This message was deleted.

Ive been doing

LaunchedEffect(list.size){ scrollToTop() }

in order to scroll my

LazyColumn

to the top whenever the list size changes. This works great, but it also scrolls the list to the top whenever I navigate back to it since the LaunchedEffect is restarted. I could work around this with

rememberSaveable

, but that doesnt seem ideal. Is there another better approach?

Does

AnimatedVisibility

disable/ignore the padding of its children?

AnimatedVisibility(visible = isExpanded) {
    Divider(
       modifier = Modifier.padding(bottom = 12.dp).fillMaxWidth(),
       color = Gray200,
       thickness = 2.dp
    )

    OutlinedButton(
        modifier = Modifier.padding(top = 12.dp),
        onClick = {}
    ){}
}

The padding of both divider and button has no effect when wrapping them within AV, but when I comment AV out the padding works well, am I missing anything?

Does this look wrong to anyone?

LaunchedEffect(viewModel.screenState.something != null)

Should it instead be

LaunchedEffect(viewModel.screenState.something

and then do the null check inside (or outside of) the LE?

Try turning the item into smth like

Spacer(Modifier)

and see if it still recomposes. If not, then the problem is in the item itself. From guessing I’d say it should not recompose unless you’re inside the item reading something related to the scroll-state or some other state which changes while scrolling

Hey guys! Is there any way to control two horizontal pagers with a single pager state? I want to control them bidirectional, but for now I only found a solution to use different states and write some logic to control oneeachother

If I try to run a composable

@Preview

on a device, I get an error of the sort: https://stackoverflow.com/q/68554294

Does someone know how to setup a Instagram-Like BottomNavBar? Example: The “Home” Icon in the BottomNavBar stays selected even when the user clicks on a profile or the comments of a post. Also when the user clicks the “Home” icon again it goes back to the feed but only if he already selected the Home tab. When the user is on the Explore tab and clicks back to Home he continues right where he left off. I tried it with Nested Navigation but couldn’t get it right, am I on the right path?

Hey guys! Is there any implementation in Material3 swipe to dismiss on LazyColumn?

rememberDismissState

is missing in M3. Pls. any example or tutorial? I read the documentation for compose and material3 and I can’t find anything even on github. Thanks a lot 🙏🏻

Hi guys, I’m doing the Instagram clone. I’m stuck in the User section. There has to be a current user and other users. Do I need to do all the operations in a single UserViewmodel or do I need to separate them as CurrentUserViewModel and otherUserViewModel? Or How should be best practice?

Well, compose officially won me over fully. Getting back into AOSP fw dev and the view system is such a drag to work with 😆

Here is a paging problem: the data of items in

LazyColumn

comes from two different APIs. “A-API” is the basis of “B-API” so paging requests complete item data is very slow. The data of the “B-API” is not urgently needed. I hope it can be loaded lazily. Is there any way?

Well, does anyone here understand M3 design tokens please? Why Material Theme Builder generates System token and not reference token?

How to change the pressed color of a clickable box? I don't mean the box's color, but the click's color 🤔

btw, is anyone besides me having some issues with blend mode on draw modifiers within the components of a lazy column? When the scroll reaches the top or bottom of the page the components get the usual stretch, and when that happens the blend overlay effect just dies until the stretch finishes.

(Animations 🌠*):* Ive managed to fine tune my app to some extreme smoothness, but I cant really seem to acheive the same smoothness when using

AnimatedContent

. Theres almost always a slight stutter when using it to transition to a new screen; and its almost always exclusive to the first time the screen is shown - from there and on the transition is smooth for as long as the app is running. Using R8, baseline profiles, etc. Is this a known issue; or am I simply doing something wrong? Ill attach a simple code example in the thread. 🧵

Heres a discussion about it! https://kotlinlang.slack.com/archives/CJLTWPH7S/p1662557589916869

Are you going to make some app that does this? 👀

Hi, how i use the api response from viewModel to Composable function? Like i have a this code, how i observe the flightsList and show the data in Composable function?

private val _flightList = MutableLiveData<List<FlightListingUiModel>>()
val flightsList: LiveData<List<FlightListingUiModel>> = _flightList

Does anyone know if there is a way to keep

remember

state alive between calls to

movableContentOf

? I currently have a situation where I am doing something like this:

val moveable = remember { moveableState { DrawAnItem() } }
if(visible) moveable.invoke()

The problem is that when “visible” gets toggled, all `remember`ed state inside

DrawAnItem

is reset. However, if I do this:

val moveable = remember { moveableState { DrawAnItem() } }
if(visible) moveable.invoke()
else {
    Box(modifier = Modifier.alpha(0f)) {
        moveable.invoke()
    }
}

the `remember`ed items are properly remembered in between calls to “visible”. This obviously isn’t a very good solution, but I’m trying to figure out how to keep a composable “alive” when I know that I’m going to render it again in the not-too-distant future.

Hi, how i show compose skeleton while making api call and on the response show UI instead of skeleton?

Just to make it clear. The screenshot is on a Left and Right variant of a button.

Is the calculation of

currentCompositeKeyHash

aka

currentComposer.compoundKeyHash

well-defined?

rememberSaveable()

uses it for save keys, but if I add something like

key(objectWithDefaultHashKey)

to my Compose hierarchy then I assume the save key will be different before and after process death, and whatever I saved would not be restored, right? My particular use case has

key(enumValue)

, which I assume would also have different hash values before and after process death, based on what

Enum.hashCode()

does. Would I be in the clear then, as far as

rememberSaveable()

goes, if I used something like

key(enumValue.myStringLabel)

instead? The reason for my question is this comment from a Googler: https://issuetracker.google.com/issues/152014032#comment4

I’m trying to get

@Preview

working in a multi module project. Has anyone had trouble doing this?

Does anyone have advice on how to keep a

LazyColumn

at a specific scroll amount, instead keeping an item/key visible, when inserting items? (i.e. sticking to the top of the list when inserting at zero)

What is the right way to provide state for a specific item of a

LazyColumn

? Currently the state is applied to all items. Example code:

@Composable
private fun ScannerList(
    items: List<DiscoveredBluetoothDevice>,
    connectionState: ConnectionState, // StateFlow in view model
) { ...

private fun ScannerListItem(
    connectionState: ConnectionState,
    ...
) {
    ListItem(
       trailing = {
           Button(onClick = {  // trigger change of connectionState in view model })
           val iconColor: Color = when (connectionState) { ConnectionState.Connected -> Green600 ... }
       }
    ) 
}

Do I have to narrow down

List<DiscoveredBluetoothDevice>

so I get sth like

List<DiscoveredBluetoothDeviceItem>

?

hi guys, The viewmodel is cleared when popbackstack is called or when I press the back button . But when I come back to the screen it doesn’t start again. Is there a proper solution to this?

Anyone from accompanist here? I'm only seeing 0.26.2-beta but according to ben-manes version plugin, I'm out of date? https://github.com/google/accompanist/releases

During some lab exercises targeting Compose usage on big screens with lots of Composables, I discovered a scenario where excessive slot table operations were rendering the UI unresponsive for tens of seconds. Maybe of interest to the Compose team? (It's a Desktop/Web/WASM lab application but the slot table is part of Compose runtime, so this applies to other platforms, too.) Details in 🧵.