IssueTracker

Versioning and Device Details

Jetpack Compose version: 2025.02.00 (observed at least as far back as 2024.10.01) Jetpack Compose component used: Row Android Studio Build: #AI-242.23726.103.2422.12816248, built on December 17, 2024 Kotlin version: 2.1.10

Device Model: (Emulator) Pixel 9 API 35 Android Version: API 35 TalkBack Version: version 15.0.0.639625893

Issue Description

When displaying items in a horizontally-scrolling Row, the items not currently on screen are ignored when navigating "back" onto the Row--even when traversal order is explicitly defined.

Expected behavior: When navigating backwards, it is expected that the last item in a traversal group is visited first.

Actual behavior: When navigating backwards, the last visible item is visited first.

Steps to Reproduce or Code Sample to Reproduce:

1. Have a screen with a horizontally scrolling row containing more items than can fit on a single screen. Code Sample:

@Composable
fun Content() {
  Scaffold { paddingValues ->
    Column(modifier = Modifier.padding(paddingValues)) {
      TraversableRow(10)
      Text("Some other content")
    }
  }
}

@Composable
fun TraversableRow(numItems: Int) {
  val scrollState = rememberScrollState()
  Row (
    modifier = Modifier.fillMaxWidth()
      .horizontalScroll(scrollState)
      .semantics {
        isTraversalGroup = true
        collectionInfo = CollectionInfo(rowCount = 1, columnCount = numItems)
      },
  ) {
    repeat(numItems) { index ->
      RowItem(index)
    }
  }
}

@Composable
fun RowItem(index: Int) {
  Box(
    modifier = Modifier.run {
      semantics {
        traversalIndex = index.toFloat()
        collectionItemInfo = CollectionItemInfo(
          rowSpan = 1,
          rowIndex = 0,
          columnSpan = 1,
          columnIndex = index
        )
      }
    }
  )
    Text(
      modifier = Modifier
        .padding(8.dp),
      text = "Item #${index + 1}"
    )
}

2. Using talkback, navigate to any item on screen "after" horizontal row.
3. Swipe "back"/to the left to navigate to last item in row.
4. Observe that the item navigated to is the last item visible on screen, but not necessarily the last item in the list.

Stack trace (if applicable): N/A