Fix Shareousel crash when recomposing

Recomposition could cause a crash when initial position was no longer in
the LazyRow. This fixes it by encapsulating the problematic array
indexing within the remember block so that it is only performed on the
first composition when it is guaranteed to be a valid index position.

Test: Manual test using ShareTest
BUG: 383852288
Flag: EXEMPT Bugfix
Change-Id: Ie6b322d449ddc5c83d9d4e481967c2511b165290

1 files changed, 8 insertions, 6 deletions

diff --git a/java/src/com/android/intentresolver/contentpreview/payloadtoggle/ui/composable/ShareouselComposable.kt b/java/src/com/android/intentresolver/contentpreview/payloadtoggle/ui/composable/ShareouselComposable.kt
index 5b368084..c51021a8 100644
--- a/java/src/com/android/intentresolver/contentpreview/payloadtoggle/ui/composable/ShareouselComposable.kt
+++ b/java/src/com/android/intentresolver/contentpreview/payloadtoggle/ui/composable/ShareouselComposable.kt
@@ -33,9 +33,9 @@ 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.LazyListState
 import androidx.compose.foundation.lazy.LazyRow
 import androidx.compose.foundation.lazy.itemsIndexed
-import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.foundation.selection.toggleable
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.systemGestureExclusion
@@ -130,15 +130,17 @@ private fun PreviewCarousel(previews: PreviewsModel, viewModel: ShareouselViewMo
         // Do not compose the list until we have measured values
         if (measurements == PreviewCarouselMeasurements.UNMEASURED) return@Box
 
-        val carouselState =
-            rememberLazyListState(
-                prefetchStrategy = remember { ShareouselLazyListPrefetchStrategy() },
-                initialFirstVisibleItemIndex = previews.startIdx,
-                initialFirstVisibleItemScrollOffset =
+        val prefetchStrategy = remember { ShareouselLazyListPrefetchStrategy() }
+        val carouselState = remember {
+            LazyListState(
+                prefetchStrategy = prefetchStrategy,
+                firstVisibleItemIndex = previews.startIdx,
+                firstVisibleItemScrollOffset =
                     measurements.scrollOffsetToCenter(
                         previewModel = previews.previewModels[previews.startIdx]
                     ),
             )
+        }
 
         LazyRow(
             state = carouselState,