UI: lists use Calendula's GroupedRow family pattern

Copy Calendula's GroupedRow (connected surface segments, press-morph corners)
and the circular colour chip into Floret's ui/common, and render the lists with
them: full-width rows, 72dp height, 2dp connect-gap, ListColorChip (pastelised
list colour + checklist glyph). Shared identity across the two apps.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/src/main/java/de/jeanlucmakiola/floret/ui/common/GroupedList.kt

@@ -0,0 +1,116 @@
+package de.jeanlucmakiola.floret.ui.common
+
+import androidx.compose.animation.core.animateDpAsState
+import androidx.compose.foundation.interaction.MutableInteractionSource
+import androidx.compose.foundation.interaction.collectIsPressedAsState
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.heightIn
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+
+/**
+ * Position of a row within a grouped list (the Android-15 settings pattern): a
+ * run of rows shares one rounded container, full corners at the group's outer
+ * edges and small corners between, separated by small gaps. Copied from
+ * Calendula so the two apps read as one family.
+ */
+enum class Position { Top, Middle, Bottom, Alone }
+
+fun positionOf(index: Int, count: Int): Position = when {
+    count <= 1 -> Position.Alone
+    index == 0 -> Position.Top
+    index == count - 1 -> Position.Bottom
+    else -> Position.Middle
+}
+
+/**
+ * One row in a grouped list: an M3 [ListItem] over a tonal [Surface] whose
+ * corner radii come from its [position] (so a run of rows reads as a single
+ * rounded card). Corners morph further on press — the expressive shape play.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun GroupedRow(
+    title: String,
+    position: Position,
+    modifier: Modifier = Modifier,
+    summary: String? = null,
+    selected: Boolean = false,
+    minHeight: Dp = 72.dp,
+    leading: @Composable (() -> Unit)? = null,
+    trailing: @Composable (() -> Unit)? = null,
+    onClick: (() -> Unit)? = null,
+) {
+    val interaction = remember { MutableInteractionSource() }
+    val pressed by interaction.collectIsPressedAsState()
+    val full by animateDpAsState(if (pressed) 36.dp else 22.dp, label = "fullCorner")
+    val small by animateDpAsState(if (pressed) 36.dp else 6.dp, label = "smallCorner")
+    val shape = when (position) {
+        Position.Alone -> RoundedCornerShape(full)
+        Position.Top -> RoundedCornerShape(
+            topStart = full, topEnd = full, bottomStart = small, bottomEnd = small,
+        )
+        Position.Middle -> RoundedCornerShape(small)
+        Position.Bottom -> RoundedCornerShape(
+            topStart = small, topEnd = small, bottomStart = full, bottomEnd = full,
+        )
+    }
+    val gap = when (position) {
+        Position.Top, Position.Middle -> Modifier.padding(bottom = 2.dp)
+        Position.Bottom, Position.Alone -> Modifier
+    }
+    val itemColors = if (selected) {
+        ListItemDefaults.colors(
+            containerColor = Color.Transparent,
+            headlineColor = MaterialTheme.colorScheme.onSecondaryContainer,
+            leadingIconColor = MaterialTheme.colorScheme.onSecondaryContainer,
+            supportingColor = MaterialTheme.colorScheme.onSecondaryContainer,
+            trailingIconColor = MaterialTheme.colorScheme.onSecondaryContainer,
+        )
+    } else {
+        ListItemDefaults.colors(containerColor = Color.Transparent)
+    }
+    val item: @Composable () -> Unit = {
+        ListItem(
+            headlineContent = { Text(title) },
+            supportingContent = summary?.let { text -> { Text(text) } },
+            leadingContent = leading,
+            trailingContent = trailing,
+            colors = itemColors,
+            modifier = Modifier.heightIn(min = minHeight),
+        )
+    }
+    val base = modifier
+        .fillMaxWidth()
+        .padding(horizontal = 16.dp)
+        .then(gap)
+    val containerColor = if (selected) {
+        MaterialTheme.colorScheme.secondaryContainer
+    } else {
+        MaterialTheme.colorScheme.surfaceContainerHigh
+    }
+    if (onClick != null) {
+        Surface(
+            onClick = onClick,
+            color = containerColor,
+            shape = shape,
+            interactionSource = interaction,
+            modifier = base,
+        ) { item() }
+    } else {
+        Surface(color = containerColor, shape = shape, modifier = base) { item() }
+    }
+}

app/src/main/java/de/jeanlucmakiola/floret/ui/common/ListChip.kt

@@ -0,0 +1,55 @@
+package de.jeanlucmakiola.floret.ui.common
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Checklist
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.unit.dp
+
+/**
+ * Soften a raw provider colour toward a pastel that fits the active theme —
+ * keeps the hue (lists stay recognisable), caps saturation so harsh sync
+ * colours stop screaming, pins brightness to read on light and dark. Copied
+ * from Calendula so the families' colours behave identically.
+ */
+fun pastelize(rawArgb: Int, dark: Boolean): Color {
+    val hsv = FloatArray(3)
+    android.graphics.Color.colorToHSV(rawArgb, hsv)
+    hsv[1] = (hsv[1] * 0.6f).coerceIn(0.25f, 0.65f)
+    hsv[2] = if (dark) 0.82f else 0.72f
+    return Color(android.graphics.Color.HSVToColor(hsv))
+}
+
+/**
+ * Leading avatar for a task list: a neutral round chip holding a checklist glyph
+ * tinted in the list's (pastelised) colour — the Calendula calendar-chip pattern,
+ * with a task icon for Floret.
+ */
+@Composable
+fun ListColorChip(color: Int, modifier: Modifier = Modifier) {
+    val dark = isSystemInDarkTheme()
+    Box(
+        modifier = modifier
+            .size(40.dp)
+            .clip(CircleShape)
+            .background(MaterialTheme.colorScheme.surfaceContainerHighest),
+        contentAlignment = Alignment.Center,
+    ) {
+        Icon(
+            Icons.Filled.Checklist,
+            contentDescription = null,
+            tint = pastelize(color, dark),
+            modifier = Modifier.size(22.dp),
+        )
+    }
+}

app/src/main/java/de/jeanlucmakiola/floret/ui/lists/ListsScreen.kt

@@ -1,7 +1,5 @@
 package de.jeanlucmakiola.floret.ui.lists
 
-import androidx.compose.foundation.background
-import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
@@ -12,23 +10,18 @@ import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.size
-import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyColumn
-import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.lazy.itemsIndexed
-import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.rounded.ListAlt
 import androidx.compose.material.icons.rounded.Add
 import androidx.compose.material.icons.rounded.ErrorOutline
 import androidx.compose.material.icons.rounded.Today
 import androidx.compose.material.icons.rounded.Upcoming
-import androidx.compose.material3.Card
 import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.ElevatedCard
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.ExtendedFloatingActionButton
-import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.Icon
 import androidx.compose.material3.LargeTopAppBar
 import androidx.compose.material3.MaterialTheme
@@ -39,19 +32,20 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.draw.clip
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
-import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import de.jeanlucmakiola.floret.R
 import de.jeanlucmakiola.floret.domain.SmartList
 import de.jeanlucmakiola.floret.domain.TaskFilter
+import de.jeanlucmakiola.floret.ui.common.GroupedRow
+import de.jeanlucmakiola.floret.ui.common.ListColorChip
+import de.jeanlucmakiola.floret.ui.common.positionOf
 
 /**
  * Home: smart lists (Today / Overdue / Upcoming / All) as tonal cards with live
@@ -105,7 +99,6 @@ private fun ListsContent(
             top = inner.calculateTopPadding(),
             bottom = inner.calculateBottomPadding() + 96.dp,
         ),
-        verticalArrangement = Arrangement.spacedBy(8.dp),
     ) {
         item { SmartGrid(state.smartCounts, onOpenFilter) }
 
@@ -114,8 +107,24 @@ private fun ListsContent(
         } else {
             item { SectionHeader(stringResource(R.string.lists_header)) }
             state.groups.forEach { group ->
-                item(key = "acct-${group.accountName}") {
+                item(key = "acct-${group.accountName}") { AccountHeader(group.accountName) }
-                    AccountGroupCard(group, onOpenFilter)
+                itemsIndexed(group.lists, key = { _, o -> o.list.id }) { index, overview ->
+                    GroupedRow(
+                        title = overview.list.name,
+                        position = positionOf(index, group.lists.size),
+                        minHeight = 72.dp,
+                        leading = { ListColorChip(overview.list.color) },
+                        trailing = {
+                            if (overview.openCount > 0) {
+                                Text(
+                                    overview.openCount.toString(),
+                                    style = MaterialTheme.typography.labelLarge,
+                                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                                )
+                            }
+                        },
+                        onClick = { onOpenFilter(TaskFilter.OfList(overview.list.id)) },
+                    )
                 }
             }
         }
@@ -180,74 +189,12 @@ private fun SmartCard(count: SmartCount, modifier: Modifier = Modifier, onClick:
     }
 }
 
-/** One account's lists as a single rounded surface card (grouped-list pattern). */
-@Composable
-private fun AccountGroupCard(group: AccountGroup, onOpenFilter: (TaskFilter) -> Unit) {
-    Column(Modifier.padding(horizontal = 16.dp)) {
-        AccountHeader(group.accountName)
-        Card(
-            modifier = Modifier.fillMaxWidth(),
-            shape = RoundedCornerShape(28.dp),
-            colors = CardDefaults.cardColors(
-                containerColor = MaterialTheme.colorScheme.surfaceContainerHigh,
-            ),
-        ) {
-            group.lists.forEachIndexed { index, overview ->
-                ListRow(overview) { onOpenFilter(TaskFilter.OfList(overview.list.id)) }
-                if (index < group.lists.lastIndex) {
-                    HorizontalDivider(
-                        color = MaterialTheme.colorScheme.outlineVariant,
-                        modifier = Modifier.padding(start = 52.dp),
-                    )
-                }
-            }
-        }
-    }
-}
-
-@Composable
-private fun ListRow(overview: ListOverview, onClick: () -> Unit) {
-    Row(
-        modifier = Modifier
-            .fillMaxWidth()
-            .clickable(onClick = onClick)
-            .padding(horizontal = 20.dp, vertical = 20.dp),
-        verticalAlignment = Alignment.CenterVertically,
-    ) {
-        ColorDot(overview.list.color, size = 16.dp)
-        Spacer(Modifier.width(16.dp))
-        Text(
-            text = overview.list.name,
-            style = MaterialTheme.typography.titleLarge,
-            modifier = Modifier.weight(1f),
-        )
-        if (overview.openCount > 0) {
-            Text(
-                text = overview.openCount.toString(),
-                style = MaterialTheme.typography.titleMedium,
-                color = MaterialTheme.colorScheme.onSurfaceVariant,
-            )
-        }
-    }
-}
-
-@Composable
-private fun ColorDot(colorInt: Int, size: Dp = 12.dp) {
-    val color = if (colorInt != 0) Color(colorInt) else MaterialTheme.colorScheme.primary
-    Box(
-        Modifier
-            .size(size)
-            .clip(CircleShape)
-            .background(color),
-    )
-}
-
 @Composable
 private fun SectionHeader(text: String) {
     Text(
         text = text,
         style = MaterialTheme.typography.titleMedium,
-        modifier = Modifier.padding(start = 16.dp, end = 16.dp, top = 16.dp, bottom = 4.dp),
+        modifier = Modifier.padding(start = 28.dp, end = 28.dp, top = 16.dp, bottom = 4.dp),
     )
 }
 
@@ -255,9 +202,9 @@ private fun SectionHeader(text: String) {
 private fun AccountHeader(text: String) {
     Text(
         text = text,
-        style = MaterialTheme.typography.labelLarge,
+        style = MaterialTheme.typography.labelMedium,
         color = MaterialTheme.colorScheme.onSurfaceVariant,
-        modifier = Modifier.padding(start = 4.dp, top = 12.dp, bottom = 6.dp),
+        modifier = Modifier.padding(start = 28.dp, end = 28.dp, top = 12.dp, bottom = 4.dp),
     )
 }