Question about State . Why does’t the second way work? 1. Work:

var refreshing by remember { mutableStateOf(false) }
LaunchedEffect(refreshing) {
    if (refreshing) {
        delay(2000)
        refreshing = false
    }
}

SwipeRefresh(
    state = rememberSwipeRefreshState(isRefreshing = refreshing),
    onRefresh = { refreshing = true },
) { ... }

2. Can’t enter refreshing state:

val state = rememberSwipeRefreshState(isRefreshing = false)

LaunchedEffect(state.isRefreshing) {
    if (state.isRefreshing) {
        delay(2000)
        state.isRefreshing = false
    }
}

SwipeRefresh(
    state = state,
    onRefresh = { state.isRefreshing = true },
) { ... }

I get an exception here about FocusRequester not being initialized

val passwordRequester = remember { FocusRequester() }

        Card(
            modifier = Modifier
                .fillMaxWidth()
                .padding(horizontal = 32.dp),
            elevation = 4.dp
        ) {
            Column(
                modifier = Modifier.padding(16.dp),
                horizontalAlignment = Alignment.CenterHorizontally
            ) {
                EmailInput(
                    modifier = Modifier.fillMaxWidth(),
                    email = email,
                    onEmailChanged = onEmailChanged
                ) {
                     // HERE
                    passwordRequester.requestFocus()
                }

                Spacer(modifier = Modifier.height(16.dp))

                PasswordInput(
                    modifier = Modifier.focusRequester(passwordRequester),
                    password = password,
                    onPasswordChanged = onPasswordChanged,
                    onDoneClicked = onAuthenticate
                )
            }
        }

Is there a tutorial somewhere on out-of-flow positioning? E.g. how to implement things like CSS'

position: absolute

. What's the correct way to do something like display a shape that is above the rest of the contents?

If I have a project where I don't want to have a dependency on Compose, and I define a

androidx.compose.runtime.Immutable

annotation class locally, will the compiler plugin pick it up if I use that project as a dependency in another project?

how can I use collections functions inside of a composable function? Like i need to pass the @composable context to the map function on a flow. Example :

val windowSize: State<DpSize> = windowSize().map {
                with(LocalDensity.current) {
                    DpSize(it.first.toDp(), it.second.toDp())
                }
            }.collectAsState(DpSize(800.dp, 600.dp))

is there a clean way to do this?

Is is possible to get a CompositionLocalValue for a specific keyed group? • key(root) -- CompositionLocalProvider provides 1 --- key(foo) --- same CompositionLocalProvider provides 42 I would like to the value 1 from a Composable inside the key foo.

Why changing snapshot state from background thread during composition causing a crash? 🧵

Question: Can Coil ignore the subsequent calls with same url until first call is success? Scenario:

@Composable
fun Foo() {
  // call to load image from coil
}

Foo makes image call when on its first composition and due to any reason if Foo is recomposed before first call could be a success Coil makes another image load call Is there a way to avoid this? cc @Colin White

Hi all! I’m trying to implement DotsIndicator for HorizontalPager on Compose but I am stuck with the implementation. Does anyone have an idea?

I got this crash in my crashlytics today and it doesn’t have the triggering point (where it triggered from).

Fatal Exception: java.lang.IllegalArgumentException
Cannot round NaN value.
kotlin.math.MathKt__MathJVMKt.roundToInt (MathKt__MathJVMKt.java:1132)
androidx.compose.animation.core.VectorConvertersKt$IntOffsetToVector$2.invoke-Bjo55l4 (VectorConverters.kt:172)

It looks like its thrown from the animation framework . Full stacktrace in 🧵

How can I make this blur effect with Jetpack compose ?

I had the assumption that chaining Modifiers with

.then()

would replace the configuration of earlier modifiers. Now I stand corrected that an application of the

.padding(...)

modifier and an additional

Modifier.padding(...)

applied via

.then()

is actually additive. Is this really so or did I hit a weird bug here? I looked into the implementation of padding and this just measures / places the contents, I guess the culprit might be somewhere in

CombinedModifier

which I haven’t fully understood how it works (and if there is special code somewhere that folds “padding” modifiers by adding their values together).

Are there any API’s or libs to help with notifications?

Hey @Doris Liu I tried to create a custom VectorConverter for animating image scales. It didn't work out. I think I have to do more low-level or subclass the parent ContentScale interface. More in thread.

I’m building my app in Jetpack Compose and use one ViewModel for every feature/screen. Now I need to access the login state from everywhere inside the app, I also have a coin system where I need access to from every screen. How do I accomplish this? My first idea was to put the login state and coin state inside a “MainViewModel” and then use this in every Screen for example in my “SettingsScreen” composable use “SettingsViewModel” and “MainViewModel”. But I’m not sure if this is a good practice to use two viewModels in one screen. How can I have access to the Login state and the Coins in every screen?

I’m not sure if this is a bug or I’m missing something, just looking for validation. The following renders nothing in either preview or at application runtime:

val someFun: (@Composable () -> Unit)? = null
someFun?.invoke() ?: BasicText(text = "Foo")

Edit: Found the issue in the bug tracker: https://issuetracker.google.com/issues/198511576. Unfortunately, it’s still not fixed.

Whats the best way to pull this off? I want to be able to

.clip()

with an inverted shape, so to say. A coloured circle shape wouldn't work here because the surface colours are all transparent.

Does anyone know if there's an Android Studio plugin or something similar that could export the images for every preview? It would be helpful to share preview with designers.

We are getting a crash due to illegal state read.

java.lang.IllegalStateException: Reading a state that was created after the snapshot was taken or in a snapshot that has not yet been applied

But we are not able to figure out which part of our source is causing this problem since all of the stacktrace points to android framework, compose runtime and animation library. Full stacktrace in the 🧵 Note: the crash is intermittent and we are able to reproduce it a few times, when the app is changing orientation from landscape back to portrait. Can anyone help us figure out how we can get to the root cause for this crash?

Getting a

ClassCastException

here. Seems like a Compose compiler/runtime bug.

Is there any smart way to prevent overlapping range values on a rangeSlider?

Can we give Animation to a Card which will display and give a visual like SnackBar is displayed. How to achieve this SnackBar kind of Animation ??

Hey guys, pretty broad question - assuming that I create my own CustomTheme (https://developer.android.com/jetpack/compose/themes/custom), how can I share it efficiently between screens, given that I migrate existing XML Fragment-based app to Compose? E.g. I migrate two separate screens to Compose, and they both are built like this:

CustomTheme {
   // screen A content
}

CustomTheme {
  // screen B content
}

Won't this recreate my fonts/colors all over again? What would be the best approach here?

Hey everyone 👋 how do you usually handle your higher composables (let's say a whole screen content) when that composable has a lot of parameters?

I have a composable which triggers a notification. Is there a best practice in Compose for how to obtain the

Intent

for the notification’s

setContentIntent()

? I’m trying to avoid having the composable know about its host Activity. Clicking the notification will launch that Activity. I can think of a few things I could do: • Pass in a lambda like

intent: () -> Intent

to invoke anytime I need an intent • Pass in the Activity

Class<?>

• CompositionLocal? (bad idea?)

Is it possible to animate changes between two inputs of a

LazyColumn

?

LazyColumn {
    tasksList.forEach { task ->
        item {
            TaskItem(
                taskName = task.name,
                onStartTask = { onStartTask(task) }
            )
        }
    }
}

I'd like to animate a

TaskItem

if the corresponding

Task

object is not present in the next

tasksList

passed to

LazyColumn

Hey everyone, We have some of our compose test execute as instrumentation as well as unit test via robolectric. On compose version

1.0.5

all tests are executed successfully. But now we are trying to upgrade the compose version to

1.1.0

but some of the test fail when executed as unit test. But the same test work when executed as an instrumentation test. We have tried to update robolectric version to the latest

4.8.1

but that didn't work. After debugging a bit, it looks like the following step doesn't complete execution.

rule.onNodeWithText("some text").assertExists()

Internally it ends up in a loop in

RobolectricIdlingStrategy.runUntilIdle()

. Anyone who has faced similar issue?

Is there a way to test

Modifier.padding

?