Can I wrap Jetpack Compose inside an Android Custom View like below?

class CustomView @JvmOverloads constructor(
        context: Context,
        attrs: AttributeSet? = null,
        defStyleAttr: Int = 0)
    : View(context, attrs, defStyleAttr) {

    // Some Jetpack Compose drawn item

}

I have also check in https://stackoverflow.com/q/69987040/3286489

Hi! Does anyone know what's the use case for the

parent

argument in the 

setContent

 extension?

public fun ComponentActivity.setContent(
    parent: CompositionContext? = null,
    content: @Composable () -> Unit
) {...}

I've never seen a sample using this argument 🤔

Any ideas how to make a parallax like this in a LazyColumn?

Hello here! I would like to use Compose in one of my professionnel project with a large code base but I have a huge performance impact when I’m using a LazyColumn with a pretty simple row (a Row with some texts inside). Attached to this message, you can find an example on a OnePlus 7T with the GPU usage overlay but it is worst on a Motorola G8 Plus where it is just not usable... We extracted the list on an external project where it is better but we have always a lag on some devices (Motorola G8 Plus impacted). Here the GitHub repository if some of you want to check the source code: https://github.com/adrienbusin/TestComposeLags For information, yes the build is in debug but it is clearly not better with a release version...

One screen (characterized mainly by an array of `Button`s) of my Compose-only app has become really sluggish on Android 12, most noticeably in the emulator (I tried a Pixel 4a and Pixel 5). I am on Compose 1.1.0-beta02/AS Bumblebee Beta 3, but I tested back to alpha-06 and with prior versions of my app and I only see the issue on API 31, not API 30. (I am running the debug version of my app, like I have been, in all cases.) Are there known performance issues before I try to narrow this down further?

hi! does anyone know how to center vertically the Icon or trailing elements in a ListItem? ...

Hello! I recently experimenting a bit with Compose Canvas and I stuck at animation. I have the Row with Canvas and vertical Bars, when I click on a bar, it gets selected and background of this bar changes. What I would love to achieve is that this background will animate from bottom to top on each click, so the user will have nice click experience. Demo in 🧵 Basically, I need to use

animateFloatAsState

to animate height, but I do not know how to reset this on each click on next bar in the chart.

Hi folks! Is there any easy way to calculate total scroll value of the list?

object : NestedScrollConnection {
            override fun onPreScroll(available: Offset, source: NestedScrollSource): Offset {
                totalScrolled -= available.y
}

if the list reaches the top and I keep scrolling up

available.y

will still be positive therefore scrolling back to the initial position will not make

totalScrolled

as 0

How to call a Composable fun from coroutine while collecting a flow? compiler said you can't use Composable fun from another non Composable fun.

Does BasicTextField, TextField or OutlinedTextfield have a mechanism for showing error message similar to what is achieved using TextView's setError() and getError()?

Screenshot from 2021-11-16 15-10-07.png

Is there a way to open a

Composable

screen when the app receives a notification while it’s in the foreground without using a

PendingIntent

? Cc: @louiscad

If I pull in

androidx.compose.ui:ui:1.1.0-alpha03

I can view the source code in Android Studio. But if I pull in

1.1.0-alpha04

(or anything past that) I can't, I just get ugly decompiled .class files -- any idea why that is? Was source omitted from later builds? How could I check that?

Hi, is there any way to add this kind of fade out effect in TextField in horizontal direction?

@Pedro Gomez Is there a way to add Idling resources to Coil Image loading in compose UI for Screenshot testing? I have few cases, where I use the same Image Url but only first test does not load the image and rest all screenshots have the image @theapache64

Why do the docs use 

by remember { mutableStateOf(selection) }

 instead of

rememberUpdatedState

 ? Seems like the latter is the same just more refined?

What’s the right way to deeplink into another activity (interoperability) and make it part of the

NavHost

backstack? I need the activity to launch from a specific destination, so that user is navigated back to that after exiting the activity.

I am passing

SnapshotStateList<Char>

to a composable function. But any changes to

SnapshotStateList's item(s)

doesn’t re-trigger the

LaunchedEffect

Any idea why? Code in thread.

Does any one have any intel on when

beta-03

is going to be released?

I’ve got a problem where my VM gets re-initialized when moving between composable screens. Not quite sure on how to go about fixing it. My VM is initialized by

Koin

as shown below.

import org.koin.androidx.viewmodel.dsl.viewModel
import org.koin.dsl.module

actual val myScreenModule = module {
    viewModel { MyScreen() }
}

The VM itself extends

import androidx.lifecycle.ViewModel

class. And inside my

NavGraphBuilder.addMainGraph

block I instantiate the screen

composable(MyScreen.route) {
        MyScreen(
            viewModel = get(),
        )
    }

Not quite sure how to go about things here: is this expected behaviour and I should store VM state inside or is there some other way that I could keep the state?

I've thought it would be great if node type emitted from

@Composable

is defined with the annotation. (I know this can't be adopted as it is a huge breaking change) Now there are a lot of things using Compose runtime; Compose UI, Glance, Some terminal(I do not remember the name), and can be extended freely. If both Compose UI and Glance had

Text

, it would be a lot confusing. 🧵

Hi! I have a fragment and inside it there is a

ComposeView

. Could I use this composeView for two types of Composable dialogs which is shown on the screen dynamically depending on backend results? Or should I use one composeView per one type of dialogs?

What is the best approach to play a youtube video in android jetpack compose app?

I'm kind of going crazy on not being able to get this layout to look quite right in my app. Essentially, the top horizontal bar is a carousel made up of RedComposable's, and then there is a green composable list, which is a vertical scrolling column. The GreenComposable includes a RedComposable. The trouble I'm having is how to size the RedComposable. My design team said "The Red should be 40% of the green, and then that size of the red should be used in the horizontal scroller" How would I do that in compose?

I've been consuming a lot of the talks and articles about how Compose works behind the scenes, mostly from Leland but others too. I've learned a lot about slot tables, recompition phases, positional memoization etc but one piece I feel like I'm missing is this - how does actual emission of UI work? tl;dr; does anyone have good resources on the actual rendering conversion that happens behind the scenes?

Any built-in way to determine if a

@Composable

is being presented in a

@Preview

or not? (Something in Locals?) I know it shouldn't care; but sometimes in the real world there are practical reasons. In this case the Coil SVG library is crashing in Previews for some class-loader related reason; I need some flag to suppress registering of the SVG handler in Previews so I can get on with building the rest of the View.

When trying to update to kotlin 1.6.0 in my project using compose, I get the following error :

e: This version (1.0.5) of the Compose Compiler requires Kotlin version 1.5.31 but you appear to be using Kotlin version 1.6.0 which is not known to be compatible. Please fix your configuration (or

suppressKotlinVersionCompatibilityCheck

but don't say I didn't warn you!).

Is there an available version of the compose compiler that supports kotlin 1.6.0? Ours is set to

kotlinCompilerExtensionVersion = "1.0.5"

Thanks for your help!

I am trying to pass a test instance of one of my data classes into one of my composables in a preview and I’m getting

java.lang.NoClassDefFoundError: Could not initialize class...

whenever I try to create the data class instance within my preview composable function. Has anyone else run into this before?

Hi all. Tivi defines a nice helper to work with the new

flowWithLifecycle

API. Since new lifecycle APIs are stable in 2.4.0, are there any plans to add similar helpers in Compose artifacts?

I have:

class ScreenAState {
    val people = mutableStateListOf<PersonUIWrapper>()
}

data class PersonUIWrapper(var selected: Boolean, val person: Person)

then in an onclick of a person in my list I do

TextButton(onClick = {
    it.selected = true
})...

but my code doesn't recompose, and therefore doesn't show a checkmark. Is my PersonUIWrapper supposed to use snapshot state internally for it's two fields?