVersion = libs.findVersion("androidxComposeCompiler").get().toString()
         }
 
         kotlinOptions {

build-logic/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.2-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

core-datastore/build.gradle.kts

@@ -70,3 +70,8 @@ dependencies {
     kapt(libs.hilt.compiler)
     kaptAndroidTest(libs.hilt.compiler)
 }
+
+// TODO b/239411851, Remove kapt workaround configuration
+kapt {
+    correctErrorTypes = true
+}

core-ui/build.gradle.kts

@@ -45,4 +45,6 @@ dependencies {
     api(libs.androidx.compose.ui.util)
     api(libs.androidx.compose.runtime)
     api(libs.androidx.compose.runtime.livedata)
+    api(libs.androidx.metrics)
+    api(libs.androidx.tracing.ktx)
 }

core-ui/src/main/java/com/google/samples/apps/nowinandroid/core/ui/JankStatsExtensions.kt

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.samples.apps.nowinandroid.core.ui
+
+import androidx.compose.foundation.gestures.ScrollableState
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.DisposableEffectResult
+import androidx.compose.runtime.DisposableEffectScope
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.snapshotFlow
+import androidx.compose.ui.platform.LocalView
+import androidx.metrics.performance.PerformanceMetricsState
+import androidx.metrics.performance.PerformanceMetricsState.MetricsStateHolder
+import kotlinx.coroutines.CoroutineScope
+
+/**
+ * Retrieves [PerformanceMetricsState.MetricsStateHolder] from current [LocalView] and
+ * remembers it until the View changes.
+ * @see PerformanceMetricsState.getForHierarchy
+ */
+@Composable
+fun rememberMetricsStateHolder(): MetricsStateHolder {
+    val localView = LocalView.current
+
+    return remember(localView) {
+        PerformanceMetricsState.getForHierarchy(localView)
+    }
+}
+
+/**
+ * Convenience function to work with [PerformanceMetricsState] state. The side effect is
+ * re-launched if any of the [keys] value is not equal to the previous composition.
+ * @see JankMetricDisposableEffect if you need to work with DisposableEffect to cleanup added state.
+ */
+@Composable
+fun JankMetricEffect(
+    vararg keys: Any?,
+    reportMetric: suspend CoroutineScope.(state: MetricsStateHolder) -> Unit
+) {
+    val metrics = rememberMetricsStateHolder()
+    LaunchedEffect(metrics, *keys) {
+        reportMetric(metrics)
+    }
+}
+
+/**
+ * Convenience function to work with [PerformanceMetricsState] state that needs to be cleaned up.
+ * The side effect is re-launched if any of the [keys] value is not equal to the previous composition.
+ */
+@Composable
+fun JankMetricDisposableEffect(
+    vararg keys: Any?,
+    reportMetric: DisposableEffectScope.(state: MetricsStateHolder) -> DisposableEffectResult
+) {
+    val metrics = rememberMetricsStateHolder()
+    DisposableEffect(metrics, *keys) {
+        reportMetric(this, metrics)
+    }
+}
+
+@Composable
+fun TrackScrollJank(scrollableState: ScrollableState, stateName: String) {
+    JankMetricEffect(scrollableState) { metricsHolder ->
+        snapshotFlow { scrollableState.isScrollInProgress }.collect { isScrollInProgress ->
+            metricsHolder.state?.apply {
+                if (isScrollInProgress) {
+                    addState(stateName, "Scrolling=true")
+                } else {
+                    removeState(stateName)
+                }
+            }
+        }
+    }
+}

feature-foryou/src/main/java/com/google/samples/apps/nowinandroid/feature/foryou/AuthorsCarousel.kt

@@ -30,6 +30,7 @@ import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.sizeIn
 import androidx.compose.foundation.lazy.LazyRow
 import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.foundation.selection.toggleable
 import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material.ripple.rememberRipple
@@ -43,6 +44,7 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
 import androidx.compose.ui.layout.ContentScale
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.semantics.Role
 import androidx.compose.ui.semantics.semantics
@@ -57,6 +59,7 @@ import com.google.samples.apps.nowinandroid.core.designsystem.icon.NiaIcons
 import com.google.samples.apps.nowinandroid.core.designsystem.theme.NiaTheme
 import com.google.samples.apps.nowinandroid.core.model.data.Author
 import com.google.samples.apps.nowinandroid.core.model.data.FollowableAuthor
+import com.google.samples.apps.nowinandroid.core.ui.TrackScrollJank
 
 @Composable
 fun AuthorsCarousel(
@@ -64,10 +67,15 @@ fun AuthorsCarousel(
     onAuthorClick: (String, Boolean) -> Unit,
     modifier: Modifier = Modifier
 ) {
+    val lazyListState = rememberLazyListState()
+    val tag = "forYou:authors"
+    TrackScrollJank(scrollableState = lazyListState, stateName = tag)
+
     LazyRow(
-        modifier = modifier,
+        modifier = modifier.testTag(tag),
         contentPadding = PaddingValues(24.dp),
-        horizontalArrangement = Arrangement.spacedBy(24.dp)
+        horizontalArrangement = Arrangement.spacedBy(24.dp),
+        state = lazyListState
     ) {
         items(items = authors, key = { item -> item.author.id }) { followableAuthor ->
             AuthorItem(

feature-foryou/src/main/java/com/google/samples/apps/nowinandroid/feature/foryou/ForYouScreen.kt

@@ -16,6 +16,7 @@
 
 package com.google.samples.apps.nowinandroid.feature.foryou
 
+import android.app.Activity
 import android.content.Intent
 import android.net.Uri
 import androidx.annotation.IntRange
@@ -45,7 +46,9 @@ import androidx.compose.foundation.lazy.LazyListScope
 import androidx.compose.foundation.lazy.grid.GridCells
 import androidx.compose.foundation.lazy.grid.LazyHorizontalGrid
 import androidx.compose.foundation.lazy.grid.items
+import androidx.compose.foundation.lazy.grid.rememberLazyGridState
 import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.foundation.shape.CornerSize
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.ExperimentalMaterial3Api
@@ -59,12 +62,15 @@ import androidx.compose.material3.windowsizeclass.ExperimentalMaterial3WindowSiz
 import androidx.compose.material3.windowsizeclass.WindowSizeClass
 import androidx.compose.material3.windowsizeclass.WindowWidthSizeClass
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.platform.LocalView
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
@@ -73,7 +79,9 @@ import androidx.compose.ui.unit.DpSize
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.max
 import androidx.compose.ui.unit.sp
+import androidx.compose.ui.util.trace
 import androidx.core.content.ContextCompat
+import androidx.core.view.doOnPreDraw
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.ExperimentalLifecycleComposeApi
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
@@ -92,6 +100,7 @@ import com.google.samples.apps.nowinandroid.core.model.data.previewAuthors
 import com.google.samples.apps.nowinandroid.core.model.data.previewNewsResources
 import com.google.samples.apps.nowinandroid.core.model.data.previewTopics
 import com.google.samples.apps.nowinandroid.core.ui.NewsResourceCardExpanded
+import com.google.samples.apps.nowinandroid.core.ui.TrackScrollJank
 import kotlin.math.floor
 
 @OptIn(ExperimentalLifecycleComposeApi::class)
@@ -134,11 +143,11 @@ fun ForYouScreen(
                     titleRes = R.string.top_app_bar_title,
                     navigationIcon = NiaIcons.Search,
                     navigationIconContentDescription = stringResource(
-                        id = R.string.top_app_bar_navigation_button_content_desc
+                        id = R.string.for_you_top_app_bar_action_search
                     ),
                     actionIcon = NiaIcons.AccountCircle,
                     actionIconContentDescription = stringResource(
-                        id = R.string.top_app_bar_navigation_button_content_desc
+                        id = R.string.for_you_top_app_bar_action_my_account
                     ),
                     colors = TopAppBarDefaults.centerAlignedTopAppBarColors(
                         containerColor = Color.Transparent
@@ -163,8 +172,37 @@ fun ForYouScreen(
                     else -> floor(maxWidth / 300.dp).toInt().coerceAtLeast(1)
                 }
 
+                // Workaround to call Activity.reportFullyDrawn from Jetpack Compose.
+                // This code should be called when the UI is ready for use
+                // and relates to Time To Full Display.
+                val interestsLoaded =
+                    interestsSelectionState !is ForYouInterestsSelectionUiState.Loading
+                val feedLoaded = feedState !is ForYouFeedUiState.Loading
+
+                if (interestsLoaded && feedLoaded) {
+                    val localView = LocalView.current
+                    // We use Unit to call reportFullyDrawn only on the first recomposition,
+                    // however it will be called again if this composable goes out of scope.
+                    // Activity.reportFullyDrawn() has its own check for this
+                    // and is safe to call multiple times though.
+                    LaunchedEffect(Unit) {
+                        // We're leveraging the fact, that the current view is directly set as content of Activity.
+                        val activity = localView.context as? Activity ?: return@LaunchedEffect
+                        // To be sure not to call in the middle of a frame draw.
+                        localView.doOnPreDraw { activity.reportFullyDrawn() }
+                    }
+                }
+
+                val tag = "forYou:feed"
+
+                val lazyListState = rememberLazyListState()
+                TrackScrollJank(scrollableState = lazyListState, stateName = tag)
+
                 LazyColumn(
-                    modifier = Modifier.fillMaxSize(),
+                    modifier = Modifier
+                        .fillMaxSize()
+                        .testTag(tag),
+                    state = lazyListState,
                 ) {
                     InterestsSelection(
                         interestsSelectionState = interestsSelectionState,
@@ -215,7 +253,8 @@ private fun LazyListScope.InterestsSelection(
                     NiaLoadingWheel(
                         modifier = Modifier
                             .fillMaxWidth()
-                            .wrapContentSize(),
+                            .wrapContentSize()
+                            .testTag("forYou:loading"),
                         contentDesc = stringResource(id = R.string.for_you_loading),
                     )
                 }
@@ -287,8 +326,12 @@ private fun TopicSelection(
     interestsSelectionState: ForYouInterestsSelectionUiState.WithInterestsSelection,
     onTopicCheckedChanged: (String, Boolean) -> Unit,
     modifier: Modifier = Modifier
-) {
+) = trace("TopicSelection") {
+    val lazyGridState = rememberLazyGridState()
+    TrackScrollJank(scrollableState = lazyGridState, stateName = "forYou:TopicSelection")
+
     LazyHorizontalGrid(
+        state = lazyGridState,
         rows = GridCells.Fixed(3),
         horizontalArrangement = Arrangement.spacedBy(12.dp),
         verticalArrangement = Arrangement.spacedBy(12.dp),
@@ -326,7 +369,7 @@ private fun SingleTopicButton(
     imageUrl: String,
     isSelected: Boolean,
     onClick: (String, Boolean) -> Unit
-) {
+) = trace("SingleTopicButton") {
     Surface(
         modifier = Modifier
             .width(312.dp)

feature-foryou/src/main/res/values/strings.xml

@@ -24,8 +24,8 @@
     <string name="onboarding_guidance_title">What are you interested in?</string>
     <string name="onboarding_guidance_subtitle">Updates from topics you follow will appear here. Follow some things to get started.</string>
     <string name="top_app_bar_title">Now in Android</string>
-    <string name="top_app_bar_action_button_content_desc">My account</string>
+    <string name="for_you_top_app_bar_action_my_account">My account</string>
-    <string name="top_app_bar_navigation_button_content_desc">Search</string>
+    <string name="for_you_top_app_bar_action_search">Search</string>
 
     <!-- Authors-->
     <string name="following">You are following</string>

feature-interests/src/main/java/com/google/samples/apps/nowinandroid/feature/interests/InterestsScreen.kt

@@ -44,6 +44,7 @@ import com.google.samples.apps.nowinandroid.core.model.data.FollowableAuthor
 import com.google.samples.apps.nowinandroid.core.model.data.FollowableTopic
 import com.google.samples.apps.nowinandroid.core.model.data.previewAuthors
 import com.google.samples.apps.nowinandroid.core.model.data.previewTopics
+import com.google.samples.apps.nowinandroid.core.ui.JankMetricDisposableEffect
 
 @OptIn(ExperimentalLifecycleComposeApi::class)
 @Composable
@@ -66,6 +67,14 @@ fun InterestsRoute(
         switchTab = viewModel::switchTab,
         modifier = modifier
     )
+
+    JankMetricDisposableEffect(tabState) { metricsHolder ->
+        metricsHolder.state?.addState("Interests:TabState", "currentIndex:${tabState.currentIndex}")
+
+        onDispose {
+            metricsHolder.state?.removeState("Interests:TabState")
+        }
+    }
 }
 
 @Composable
@@ -89,11 +98,11 @@ fun InterestsScreen(
             titleRes = R.string.interests,
             navigationIcon = NiaIcons.Search,
             navigationIconContentDescription = stringResource(
-                id = R.string.top_app_bar_navigation_button_content_desc
+                id = R.string.interests_top_app_bar_action_seearch
             ),
             actionIcon = NiaIcons.MoreVert,
             actionIconContentDescription = stringResource(
-                id = R.string.top_app_bar_navigation_button_content_desc
+                id = R.string.interests_top_app_bar_action_menu
             ),
             colors = TopAppBarDefaults.centerAlignedTopAppBarColors(
                 containerColor = Color.Transparent

feature-interests/src/main/java/com/google/samples/apps/nowinandroid/feature/interests/TabContent.kt

@@ -27,6 +27,7 @@ import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.unit.dp
 import com.google.samples.apps.nowinandroid.core.model.data.FollowableAuthor
 import com.google.samples.apps.nowinandroid.core.model.data.FollowableTopic
@@ -39,7 +40,9 @@ fun TopicsTabContent(
     modifier: Modifier = Modifier
 ) {
     LazyColumn(
-        modifier = modifier.padding(horizontal = 16.dp),
+        modifier = modifier
+            .padding(horizontal = 16.dp)
+            .testTag("interests:topics"),
         contentPadding = PaddingValues(top = 8.dp)
     ) {
         topics.forEach { followableTopic ->
@@ -69,7 +72,9 @@ fun AuthorsTabContent(
     modifier: Modifier = Modifier
 ) {
     LazyColumn(
-        modifier = modifier.padding(horizontal = 16.dp),
+        modifier = modifier
+            .padding(horizontal = 16.dp)
+            .testTag("interests:people"),
         contentPadding = PaddingValues(top = 8.dp)
     ) {
         authors.forEach { followableAuthor ->

feature-interests/src/main/res/values/strings.xml

@@ -22,6 +22,6 @@
     <string name="interests_empty_header">"No available data"</string>
     <string name="interests_card_follow_button_content_desc">Follow interest button</string>
     <string name="interests_card_unfollow_button_content_desc">Unfollow interest button</string>
-    <string name="top_app_bar_action_button_content_desc">Menu</string>
+    <string name="interests_top_app_bar_action_menu">Menu</string>
-    <string name="top_app_bar_navigation_button_content_desc">Search</string>
+    <string name="interests_top_app_bar_action_seearch">Search</string>
 </resources>

feature-topic/src/androidTest/java/com/google/samples/apps/nowinandroid/feature/topic/TopicScreenTest.kt

@@ -17,9 +17,13 @@
 package com.google.samples.apps.nowinandroid.feature.topic
 
 import androidx.activity.ComponentActivity
+import androidx.compose.ui.test.hasScrollToNodeAction
+import androidx.compose.ui.test.hasText
 import androidx.compose.ui.test.junit4.createAndroidComposeRule
+import androidx.compose.ui.test.onFirst
 import androidx.compose.ui.test.onNodeWithContentDescription
 import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performScrollToNode
 import com.google.samples.apps.nowinandroid.core.model.data.FollowableTopic
 import com.google.samples.apps.nowinandroid.core.model.data.NewsResource
 import com.google.samples.apps.nowinandroid.core.model.data.NewsResourceType.Video
@@ -115,10 +119,11 @@ class TopicScreenTest {
             )
         }
 
-        // First news title shown
+        // Scroll to first news title if available
         composeTestRule
-            .onNodeWithText(sampleNewsResources.first().title)
+            .onAllNodes(hasScrollToNodeAction())
-            .assertExists()
+            .onFirst()
+            .performScrollToNode(hasText(sampleNewsResources.first().title))
     }
 }
 

gradle/libs.versions.toml

@@ -5,6 +5,7 @@ androidGradlePlugin = "7.2.1"
 androidxActivity = "1.4.0"
 androidxAppCompat = "1.4.2"
 androidxCompose = "1.2.0-rc02"
+androidxComposeCompiler = "1.2.0"
 androidxComposeMaterial3 = "1.0.0-alpha13"
 androidxCore = "1.8.0"
 androidxCustomView = "1.0.0-rc01"
@@ -13,13 +14,15 @@ androidxEspresso = "3.4.0"
 androidxHiltNavigationCompose = "1.0.0"
 androidxLifecycle = "2.6.0-alpha01"
 androidxMacroBenchmark = "1.1.0"
-androidxNavigation = "2.4.2"
+androidxNavigation = "2.5.0"
+androidxMetrics = "1.0.0-alpha01"
 androidxProfileinstaller = "1.2.0-rc01"
 androidxSavedState = "1.1.0"
 androidxStartup = "1.1.1"
 androidxWindowManager = "1.0.0"
 androidxTest = "1.4.0"
 androidxTestExt = "1.1.3"
+androidxTracing = "1.1.0"
 androidxUiAutomator = "2.2.0"
 androidxWork = "2.7.1"
 coil = "2.1.0"
@@ -27,17 +30,17 @@ hilt = "2.42"
 hiltExt = "1.0.0"
 jacoco = "0.8.7"
 junit4 = "4.13.2"
-kotlin = "1.6.21"
+kotlin = "1.7.0"
 kotlinxCoroutines = "1.6.3"
 kotlinxDatetime = "0.3.3"
 kotlinxSerializationJson = "1.3.3"
-ksp = "1.6.21-1.0.5"
+ksp = "1.7.0-1.0.6"
 ktlint = "0.43.0"
 lint = "30.2.1"
 material3 = "1.6.1"
 okhttp = "4.10.0"
 protobuf = "3.21.1"
-protobufPlugin = "0.8.18"
+protobufPlugin = "0.8.19"
 retrofit = "2.9.0"
 retrofitKotlinxSerializationJson = "0.8.0"
 room = "2.4.2"
@@ -71,6 +74,7 @@ androidx-dataStore-preferences = { group = "androidx.datastore", name = "datasto
 androidx-hilt-navigation-compose = { group = "androidx.hilt", name = "hilt-navigation-compose", version.ref = "androidxHiltNavigationCompose" }
 androidx-lifecycle-runtimeCompose = { group = "androidx.lifecycle", name = "lifecycle-runtime-compose", version.ref = "androidxLifecycle" }
 androidx-lifecycle-viewModelCompose = { group = "androidx.lifecycle", name = "lifecycle-viewmodel-compose", version.ref = "androidxLifecycle" }
+androidx-metrics = { group = "androidx.metrics", name = "metrics-performance", version.ref = "androidxMetrics" }
 androidx-navigation-compose = { group = "androidx.navigation", name = "navigation-compose", version.ref = "androidxNavigation" }
 androidx-profileinstaller = { group = "androidx.profileinstaller", name = "profileinstaller", version.ref = "androidxProfileinstaller" }
 androidx-savedstate-ktx = { group = "androidx.savedstate", name = "savedstate-ktx", version.ref= "androidxSavedState"}
@@ -82,6 +86,7 @@ androidx-test-espresso-core = { group = "androidx.test.espresso", name = "espres
 androidx-test-runner = { group = "androidx.test", name = "runner", version.ref = "androidxTest" }
 androidx-test-rules = { group = "androidx.test", name = "rules", version.ref = "androidxTest" }
 androidx-test-uiautomator = { group = "androidx.test.uiautomator", name = "uiautomator", version.ref = "androidxUiAutomator" }
+androidx-tracing-ktx = {group = "androidx.tracing", name="tracing-ktx", version.ref = "androidxTracing" }
 androidx-work-ktx = { group = "androidx.work", name = "work-runtime-ktx", version.ref = "androidxWork" }
 androidx-work-testing = { group = "androidx.work", name = "work-testing", version.ref = "androidxWork" }
 coil-kt = { group = "io.coil-kt", name = "coil", version.ref = "coil"}

sync/build.gradle.kts

@@ -35,6 +35,7 @@ dependencies {
 
     implementation(libs.kotlinx.coroutines.android)
 
+    implementation(libs.androidx.tracing.ktx)
     implementation(libs.androidx.startup)
     implementation(libs.androidx.work.ktx)
     implementation(libs.hilt.ext.work)

sync/src/main/java/com/google/samples/apps/nowinandroid/sync/workers/SyncWorker.kt

@@ -18,6 +18,7 @@ package com.google.samples.apps.nowinandroid.sync.workers
 
 import android.content.Context
 import androidx.hilt.work.HiltWorker
+import androidx.tracing.traceAsync
 import androidx.work.CoroutineWorker
 import androidx.work.ForegroundInfo
 import androidx.work.OneTimeWorkRequestBuilder
@@ -59,15 +60,17 @@ class SyncWorker @AssistedInject constructor(
         appContext.syncForegroundInfo()
 
     override suspend fun doWork(): Result = withContext(ioDispatcher) {
-        // First sync the repositories in parallel
+        traceAsync("Sync", 0) {
-        val syncedSuccessfully = awaitAll(
+            // First sync the repositories in parallel
-            async { topicRepository.sync() },
+            val syncedSuccessfully = awaitAll(
-            async { authorsRepository.sync() },
+                async { topicRepository.sync() },
-            async { newsRepository.sync() },
+                async { authorsRepository.sync() },
-        ).all { it }
+                async { newsRepository.sync() },
+            ).all { it }
 
-        if (syncedSuccessfully) Result.success()
+            if (syncedSuccessfully) Result.success()
-        else Result.retry()
+            else Result.retry()
+        }
     }
 
     override suspend fun getChangeListVersions(): ChangeListVersions =