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kotlinlang

Screen Recording 2022-12-19 at 11.42.07 am.mov

Hi all - trying to make my `LargeTopAppBar` collapse when you scroll on the list view - but it doesn't seem to work. full code in the :thread:
```val scrollState = rememberTopAppBarScrollState()
val scrollBehavior = TopAppBarDefaults.enterAlwaysScrollBehavior(state = scrollState)

LargeTopAppBar(
  modifier = Modifier.windowInsetsPadding(WindowInsets.statusBars),
  ..
  scrollBehavior = scrollBehavior
)```

Am i setting this up wrong? :thinking_face:
```val scrollState = rememberTopAppBarScrollState()
val scrollBehavior = TopAppBarDefaults.enterAlwaysScrollBehavior(state = scrollState)

LargeTopAppBar(
  modifier = Modifier.windowInsetsPadding(WindowInsets.statusBars),
  title = {
    if(state is Idle) Column {
      Text(
        text = state.entity.request.parts.values.joinToString(" • "),
        style = MaterialTheme.typography.headlineSmall
      )

      Text(
        text = state.entity.request.parts.keys.map { it.text }.joinToString(" • "),
        style = MaterialTheme.typography.bodySmall
      )
    }
  },
  actions = {
    if (isStacked) IconButton(onClick = onFullScreen){
      Icon(Icons.Rounded.OpenInFull, null)
    }
  },
  navigationIcon = {
    IconButton(
      onClick = onBack,
      modifier = Modifier.padding(end = 8.dp)
    ) {
      val icon: ImageVector = when {
        isStacked -&gt; Icons.Rounded.Close
        else -&gt; Icons.Rounded.ArrowBack
      }

      Icon(
        painter = rememberVectorPainter(icon),
        contentDescription = null, // TODO
      )
    }
  },
  scrollBehavior = scrollBehavior
)```

how are you connecting the behaviour to your Scaffold or LazyColumn?

yeah you need to link that scroll behaviour with your scrollable content, and you can probably drop the `val scrollState = rememberTopAppBarScrollState()` altogether in your case

so your code becomes something like:
```val scrollBehavior = TopAppBarDefaults.enterAlwaysScrollBehavior()

Scaffold(
    modifier = Modifier
        .windowInsetsPadding(WindowInsets.statusBars)
        .nestedScroll(scrollBehavior.nestedScrollConnection),
    topBar = {
        LargeTopAppBar(
            ...
            scrollBehavior = scrollBehavior
        )
    }
    content = { ... }
)```

Screen Recording 2022-12-19 at 2.14.05 pm.mov

aha! I missed that part! Thanks :raised_hands: