Hello all, wondering if anyone has had issues with animateScrollToItem using a LazyColumn. I have a ...

# compose

[Billy Newman]

Hello all, wondering if anyone has had issues with animateScrollToItem using a LazyColumn. I have a list of items, users can add new items, on add I would like to scroll to the top of the new item. Trying something like this:

val items by state.items
  val scope = rememberCoroutineScope()
  var itemCount by remember { mutableStateOf(state.items.value.size) }

  LazyColumn(
    state = listState,
    modifier = Modifier.fillMaxHeight()
  ) {
    item {
      HeaderContent()
    }

    itemsIndexed(items) { index, item ->
      ItemContent(item)
    }

    if (itemCount < items.size) {
      scope.launch {
        // items.size, not items.size - 1 to account for header
        listState.animateScrollToItem(items.size)
      }

      itemCount = items.size
    }
  }

This works most of the time. However, every so often the scroll will end at the bottom or middle of the newly added item, not the top of the new item.

[Kirill Grouchnikov]

May or may not be related to https://issuetracker.google.com/issues/182983176

[Dominaezzz]

Idk if it's related but you should replace scope.launch with LauncedEffect .

[Dominaezzz]

Yeah that should definitely be LaunchedEffect(items.size) . I think it's related now.

[Billy Newman]

Using LaunchedEffect inside LazyColumn produces

@Composable invocations can only happen from the context of a @Composable function

[Dominaezzz]

Do it outside the LAzyColumn .

[Billy Newman]

Same thing, first item add, scrolls to bottom of item, not top

[Billy Newman]

Still very random, sometimes it will scroll to the middle, other times the bottom. Most of the time it is working and scrolling to the top of the new item.

[MBegemot]

I have exactly the same issue, and also ScrollTo misbehaves .... what is weird is the random nature of the error now I work, now I don't

[Billy Newman]

I am going to put together a small sample on github, and then possibly write up a ticket. There is for sure something going on here.

[Billy Newman]

For anyone interested: https://github.com/newmanw/compose-scroll