kotlinlang #compose

. My shadow is displayed but it isn’t the same shadow applied around all my shape. Can it be possible to avoid a bigger shadow at the bottom and to have the exact same shadow around all the box?

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@Composable
fun CircleProgress(
    angle: Int
) {
    Box(
        Modifier
            .fillMaxSize()
            .padding(80.dp)
            .shadow(elevation = 8.dp, shape = CircleShape)
            .background(color = Color.White, shape = CircleShape)
            .padding(10.dp)
            .drawBehind {
                drawArc(
                    color = Color.Red,
                    startAngle = -90f,
                    sweepAngle = angle.toFloat(),
                    useCenter = false,
                    style = Stroke(width = 30f, cap = StrokeCap.Round)
                )
            }
    )
}

Thanks in advance!

Vivek Sharma

03/05/2021, 8:51 PM

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var state1 by remember { mutableStateOf(1) }
var state2 by remember { mutableStateOf(100 - state1) }

I am having kind of this code, I am updating

state1

and

state2 should update when state1 update

, but

state2 is not getting updated

, am I doing something wrong?

Mehdi Haghgoo

03/05/2021, 9:12 PM

I have a composable that is responsible to return a color in sequence from an array each time called. To make it work in sequence and remember what it returned last time, I added remember{mutableStateOf()}. I am using this composable to draw a group of boxes in another composable. The problem is the colors start to flicker in a scary way! Any idea why this happens?

boxes.mp4

yahyabayramoglu

03/05/2021, 9:20 PM

Is there an easy way to center a composable inside a

Card

? 😅 Card has fixed size, and it only contains a Text which needs to be centered. This is literally the only way I could get it work - I must be doing something wrong here 🙂

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Card(modifier = Modifier.size(50.dp).padding(4.dp)) {
    Row(verticalAlignment = Alignment.CenterVertically) {
          Text(
                text = "10",
                textAlign = TextAlign.Center,
                fontSize = 10.sp,
                modifier = Modifier.fillMaxWidth()
           )
     }
}

Law Gimenez

03/06/2021, 7:10 AM

I was going through the Jetpack Tutorial and it seems it wasn’t updated yet because I can’t seem to find

Modifier.preferredHeight(16.dp)

. So what is the fix for this?

Sudhir Singh Khanger

03/06/2021, 8:42 AM

I am not able to use

MaterialTheme.colors.onSurface

in a Composable. Cursor hover tells me

org.jetbrains.kotlin.diagnostics.SimpleDiagnostic@9406416a (error: could not render message)

whereas the build window tells me

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

But I am using it inside a Composable function.

Shivam Sethi

03/06/2021, 8:50 AM

Hello, what is the equivalent function of swifui view's on appear closure in compose, I want to perform certain action when composable appear on screen?

elye

03/06/2021, 10:45 AM

Anyone face this problem on the latest Jetpack Compose Beta? https://stackoverflow.com/questions/66504783/cannot-access-setcontent-it-is-internal-in-androidx-compose-ui-platform

Bradleycorn

03/06/2021, 2:22 PM

If I have a

Column

and I want it's content to be centered (vertically) on the screen, I can do:

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Column(modifier = Modifier.fillMaxSize(), verticalArrangement = Arrangement.Center) { ... }

But what if I don't want it centered vertically, but instead want (the top of) it to be offest 35% from the top of the screen? I can use the

offset

modifier (

offset(y=100.dp)

) to place it a certain amount from the top, but I want to specify the offset by percentage, not dp ...

jaqxues

03/06/2021, 5:01 PM

How can I animate switching from dark to light theme (without using animate on every single color on the theme)

Gabriel

03/06/2021, 7:21 PM

I have a

composeable

inside a

navhost

that takes an arg as part of it's route, I can get it as part of the arguments passed to the composable, but when I try to get it from the viewmodel inside a

@Composable

it's not present, https://gist.github.com/gabriel403/61c149a491e7701314b6a895e1a48df0

A. Sachdeva

03/06/2021, 7:53 PM

hi, i opened a new project and my editor seems to give no preview for any function. how can i fix this?

✅ 1

Shivam Sethi

03/06/2021, 10:19 PM

Does compose navigation support any animation/transition behavior while navigating ?

Rick Regan

03/07/2021, 12:40 AM

How do you get a

Button

to respond to both a press and a long press? I tried modifier

.pointerInput

with

detectTapGestures

and

onLongPress

but it does not detect the long press (or any of the other gestures). If I include a

Text

in the Button I can get the long press to work on the text portion, but I want to cover the whole button. (See code in thread.) Edit: I can't get

Modifier.combinedClickable

to do it either (see second code example in thread).

➕ 1

Konyaco

03/07/2021, 5:20 AM

https://issuetracker.google.com/181968398 Animation doesn't work when durationMillis >= 4295

Shivam Sethi

03/07/2021, 7:26 AM

any idea why I am not able to use Modifier.weight() modifier, it shows that in red

Olivier Patry

03/07/2021, 11:37 AM

I had an unexpected behavior, I'd consider it as a bug, but maybe there is a reason for that. Using the

BackdropScaffold

with a nullable front content. The front content is well displayed when not null, then when state is updated to

null

previous state remains.

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@Composable
fun AppScreen() {
    val viewModel = viewModel()
    val state by viewModel.state.observeAsState(null)

    BackdropScaffold(
        appBar = { },
        backLayerContent = {
            Column(
                Modifier.fillMaxWidth()
            ) {
                //
                Text("BACK")
            }
        },
        frontLayerContent = {
            state?.let { uiState ->
                Text("FRONT")
            }
        }
    )
}

To workaround this, I had to add an empty box:

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state?.let { uiState ->
    Text("FRONT")
} ?: Box {}

Is it expected? When the state is null at the beginning nothing is displayed as expected without the workaround.

Issa

03/07/2021, 11:56 AM

While taking the

Pathway

first code lab

Compose Basics

section

Animating your list

I have noticed that

LazyColumn

doesn’t remember the

isSelected

state of the item when recomposing. I have copy pasted the code from the

Pathway

and got the same results. Just when you scroll until the item is no more visible, when you scroll back the

isSelected

state is lost. IMO this is wrong cuz the state should be cached anyway and when recomposing the compiler should consider the previous state. Should I
Hoist
the state of the
Greeting
widget so I can manage it in the
LazyColumn
scope or this is just a Compose
Bug
? 🤔 Thanks in advance!

Slackbot

03/07/2021, 12:36 PM

This message was deleted.

Mjahangiry75

03/07/2021, 12:36 PM

hello everyone, I'm getting this error and I have no idea to fix it

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E/AndroidRuntime(21544): Process: co.newgates.speechtype, PID: 21544
E/AndroidRuntime(21544): java.lang.ArrayIndexOutOfBoundsException: length=5120; index=-2
E/AndroidRuntime(21544):        at androidx.compose.runtime.SlotTableKt.groupSize(SlotTable.kt:2558)
E/AndroidRuntime(21544):        at androidx.compose.runtime.SlotTableKt.access$groupSize(SlotTable.kt:1)
E/AndroidRuntime(21544):        at androidx.compose.runtime.SlotReader.groupSize(SlotTable.kt:596)
E/AndroidRuntime(21544):        at androidx.compose.runtime.ComposerImpl.recomposeToGroupEnd(Composer.kt:2215)
E/AndroidRuntime(21544):        at androidx.compose.runtime.ComposerImpl.skipCurrentGroup(Composer.kt:2499)
E/AndroidRuntime(21544):        at androidx.compose.runtime.ComposerImpl.recompose$runtime_release(Composer.kt:2625)
E/AndroidRuntime(21544):        at androidx.compose.runtime.CompositionImpl.recompose(Composition.kt:406)
E/AndroidRuntime(21544):        at androidx.compose.runtime.Recomposer.performRecompose(Recomposer.kt:724)
E/AndroidRuntime(21544):        at androidx.compose.runtime.Recomposer.access$performRecompose(Recomposer.kt:100)
E/AndroidRuntime(21544):        at androidx.compose.runtime.Recomposer$runRecomposeAndApplyChanges$2$2.invoke(Recomposer.kt:437)
E/AndroidRuntime(21544):        at androidx.compose.runtime.Recomposer$runRecomposeAndApplyChanges$2$2.invoke(Recomposer.kt:411)
E/AndroidRuntime(21544):        at androidx.compose.ui.platform.AndroidUiFrameClock$withFrameNanos$2$callback$1.doFrame(AndroidUiFrameClock.android.kt:34)
E/AndroidRuntime(21544):        at androidx.compose.ui.platform.AndroidUiDispatcher.performFrameDispatch(AndroidUiDispatcher.android.kt:112)
E/AndroidRuntime(21544):        at androidx.compose.ui.platform.AndroidUiDispatcher.access$performFrameDispatch(AndroidUiDispatcher.android.kt:43)
E/AndroidRuntime(21544):        at androidx.compose.ui.platform.AndroidUiDispatcher$dispatchCallback$1.doFrame(AndroidUiDispatcher.android.kt:72)
E/AndroidRuntime(21544):        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:765)
E/AndroidRuntime(21544):        at android.view.Choreographer.doCallbacks(Choreographer.java:580)
E/AndroidRuntime(21544):        at android.view.Choreographer.doFrame(Choreographer.java:549)
E/AndroidRuntime(21544):        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
E/AndroidRuntime(21544):        at android.os.Handler.handleCallback(Handler.java:739)
E/AndroidRuntime(21544):        at android.os.Handler.dispatchMessage(Handler.java:95)
E/AndroidRuntime(21544):        at android.os.Looper.loop(Looper.java:135)
E/AndroidRuntime(21544):        at android.app.ActivityThread.main(ActivityThread.java:5221)
E/AndroidRuntime(21544):        at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime(21544):        at java.lang.reflect.Method.invoke(Method.java:372)
E/AndroidRuntime(21544):        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
E/AndroidRuntime(21544):        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

🧵 1

florent

03/07/2021, 12:53 PM

Hi everyone, I did https://developer.android.com/codelabs/jetpack-compose-state?continue=https%3A%2F%2Fdev[…]2Fdeveloper.android.com%2Fcodelabs%2Fjetpack-compose-state yesterday and it doesn't work, I did the exercise step by step and also tried the finished version on my phone. When I try to edit and change the text, I can only type one letter, do you know how to fix that? Thanks!

msomu

03/07/2021, 2:08 PM

When I’m trying to use

AnimatedVisibility

I’m getting this error

org.jetbrains.kotlin.diagnostics.SimpleDiagnostic@4ae249ce (error: could not render message)

am I missing something? I have added these annotations

@ExperimentalAnimationApi

@OptIn(ExperimentalAnimationApi::class)

Can

03/07/2021, 3:04 PM

Hey people! I feel like I'm missing something here. I'd like to apply a Porterduffmode / BlendMode to a Text so that it changes the color so that the lower half is white for example. Previously this could be achieved with "drawText" and a Porterduffmode but DrawScope doesn't support drawText and I feel like i can't apply a ColorFilter to Text. There might be some way by writing a custom Painter and add a colorfilter to it but this doesn't feel like a straightforward way to do this. Any ideas?

Daniel

03/07/2021, 3:42 PM

The docs for

BlendMode.SrcIn

appear to be incorrect.

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Show the source image, but only where the two images overlap. 
The destination image is not rendered, it is treated merely as a mask. 
The color channels of the destination are ignored, only the opacity has an effect

The color channels of the destination are used. Assuming this just wraps the native equivalent, this would be the expected behavior. Asking here to check I'm not missing something stupid before I file a bug.

Piotr Prus

03/07/2021, 7:58 PM

I have this strange error that do not point to anything in my code and it crashes the app. I have Bottom Navigation, where one fragment (start destination) is 100% done in compose. When I start the app everything works fine, but when I go to other fragment and go back to my main (compose), I got this crash. Anyone saw something like this before?

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java.lang.NullPointerException: Attempt to invoke interface method 'void androidx.compose.runtime.MutableState.setValue(java.lang.Object)' on a null object reference
        at androidx.compose.ui.platform.AndroidComposeView.setLayoutDirection(AndroidComposeView.android.kt:930)
        at androidx.compose.ui.platform.AndroidComposeView.onRtlPropertiesChanged(AndroidComposeView.android.kt:768)
        at android.view.View.resolvePadding(View.java:20272)
        at android.view.ViewGroup.resolvePadding(ViewGroup.java:7765)
        at android.view.View.initializeScrollbarsInternal(View.java:6781)
        at android.view.View.<init>(View.java:6112)
        at android.view.ViewGroup.<init>(ViewGroup.java:697)
        at android.view.ViewGroup.<init>(ViewGroup.java:693)
        at android.view.ViewGroup.<init>(ViewGroup.java:689)
        at android.view.ViewGroup.<init>(ViewGroup.java:685)
        at androidx.compose.ui.platform.AndroidComposeView.<init>(AndroidComposeView.android.kt:115)
        at androidx.compose.ui.platform.Wrapper_androidKt.setContent(Wrapper.android.kt:79)
        at androidx.compose.ui.platform.AbstractComposeView.ensureCompositionCreated(ComposeView.android.kt:175)
        at androidx.compose.ui.platform.AbstractComposeView.onAttachedToWindow(ComposeView.android.kt:207)
        at android.view.View.dispatchAttachedToWindow(View.java:20479)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3489)
        at android.view.ViewGroup.addViewInner(ViewGroup.java:5278)
        at android.view.ViewGroup.addView(ViewGroup.java:5064)
        at androidx.fragment.app.FragmentContainerView.addView(FragmentContainerView.java:290)
        at android.view.ViewGroup.addView(ViewGroup.java:5004)
        at androidx.fragment.app.FragmentStateManager.addViewToContainer(FragmentStateManager.java:830)
        at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:520)
        at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:282)
        at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:2177)
        at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:2094)
        at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:1990)
        at androidx.fragment.app.FragmentManager$5.run(FragmentManager.java:524)
        at android.os.Handler.handleCallback(Handler.java:938)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:223)
        at android.app.ActivityThread.main(ActivityThread.java:7660)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)

Shivam Sethi

03/07/2021, 11:02 PM

What is the correct way of passing constructor arguments to compose view model using viewModel() in a composable?

👀 1

efemoney

03/07/2021, 11:02 PM

If I have a composable that is [0, 0, X, Y] size big and I wanted to clip it to display (and also report its size as) only a small part of that, how would I achieve that ? Say my composable reports its size as 100 x 100 but its children/content have a 500 x 500 canvas to draw on and I can select what area within that 500 x 500 canvas is visible in that 100 x 100 window 🤔

Alexjlockwood

03/08/2021, 1:53 AM

how can i get access to a given

Text

composable’s

ascent

and

descent

font metrics? there seems to be an API to access a text line’s

top

and

bottom

TextLayoutResult

, but nothing for

ascent

and

descent

https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:compose/[…]ult.kt;l=260-274;drc=75473ddf27998fdb2105416a5f0505f492ee8ad5 or is there a different API that i need to use? 🤔 cc @Siyamed