Use lazy vertical staggered grid in feed to maximize space utilization

Change-Id: I66fff57bd0f11f5f73e7e5c9b5c51b0fa6a76926

core/designsystem/src/main/kotlin/com/google/samples/apps/nowinandroid/core/designsystem/component/scrollbar/ScrollbarExt.kt

@@ -21,6 +21,8 @@ import androidx.compose.foundation.lazy.LazyListItemInfo
 import androidx.compose.foundation.lazy.LazyListState
 import androidx.compose.foundation.lazy.grid.LazyGridItemInfo
 import androidx.compose.foundation.lazy.grid.LazyGridState
+import androidx.compose.foundation.lazy.staggeredgrid.LazyStaggeredGridItemInfo
+import androidx.compose.foundation.lazy.staggeredgrid.LazyStaggeredGridState
 import androidx.compose.runtime.Composable
 
 /**
@@ -102,3 +104,40 @@ fun LazyGridState.scrollbarState(
         },
         reverseLayout = { layoutInfo.reverseLayout },
     )
+
+/**
+ * Remembers a [ScrollbarState] driven by the changes in a [LazyStaggeredGridState]
+ *
+ * @param itemsAvailable the total amount of items available to scroll in the staggered grid.
+ * @param itemIndex a lookup function for index of an item in the staggered grid relative
+ * to [itemsAvailable].
+ */
+@Composable
+fun LazyStaggeredGridState.scrollbarState(
+    itemsAvailable: Int,
+    itemIndex: (LazyStaggeredGridItemInfo) -> Int = LazyStaggeredGridItemInfo::index,
+): ScrollbarState =
+    scrollbarState(
+        itemsAvailable = itemsAvailable,
+        visibleItems = { layoutInfo.visibleItemsInfo },
+        firstVisibleItemIndex = { visibleItems ->
+            interpolateFirstItemIndex(
+                visibleItems = visibleItems,
+                itemSize = { layoutInfo.orientation.valueOf(it.size) },
+                offset = { layoutInfo.orientation.valueOf(it.offset) },
+                nextItemOnMainAxis = { first ->
+                    visibleItems.find { it != first && it.lane == first.lane }
+                },
+                itemIndex = itemIndex,
+            )
+        },
+        itemPercentVisible = itemPercentVisible@{ itemInfo ->
+            itemVisibilityPercentage(
+                itemSize = layoutInfo.orientation.valueOf(itemInfo.size),
+                itemStartOffset = layoutInfo.orientation.valueOf(itemInfo.offset),
+                viewportStartOffset = layoutInfo.viewportStartOffset,
+                viewportEndOffset = layoutInfo.viewportEndOffset,
+            )
+        },
+        reverseLayout = { false },
+    )

core/designsystem/src/main/kotlin/com/google/samples/apps/nowinandroid/core/designsystem/component/scrollbar/ThumbExt.kt

@@ -18,6 +18,7 @@ package com.google.samples.apps.nowinandroid.core.designsystem.component.scrollb
 
 import androidx.compose.foundation.lazy.LazyListState
 import androidx.compose.foundation.lazy.grid.LazyGridState
+import androidx.compose.foundation.lazy.staggeredgrid.LazyStaggeredGridState
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
@@ -50,6 +51,19 @@ fun LazyGridState.rememberDraggableScroller(
     scroll = ::scrollToItem,
 )
 
+/**
+ * Remembers a function to react to [Scrollbar] thumb position displacements for a
+ * [LazyStaggeredGridState]
+ * @param itemsAvailable the amount of items in the staggered grid.
+ */
+@Composable
+fun LazyStaggeredGridState.rememberDraggableScroller(
+    itemsAvailable: Int,
+): (Float) -> Unit = rememberDraggableScroller(
+    itemsAvailable = itemsAvailable,
+    scroll = ::scrollToItem,
+)
+
 /**
  * Generic function to react to [Scrollbar] thumb displacements in a lazy layout.
  * @param itemsAvailable the total amount of items available to scroll in the layout.

core/ui/src/main/kotlin/com/google/samples/apps/nowinandroid/core/ui/NewsFeed.kt

@@ -23,10 +23,10 @@ import androidx.browser.customtabs.CustomTabColorSchemeParams
 import androidx.browser.customtabs.CustomTabsIntent
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.lazy.LazyListScope
-import androidx.compose.foundation.lazy.grid.GridCells
+import androidx.compose.foundation.lazy.staggeredgrid.LazyStaggeredGridScope
-import androidx.compose.foundation.lazy.grid.LazyGridScope
+import androidx.compose.foundation.lazy.staggeredgrid.LazyVerticalStaggeredGrid
-import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
+import androidx.compose.foundation.lazy.staggeredgrid.StaggeredGridCells
-import androidx.compose.foundation.lazy.grid.items
+import androidx.compose.foundation.lazy.staggeredgrid.items
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
@@ -47,7 +47,7 @@ import com.google.samples.apps.nowinandroid.core.model.data.UserNewsResource
  * An extension on [LazyListScope] defining a feed with news resources.
  * Depending on the [feedState], this might emit no items.
  */
-fun LazyGridScope.newsFeed(
+fun LazyStaggeredGridScope.newsFeed(
     feedState: NewsFeedUiState,
     onNewsResourcesCheckedChanged: (String, Boolean) -> Unit,
     onNewsResourceViewed: (String) -> Unit,
@@ -129,7 +129,7 @@ sealed interface NewsFeedUiState {
 @Composable
 private fun NewsFeedLoadingPreview() {
     NiaTheme {
-        LazyVerticalGrid(columns = GridCells.Adaptive(300.dp)) {
+        LazyVerticalStaggeredGrid(columns = StaggeredGridCells.Adaptive(300.dp)) {
             newsFeed(
                 feedState = NewsFeedUiState.Loading,
                 onNewsResourcesCheckedChanged = { _, _ -> },
@@ -148,7 +148,7 @@ private fun NewsFeedContentPreview(
     userNewsResources: List<UserNewsResource>,
 ) {
     NiaTheme {
-        LazyVerticalGrid(columns = GridCells.Adaptive(300.dp)) {
+        LazyVerticalStaggeredGrid(columns = StaggeredGridCells.Adaptive(300.dp)) {
             newsFeed(
                 feedState = NewsFeedUiState.Success(userNewsResources),
                 onNewsResourcesCheckedChanged = { _, _ -> },

feature/bookmarks/src/main/kotlin/com/google/samples/apps/nowinandroid/feature/bookmarks/BookmarksScreen.kt

@@ -35,10 +35,10 @@ import androidx.compose.foundation.layout.systemBars
 import androidx.compose.foundation.layout.windowInsetsBottomHeight
 import androidx.compose.foundation.layout.windowInsetsPadding
 import androidx.compose.foundation.layout.wrapContentSize
-import androidx.compose.foundation.lazy.grid.GridCells.Adaptive
+import androidx.compose.foundation.lazy.staggeredgrid.LazyVerticalStaggeredGrid
-import androidx.compose.foundation.lazy.grid.GridItemSpan
+import androidx.compose.foundation.lazy.staggeredgrid.StaggeredGridCells
-import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
+import androidx.compose.foundation.lazy.staggeredgrid.StaggeredGridItemSpan
-import androidx.compose.foundation.lazy.grid.rememberLazyGridState
+import androidx.compose.foundation.lazy.staggeredgrid.rememberLazyStaggeredGridState
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
@@ -175,17 +175,17 @@ private fun BookmarksGrid(
     onTopicClick: (String) -> Unit,
     modifier: Modifier = Modifier,
 ) {
-    val scrollableState = rememberLazyGridState()
+    val scrollableState = rememberLazyStaggeredGridState()
     TrackScrollJank(scrollableState = scrollableState, stateName = "bookmarks:grid")
     Box(
         modifier = modifier
             .fillMaxSize(),
     ) {
-        LazyVerticalGrid(
+        LazyVerticalStaggeredGrid(
-            columns = Adaptive(300.dp),
+            columns = StaggeredGridCells.Adaptive(300.dp),
             contentPadding = PaddingValues(16.dp),
             horizontalArrangement = Arrangement.spacedBy(16.dp),
-            verticalArrangement = Arrangement.spacedBy(24.dp),
+            verticalItemSpacing = 24.dp,
             state = scrollableState,
             modifier = Modifier
                 .fillMaxSize()
@@ -197,7 +197,7 @@ private fun BookmarksGrid(
                 onNewsResourceViewed = onNewsResourceViewed,
                 onTopicClick = onTopicClick,
             )
-            item(span = { GridItemSpan(maxLineSpan) }) {
+            item(span = StaggeredGridItemSpan.FullLine) {
                 Spacer(Modifier.windowInsetsBottomHeight(WindowInsets.safeDrawing))
             }
         }

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

@@ -49,13 +49,14 @@ import androidx.compose.foundation.layout.windowInsetsBottomHeight
 import androidx.compose.foundation.layout.windowInsetsPadding
 import androidx.compose.foundation.lazy.LazyListScope
 import androidx.compose.foundation.lazy.grid.GridCells
-import androidx.compose.foundation.lazy.grid.GridCells.Adaptive
-import androidx.compose.foundation.lazy.grid.GridItemSpan
-import androidx.compose.foundation.lazy.grid.LazyGridScope
 import androidx.compose.foundation.lazy.grid.LazyHorizontalGrid
-import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
 import androidx.compose.foundation.lazy.grid.items
 import androidx.compose.foundation.lazy.grid.rememberLazyGridState
+import androidx.compose.foundation.lazy.staggeredgrid.LazyStaggeredGridScope
+import androidx.compose.foundation.lazy.staggeredgrid.LazyVerticalStaggeredGrid
+import androidx.compose.foundation.lazy.staggeredgrid.StaggeredGridCells
+import androidx.compose.foundation.lazy.staggeredgrid.StaggeredGridItemSpan
+import androidx.compose.foundation.lazy.staggeredgrid.rememberLazyStaggeredGridState
 import androidx.compose.foundation.shape.CornerSize
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.Icon
@@ -153,7 +154,7 @@ internal fun ForYouScreen(
 
     val itemsAvailable = feedItemsSize(feedState, onboardingUiState)
 
-    val state = rememberLazyGridState()
+    val state = rememberLazyStaggeredGridState()
     val scrollbarState = state.scrollbarState(
         itemsAvailable = itemsAvailable,
     )
@@ -163,11 +164,11 @@ internal fun ForYouScreen(
         modifier = modifier
             .fillMaxSize(),
     ) {
-        LazyVerticalGrid(
+        LazyVerticalStaggeredGrid(
-            columns = Adaptive(300.dp),
+            columns = StaggeredGridCells.Adaptive(300.dp),
             contentPadding = PaddingValues(16.dp),
             horizontalArrangement = Arrangement.spacedBy(16.dp),
-            verticalArrangement = Arrangement.spacedBy(24.dp),
+            verticalItemSpacing = 24.dp,
             modifier = Modifier
                 .testTag("forYou:feed"),
             state = state,
@@ -197,7 +198,7 @@ internal fun ForYouScreen(
                 onTopicClick = onTopicClick,
             )
 
-            item(span = { GridItemSpan(maxLineSpan) }, contentType = "bottomSpacing") {
+            item(span = StaggeredGridItemSpan.FullLine, contentType = "bottomSpacing") {
                 Column {
                     Spacer(modifier = Modifier.height(8.dp))
                     // Add space for the content to clear the "offline" snackbar.
@@ -255,7 +256,7 @@ internal fun ForYouScreen(
  * Depending on the [onboardingUiState], this might emit no items.
  *
  */
-private fun LazyGridScope.onboarding(
+private fun LazyStaggeredGridScope.onboarding(
     onboardingUiState: OnboardingUiState,
     onTopicCheckedChanged: (String, Boolean) -> Unit,
     saveFollowedTopics: () -> Unit,
@@ -268,7 +269,7 @@ private fun LazyGridScope.onboarding(
         -> Unit
 
         is OnboardingUiState.Shown -> {
-            item(span = { GridItemSpan(maxLineSpan) }, contentType = "onboarding") {
+            item(span = StaggeredGridItemSpan.FullLine, contentType = "onboarding") {
                 Column(modifier = interestsItemModifier) {
                     Text(
                         text = stringResource(R.string.onboarding_guidance_title),

feature/search/src/main/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchScreen.kt

@@ -35,11 +35,11 @@ import androidx.compose.foundation.layout.windowInsetsBottomHeight
 import androidx.compose.foundation.layout.windowInsetsPadding
 import androidx.compose.foundation.layout.windowInsetsTopHeight
 import androidx.compose.foundation.lazy.LazyColumn
-import androidx.compose.foundation.lazy.grid.GridCells.Adaptive
-import androidx.compose.foundation.lazy.grid.GridItemSpan
-import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
-import androidx.compose.foundation.lazy.grid.rememberLazyGridState
 import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.lazy.staggeredgrid.LazyVerticalStaggeredGrid
+import androidx.compose.foundation.lazy.staggeredgrid.StaggeredGridCells
+import androidx.compose.foundation.lazy.staggeredgrid.StaggeredGridItemSpan
+import androidx.compose.foundation.lazy.staggeredgrid.rememberLazyStaggeredGridState
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.ClickableText
 import androidx.compose.foundation.text.KeyboardActions
@@ -297,16 +297,16 @@ private fun SearchResultBody(
     onTopicClick: (String) -> Unit,
     searchQuery: String = "",
 ) {
-    val state = rememberLazyGridState()
+    val state = rememberLazyStaggeredGridState()
     Box(
         modifier = Modifier
             .fillMaxSize(),
     ) {
-        LazyVerticalGrid(
+        LazyVerticalStaggeredGrid(
-            columns = Adaptive(300.dp),
+            columns = StaggeredGridCells.Adaptive(300.dp),
             contentPadding = PaddingValues(16.dp),
             horizontalArrangement = Arrangement.spacedBy(16.dp),
-            verticalArrangement = Arrangement.spacedBy(24.dp),
+            verticalItemSpacing = 24.dp,
             modifier = Modifier
                 .fillMaxSize()
                 .testTag("search:newsResources"),
@@ -314,9 +314,7 @@ private fun SearchResultBody(
         ) {
             if (topics.isNotEmpty()) {
                 item(
-                    span = {
+                    span = StaggeredGridItemSpan.FullLine,
-                        GridItemSpan(maxLineSpan)
-                    },
                 ) {
                     Text(
                         text = buildAnnotatedString {
@@ -331,9 +329,7 @@ private fun SearchResultBody(
                     val topicId = followableTopic.topic.id
                     item(
                         key = "topic-$topicId", // Append a prefix to distinguish a key for news resources
-                        span = {
+                        span = StaggeredGridItemSpan.FullLine,
-                            GridItemSpan(maxLineSpan)
-                        },
                     ) {
                         InterestsItem(
                             name = followableTopic.topic.name,
@@ -353,9 +349,7 @@ private fun SearchResultBody(
 
             if (newsResources.isNotEmpty()) {
                 item(
-                    span = {
+                    span = StaggeredGridItemSpan.FullLine,
-                        GridItemSpan(maxLineSpan)
-                    },
                 ) {
                     Text(
                         text = buildAnnotatedString {

gradle/libs.versions.toml

@@ -5,7 +5,7 @@ androidGradlePlugin = "8.1.1"
 androidxActivity = "1.8.0-alpha06"
 androidxAppCompat = "1.5.1"
 androidxBrowser = "1.4.0"
-androidxComposeBom = "2023.06.01"
+androidxComposeBom = "2023.09.00"
 androidxComposeCompiler = "1.5.0"
 androidxComposeRuntimeTracing = "1.0.0-alpha03"
 androidxCore = "1.9.0"