Even better names

Change-Id: Ia699c3ce8fd1ce7a6e406b00c81dc196b487ed65

core/designsystem/src/main/java/com/google/samples/apps/nowinandroid/core/designsystem/component/scrollbar/AppScrollbars.kt

@@ -23,6 +23,7 @@ import androidx.compose.foundation.background
 import androidx.compose.foundation.gestures.Orientation
 import androidx.compose.foundation.gestures.Orientation.Horizontal
 import androidx.compose.foundation.gestures.Orientation.Vertical
+import androidx.compose.foundation.gestures.ScrollableState
 import androidx.compose.foundation.interaction.InteractionSource
 import androidx.compose.foundation.interaction.MutableInteractionSource
 import androidx.compose.foundation.interaction.collectIsDraggedAsState
@@ -56,18 +57,15 @@ private const val INACTIVE_TO_DORMANT_COOL_DOWN = 2_000L
  * Its thumb disappears when the scrolling container is dormant.
  * @param modifier a [Modifier] for the [Scrollbar]
  * @param state the driving state for the [Scrollbar]
- * @param scrollInProgress a flag indicating if the scrolling container for the scrollbar is
- * currently scrolling
  * @param orientation the orientation of the scrollbar
- * @param onThumbMoved the fast scroll implementation
+ * @param onThumbDisplaced the fast scroll implementation
  */
 @Composable
-fun FastScrollbar(
+fun ScrollableState.FastScrollbar(
     modifier: Modifier = Modifier,
     state: ScrollbarState,
-    scrollInProgress: Boolean,
     orientation: Orientation,
-    onThumbMoved: (Float) -> Unit,
+    onThumbDisplaced: (Float) -> Unit,
 ) {
     val interactionSource = remember { MutableInteractionSource() }
     Scrollbar(
@@ -77,12 +75,11 @@ fun FastScrollbar(
         state = state,
         thumb = {
             FastScrollbarThumb(
-                scrollInProgress = scrollInProgress,
                 interactionSource = interactionSource,
                 orientation = orientation,
             )
         },
-        onThumbDisplaced = onThumbMoved,
+        onThumbDisplaced = onThumbDisplaced,
     )
 }
 
@@ -91,15 +88,12 @@ fun FastScrollbar(
  * Its thumb disappears when the scrolling container is dormant.
  * @param modifier a [Modifier] for the [Scrollbar]
  * @param state the driving state for the [Scrollbar]
- * @param scrollInProgress a flag indicating if the scrolling container for the scrollbar is
- * currently scrolling
  * @param orientation the orientation of the scrollbar
  */
 @Composable
-fun DecorativeScrollbar(
+fun ScrollableState.DecorativeScrollbar(
     modifier: Modifier = Modifier,
     state: ScrollbarState,
-    scrollInProgress: Boolean,
     orientation: Orientation,
 ) {
     val interactionSource = remember { MutableInteractionSource() }
@@ -111,7 +105,6 @@ fun DecorativeScrollbar(
         thumb = {
             DecorativeScrollbarThumb(
                 interactionSource = interactionSource,
-                scrollInProgress = scrollInProgress,
                 orientation = orientation,
             )
         },
@@ -122,8 +115,7 @@ fun DecorativeScrollbar(
  * A scrollbar thumb that is intended to also be a touch target for fast scrolling.
  */
 @Composable
-private fun FastScrollbarThumb(
-    scrollInProgress: Boolean,
+private fun ScrollableState.FastScrollbarThumb(
     interactionSource: InteractionSource,
     orientation: Orientation,
 ) {
@@ -137,7 +129,6 @@ private fun FastScrollbarThumb(
             }
             .background(
                 color = scrollbarThumbColor(
-                    scrollInProgress = scrollInProgress,
                     interactionSource = interactionSource,
                 ),
                 shape = RoundedCornerShape(16.dp),
@@ -149,8 +140,7 @@ private fun FastScrollbarThumb(
  * A decorative scrollbar thumb for communicating a user's position in a list solely.
  */
 @Composable
-private fun DecorativeScrollbarThumb(
-    scrollInProgress: Boolean,
+private fun ScrollableState.DecorativeScrollbarThumb(
     interactionSource: InteractionSource,
     orientation: Orientation,
 ) {
@@ -164,7 +154,6 @@ private fun DecorativeScrollbarThumb(
             }
             .background(
                 color = scrollbarThumbColor(
-                    scrollInProgress = scrollInProgress,
                     interactionSource = interactionSource,
                 ),
                 shape = RoundedCornerShape(16.dp),
@@ -174,19 +163,18 @@ private fun DecorativeScrollbarThumb(
 
 /**
  * The color of the scrollbar thumb as a function of its interaction state.
- * @param scrollInProgress if the scrolling container is currently scrolling
  * @param interactionSource source of interactions in the scrolling container
  */
 @Composable
-private fun scrollbarThumbColor(
-    scrollInProgress: Boolean,
+private fun ScrollableState.scrollbarThumbColor(
     interactionSource: InteractionSource,
 ): Color {
     var state by remember { mutableStateOf(Dormant) }
     val pressed by interactionSource.collectIsPressedAsState()
     val hovered by interactionSource.collectIsHoveredAsState()
     val dragged by interactionSource.collectIsDraggedAsState()
-    val active = pressed || hovered || dragged || scrollInProgress
+    val active = (canScrollForward || canScrollForward) &&
+        (pressed || hovered || dragged || isScrollInProgress)
 
     val color by animateColorAsState(
         targetValue = when (state) {
@@ -202,7 +190,7 @@ private fun scrollbarThumbColor(
     LaunchedEffect(active) {
         when (active) {
             true -> state = Active
-            false -> {
+            false -> if (state == Active) {
                 state = Inactive
                 delay(INACTIVE_TO_DORMANT_COOL_DOWN)
                 state = Dormant

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

@@ -27,36 +27,36 @@ import androidx.compose.runtime.rememberUpdatedState
 import androidx.compose.runtime.setValue
 
 /**
- * Remembers a function to react to [Scrollbar] thumb position movements for a [LazyListState]
+ * Remembers a function to react to [Scrollbar] thumb position displacements for a [LazyListState]
  * @param itemsAvailable the amount of items in the list.
  */
 @Composable
-fun LazyListState.rememberThumbInteractions(
+fun LazyListState.rememberFastScroller(
     itemsAvailable: Int,
-): (Float) -> Unit = rememberThumbInteractions(
+): (Float) -> Unit = rememberFastScroller(
     itemsAvailable = itemsAvailable,
     scroll = ::scrollToItem,
 )
 
 /**
- * Remembers a function to react to [Scrollbar] thumb position movements for a [LazyGridState]
+ * Remembers a function to react to [Scrollbar] thumb position displacements for a [LazyGridState]
  * @param itemsAvailable the amount of items in the grid.
  */
 @Composable
-fun LazyGridState.rememberThumbInteractions(
+fun LazyGridState.rememberFastScroller(
     itemsAvailable: Int,
-): (Float) -> Unit = rememberThumbInteractions(
+): (Float) -> Unit = rememberFastScroller(
     itemsAvailable = itemsAvailable,
     scroll = ::scrollToItem,
 )
 
 /**
- * Generic function to react to [Scrollbar] thumb interactions in a lazy layout.
+ * 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.
  * @param scroll a function to be invoked when an index has been identified to scroll to.
  */
 @Composable
-private inline fun rememberThumbInteractions(
+private inline fun rememberFastScroller(
     itemsAvailable: Int,
     crossinline scroll: suspend (index: Int) -> Unit,
 ): (Float) -> Unit {
@@ -69,6 +69,6 @@ private inline fun rememberThumbInteractions(
         scroll(indexToFind)
     }
     return remember {
-        { percentage = it }
+        { newPercentage -> percentage = newPercentage }
     }
 }

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

@@ -20,6 +20,7 @@ import androidx.annotation.VisibleForTesting
 import androidx.compose.foundation.Image
 import androidx.compose.foundation.gestures.Orientation
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.Spacer
@@ -62,7 +63,7 @@ import androidx.lifecycle.LifecycleEventObserver
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaLoadingWheel
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.FastScrollbar
-import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberThumbInteractions
+import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberFastScroller
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.scrollbarState
 import com.google.samples.apps.nowinandroid.core.designsystem.theme.LocalTintTheme
 import com.google.samples.apps.nowinandroid.core.designsystem.theme.NiaTheme
@@ -121,11 +122,8 @@ internal fun BookmarksScreen(
             if (snackBarResult) {
 
                 undoBookmarkRemoval()
-                }
-
-                else  {
+            } else {
                 clearUndoState()
-
             }
         }
     }
@@ -154,7 +152,6 @@ internal fun BookmarksScreen(
             )
         } else {
             EmptyState(modifier)
-
         }
     }
 
@@ -213,7 +210,7 @@ private fun BookmarksGrid(
         val scrollbarState = scrollableState.scrollbarState(
             itemsAvailable = itemsAvailable,
         )
-        FastScrollbar(
+        scrollableState.FastScrollbar(
             modifier = Modifier
                 .fillMaxHeight()
                 .windowInsetsPadding(WindowInsets.systemBars)
@@ -221,8 +218,7 @@ private fun BookmarksGrid(
                 .align(Alignment.CenterEnd),
             state = scrollbarState,
             orientation = Orientation.Vertical,
-            scrollInProgress = scrollableState.isScrollInProgress,
-            onThumbMoved = scrollableState.rememberThumbInteractions(
+            onThumbDisplaced = scrollableState.rememberFastScroller(
                 itemsAvailable = itemsAvailable,
             ),
         )

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

@@ -93,7 +93,7 @@ import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaIconT
 import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaOverlayLoadingWheel
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.DecorativeScrollbar
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.FastScrollbar
-import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberThumbInteractions
+import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberFastScroller
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.scrollbarState
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.NiaIcons
 import com.google.samples.apps.nowinandroid.core.designsystem.theme.NiaTheme
@@ -230,7 +230,7 @@ internal fun ForYouScreen(
                 )
             }
         }
-        FastScrollbar(
+        state.FastScrollbar(
             modifier = Modifier
                 .fillMaxHeight()
                 .windowInsetsPadding(WindowInsets.systemBars)
@@ -238,8 +238,7 @@ internal fun ForYouScreen(
                 .align(Alignment.CenterEnd),
             state = scrollbarState,
             orientation = Orientation.Vertical,
-            scrollInProgress = state.isScrollInProgress,
-            onThumbMoved = state.rememberThumbInteractions(
+            onThumbDisplaced = state.rememberFastScroller(
                 itemsAvailable = itemsAvailable,
             ),
         )
@@ -365,14 +364,13 @@ private fun TopicSelection(
                 )
             }
         }
-        DecorativeScrollbar(
+        lazyGridState.DecorativeScrollbar(
             modifier = Modifier
                 .fillMaxWidth()
                 .padding(horizontal = 12.dp)
                 .align(Alignment.BottomStart),
             state = lazyGridState.scrollbarState(itemsAvailable = onboardingUiState.topics.size),
             orientation = Orientation.Horizontal,
-            scrollInProgress = lazyGridState.isScrollInProgress,
         )
     }
 }

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

@@ -36,7 +36,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.unit.dp
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.FastScrollbar
-import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberThumbInteractions
+import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberFastScroller
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.scrollbarState
 import com.google.samples.apps.nowinandroid.core.model.data.FollowableTopic
 
@@ -83,7 +83,7 @@ fun TopicsTabContent(
         val scrollbarState = scrollableState.scrollbarState(
             itemsAvailable = topics.size,
         )
-        FastScrollbar(
+        scrollableState.FastScrollbar(
             modifier = Modifier
                 .fillMaxHeight()
                 .windowInsetsPadding(WindowInsets.systemBars)
@@ -91,8 +91,7 @@ fun TopicsTabContent(
                 .align(Alignment.CenterEnd),
             state = scrollbarState,
             orientation = Orientation.Vertical,
-            scrollInProgress = scrollableState.isScrollInProgress,
-            onThumbMoved = scrollableState.rememberThumbInteractions(
+            onThumbDisplaced = scrollableState.rememberFastScroller(
                 itemsAvailable = topics.size,
             ),
         )

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

@@ -17,17 +17,22 @@
 package com.google.samples.apps.nowinandroid.feature.search
 
 import androidx.compose.foundation.clickable
+import androidx.compose.foundation.gestures.Orientation
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.WindowInsets
+import androidx.compose.foundation.layout.fillMaxHeight
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.safeDrawing
+import androidx.compose.foundation.layout.systemBars
 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
@@ -75,12 +80,17 @@ import androidx.compose.ui.tooling.preview.PreviewParameter
 import androidx.compose.ui.unit.dp
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.FastScrollbar
+import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberFastScroller
+import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.scrollbarState
 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.FollowableTopic
 import com.google.samples.apps.nowinandroid.core.model.data.UserNewsResource
 import com.google.samples.apps.nowinandroid.core.ui.DevicePreviews
 import com.google.samples.apps.nowinandroid.core.ui.NewsFeedUiState
+import com.google.samples.apps.nowinandroid.core.ui.NewsFeedUiState.Loading
+import com.google.samples.apps.nowinandroid.core.ui.NewsFeedUiState.Success
 import com.google.samples.apps.nowinandroid.core.ui.R.string
 import com.google.samples.apps.nowinandroid.core.ui.TrackScreenViewEvent
 import com.google.samples.apps.nowinandroid.core.ui.newsFeed
@@ -289,6 +299,10 @@ private fun SearchResultBody(
     searchQuery: String = "",
 ) {
     val state = rememberLazyGridState()
+    Box(
+        modifier = Modifier
+            .fillMaxSize(),
+    ) {
         LazyVerticalGrid(
             columns = Adaptive(300.dp),
             contentPadding = PaddingValues(16.dp),
@@ -355,7 +369,7 @@ private fun SearchResultBody(
                 }
 
                 newsFeed(
-                feedState = NewsFeedUiState.Success(feed = newsResources),
+                    feedState = Success(feed = newsResources),
                     onNewsResourcesCheckedChanged = onNewsResourcesCheckedChanged,
                     onNewsResourceViewed = onNewsResourceViewed,
                     onTopicClick = onTopicClick,
@@ -365,6 +379,23 @@ private fun SearchResultBody(
                 )
             }
         }
+        val itemsAvailable = topics.size + newsResources.size
+        val scrollbarState = state.scrollbarState(
+            itemsAvailable = itemsAvailable,
+        )
+        state.FastScrollbar(
+            modifier = Modifier
+                .fillMaxHeight()
+                .windowInsetsPadding(WindowInsets.systemBars)
+                .padding(horizontal = 2.dp)
+                .align(Alignment.CenterEnd),
+            state = scrollbarState,
+            orientation = Orientation.Vertical,
+            onThumbDisplaced = state.rememberFastScroller(
+                itemsAvailable = itemsAvailable,
+            ),
+        )
+    }
 }
 
 @Composable

feature/topic/src/main/java/com/google/samples/apps/nowinandroid/feature/topic/TopicScreen.kt

@@ -55,7 +55,7 @@ import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaBackg
 import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaFilterChip
 import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaLoadingWheel
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.FastScrollbar
-import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberThumbInteractions
+import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.rememberFastScroller
 import com.google.samples.apps.nowinandroid.core.designsystem.component.scrollbar.scrollbarState
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.NiaIcons
 import com.google.samples.apps.nowinandroid.core.designsystem.theme.NiaTheme
@@ -151,7 +151,7 @@ internal fun TopicScreen(
         val scrollbarState = state.scrollbarState(
             itemsAvailable = itemsAvailable,
         )
-        FastScrollbar(
+        state.FastScrollbar(
             modifier = Modifier
                 .fillMaxHeight()
                 .windowInsetsPadding(WindowInsets.systemBars)
@@ -159,8 +159,7 @@ internal fun TopicScreen(
                 .align(Alignment.CenterEnd),
             state = scrollbarState,
             orientation = Orientation.Vertical,
-            scrollInProgress = state.isScrollInProgress,
-            onThumbMoved = state.rememberThumbInteractions(
+            onThumbDisplaced = state.rememberFastScroller(
                 itemsAvailable = itemsAvailable,
             ),
         )