fix: refresh statistics by-book covers

Author: HuangAntimony

app/src/main/java/moe/antimony/hoshi/features/statistics/StatisticsCalculations.kt

@@ -282,6 +282,7 @@ internal fun distributionRows(
                 DailyTargetType.Duration -> contribution.readingSeconds
             }
             BookDistributionRow(
+                bookId = contribution.bookId,
                 title = contribution.title,
                 coverPath = contribution.coverPath,
                 characters = contribution.characters,

app/src/main/java/moe/antimony/hoshi/features/statistics/StatisticsDistributionList.kt

@@ -15,6 +15,7 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.key
 import androidx.compose.runtime.produceState
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Alignment
@@ -51,7 +52,9 @@ internal fun StatisticsDistributionList(
         verticalArrangement = Arrangement.spacedBy(10.dp),
     ) {
         rows.forEach { row ->
-            DistributionRow(row = row)
+            key(row.bookId) {
+                DistributionRow(row = row)
+            }
         }
     }
 }
@@ -117,6 +120,7 @@ private fun DistributionCover(row: BookDistributionRow) {
         BookCoverBitmapCache.get(coverSource)
     }
     val bitmap by produceState(initialValue = cachedBitmap, key1 = coverSource) {
+        value = cachedBitmap
         if (cachedBitmap == null) {
             value = BookCoverBitmapCache.load(coverSource)
         }

app/src/main/java/moe/antimony/hoshi/features/statistics/StatisticsModels.kt

@@ -141,6 +141,7 @@ internal data class StatisticsTrendPoint(
 )
 
 internal data class BookDistributionRow(
+    val bookId: String,
     val title: String,
     val coverPath: String?,
     val characters: Int,

app/src/test/java/moe/antimony/hoshi/features/statistics/StatisticsCalculationsTest.kt

@@ -259,6 +259,24 @@ class StatisticsCalculationsTest {
         assertEquals(75, byDuration.first().percent)
     }
 
+    @Test
+    fun distributionRowsCarryBookIdsForStableUiKeys() {
+        val rows = distributionRows(
+            listOf(
+                day(
+                    "2026-06-30",
+                    contributions = listOf(
+                        contribution(bookId = "alpha-id", title = "Same Title", characters = 2_000, seconds = 600.0),
+                        contribution(bookId = "beta-id", title = "Same Title", characters = 1_000, seconds = 300.0),
+                    ),
+                ),
+            ),
+            StatisticsTargetSettings(),
+        )
+
+        assertEquals(listOf("alpha-id", "beta-id"), rows.map { it.bookId })
+    }
+
     private fun day(
         date: String,
         characters: Int = 0,

docs/CHANGELOG.md

@@ -13,6 +13,7 @@ Historical release notes before v1.3.0 live in [CHANGELOG_ARCHIVE.md](CHANGELOG_
 ### Fixed
 
 - Keep the Statistics tab visible after enabling it and switching away from Settings.
+- Refresh Statistics by-book covers when changing calendar ranges.
 
 ## [v1.3.0] - 2026-07-01