kotlinlang #compose

and when/how to use it. Does this seem like a valid use case: Using a Material theme, the designer provided direction for Outlined Buttons ... When a button is displayed on the surface or background color, it should use the Theme's

Secondary

color. When a button is displayed on another color, it should use that color's "on" Color. To achieve this, I wrote an

AppSurface

Composable that wraps a regular surface, and sets the value of a

LocalButtonColor

composition local, and then wrote a

AppOutlinedButton

Composable that wraps a regular OutlinedButton, and sets it's color using the

LocalButtonColor

... Does this seem like the right approach? (Code is posted in the thread)

Piotr Prus

03/04/2021, 9:41 PM

I do not know, if that is intended behaviour or bug, but detectGesture has change from alpha12 to beta01 for scrollable widgets. I have a BottomSheetScaffold, where bottomSheet is a

Column(modifier.verticalScroll)

, additionally I got a

.pointeInput

on it to detect when the dragGesture (scroll) actually happens. In alpha12, the dragGesture was detected on that column, but on Beta01, the

detectVerticalDrag

is never called. However , if the

.pointerInput

is called on child composable of that column, everything works fine. Is that a bug or intended behavior for scrollable columns? (Tested also for LazyColumns, which works exactly the same.

Arkadii Ivanov

03/04/2021, 9:48 PM

Is there a way to center content inside

Box

vertically, if the height of the

Box

is smaller than the height of the content? Currently it sticks to the top and is clipped at the bottom. But I want the content to be centered and clipped from top and bottom.

julioromano

03/04/2021, 10:30 PM

Box {
  One()
  Two()
}

I have 2 composables inside a

Box()

. I’d like the Box to set its size to the size of

One()

and I’d also like that

Two()

adapts its size to the size of

One()

. Is this possible?

Tristan

03/04/2021, 10:36 PM

Hello, I am having issues understanding how works arrangement in Jetpack Compose. I have 2 columns. I would the column on the right to take as much as needed, and the column on the left, to deal with the remaining space. In the remaining space, an image should be trying to take as much space as possible without compromising its aspect ratio. But I don’t find how to do it. Each time, the left column has more importance. This is the code I use at the moment,

Untitled

Sergey Y.

03/04/2021, 11:36 PM

How do I enable the new `experimental multithreaded recomposition`(yes, I am aware of the problems)? Leland said on the stream that it is now possible and you can turn it on and play. I'm reading the source for the

CompositionContext

class, but I don't know how to use it. Can anyone please help? Thanks 🙂

sen kumar

03/05/2021, 1:18 AM

In AnimatedVisibility the parent view get pushed upwards when I make them visible - How do I make the child view push downwards ?

Colton Idle

03/05/2021, 2:13 AM

Fun question to stir up the channel... At what point do we just use stackoverflow to make sure all of these great answers from the Android dev team (and others) are actually searchable? With compose beta, the api is now "stable" so should we start moving more questions there (and maybe post the questions here if they don't get traction?)

👍 1

tad

03/05/2021, 2:38 AM

Should

paddingFromBaseline(top = fontSize, bottom = lineHeight - fontSize)

be the default for Text? It's tough to match Figma/Sketch mocks without something that wraps Text to provide that modifier.

Vinay Gaba

03/05/2021, 3:30 AM

I’m curious about whether there is an API that allows me to get a callback about a composable being rendered on the screen or potentially modify a composable function right before its rendered. Sounds crazy I know but an API like

LayoutInflater.Factory2

gave some of this functionality in classic Android. Just curious if something like this already exists or is planned for in Compose.

Jason Inbody

03/05/2021, 4:32 AM

Did the Stack view get deprecated? Android studio isn't finding the import. I'm using compose beta01 btw. Edit: Oh looks like Box is now Stack

Landerl Young

03/05/2021, 9:22 AM

Does compose currently provide something like a AutoResizeText? If not how do implement one following the best practice? I currently came across same feature need, and what I did is like this:

var baseSize by remember { mutableStateOf(0f) }    
Column(
        modifier = modifier.onSizeChanged { (width, height) ->
            baseSize = min(width * 1.7f, height.toFloat())
        }
) {
        val firstLevelSize = baseSize * 5 / 10
        Text(
            fontSize = LocalDensity.current.run {
                firstLevelSize.toSp()
            },
           ...
        )
    }

Full code here: https://github.com/LanderlYoung/FlashAppSearch/blob/16a1fc9ac6c67e184f801e125f79ef[…]o/github/landerlyoung/flashappsearch/search/ui/piece/KeyIcon.kt But this code has a issue: during the initial composition the fontSize is 0, so the Text is not shown. when onSizeChanged got called, baseSize would update, and causing a second pass re-composition, at that time the Text is actually shown. Is there any better solutions? BTW, there is a StackOverFlow thread // https://stackoverflow.com/questions/63971569/androidautosizetexttype-in-jetpack-compose

Syex

03/05/2021, 9:31 AM

Hello, I have a

TextField

and a

Button

. Upon a click on the button I want to clear the focus from the

TextField

so the keyboard disappears. I'm currently trying

Button(
    onClick = {
        FocusRequester.Default.freeFocus()
    }
)

This crashes the app with

java.lang.IllegalStateException: FocusRequester is not initialized. One reason for this is that you requesting focus changes during composition. Focus requesters should not be made during composition, but should be made in response to some event.

Is there any other way to achieve this?

Simone Summo

03/05/2021, 9:50 AM

Hello, I am following this to implement navigation with bottomBar, now I want to open a child from a list that need to show full screen, I call it a modal, how can I achieve this behaviour? At the moment, using nested navigation, it opens inside the content space, with the bottom bar visible.

escodro

03/05/2021, 12:18 PM

Hello! 👋 I have a question regarding delegating Composables to inner nodes. Could someone help me? I have a

ModalBottomSheetLayout

that I want to appear on top of my

Scaffold

. The

Scaffold

has 4 tabs and I want each one to have a different content for this Modal. The solution I made is:

val (sheetContent, setSheetContent) = remember { mutableStateOf<@Composable () -> Unit>({}) }
AlkaaBottomSheetLayout(bottomSheetContent = currentSection) {
    Scaffold {
        when (tab) {
            HomeSection.Tasks -> TaskListSection(bottomSheetContent = setCurrentSection)
            HomeSection.Search -> SearchSection(bottomSheetContent = setCurrentSection)
            HomeSection.Categories -> CategoriesSection(bottomSheetContent = setCurrentSection)
            HomeSection.Settings -> SettingSection(bottomSheetContent = setCurrentSection)

Is it the correct way to delegate the composable function? Thanks a lot in advance! ❤️

FunkyMuse

03/05/2021, 12:22 PM

@OptIn(ExperimentalComposeUiApi::class)
@Composable
fun SearchInput(onInputText: (inputText: String) -> Unit = {}) {
    val keyboardController = LocalSoftwareKeyboardController.current
    var inputText by rememberSaveable { mutableStateOf("") }
    val invalidInput = inputText.isBlank()

    OutlinedTextField(
        modifier = Modifier
            .fillMaxWidth()
            .padding(start = 24.dp, end = 24.dp),
        isError = invalidInput,
        label = { Text(text = stringResource(id = R.string.search)) },
        value = inputText,
        onValueChange = { inputText = it },
        keyboardOptions = KeyboardOptions(
            KeyboardCapitalization.Words, autoCorrect = false,
            keyboardType = KeyboardType.Text, imeAction = ImeAction.Search
        ),
        keyboardActions = KeyboardActions(onSearch = {
            keyboardController?.hideSoftwareKeyboard()
            onInputText(inputText)
        })
    )
}

Hey guys, the code above crashes when the app goes into onPause/onStop the error is

java.lang.RuntimeException: Parcel: unable to marshal value androidx.compose.runtime.SnapshotMutableStateImpl@f5abce7

at android.os.Parcel.writeValue(Parcel.java:1926)

at android.os.Parcel.writeList(Parcel.java:1133)

at android.os.Parcel.writeValue(Parcel.java:1873)

at android.os.Parcel.writeMapInternal(Parcel.java:984)

at android.os.Parcel.writeMap(Parcel.java:966)

at android.os.Parcel.writeValue(Parcel.java:1838)

at android.os.Parcel.writeMapInternal(Parcel.java:984)

at android.os.Parcel.writeMap(Parcel.java:966)

at android.os.Parcel.writeValue(Parcel.java:1838)

at android.os.Parcel.writeList(Parcel.java:1133)

at android.os.Parcel.writeValue(Parcel.java:1873)

at android.os.Parcel.writeArrayMapInternal(Parcel.java:1016)

at android.os.BaseBundle.writeToParcelInner(BaseBundle.java:1620)

at android.os.Bundle.writeToParcel(Bundle.java:1303)

at android.os.Parcel.writeBundle(Parcel.java:1085)

at android.os.Parcel.writeValue(Parcel.java:1842)

at android.os.Parcel.writeArrayMapInternal(Parcel.java:1016)

at android.os.BaseBundle.writeToParcelInner(BaseBundle.java:1620)

at android.os.Bundle.writeToParcel(Bundle.java:1303)

at android.os.Parcel.writeBundle(Parcel.java:1085)

at android.os.Parcel.writeValue(Parcel.java:1842)

at android.os.BaseBundle.dumpStats(BaseBundle.java:1690)

at android.os.BaseBundle.dumpStats(BaseBundle.java:1727)

at android.app.servertransaction.PendingTransactionActions$StopInfo.run(PendingTransactionActions.java:150)

at android.os.Handler.handleCallback(Handler.java:938)

at android.os.Handler.dispatchMessage(Handler.java:99)

at android.os.Looper.loopOnce(Looper.java:201)

at android.os.Looper.loop(Looper.java:288)

at android.app.ActivityThread.main(ActivityThread.java:7729)

at java.lang.reflect.Method.invoke(Native Method)

at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)

at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:974)

if i use

var inputText by remember { mutableStateOf("") }

the issue goes away i've made the code by the Unidirectional data flow in Jetpack Compose documentation

:thread-please: 2

Pedro Gomez

03/05/2021, 12:37 PM

Hi all! Congrats for the first beta release 👏 I'm just wondering if we know when the beta02 release is going to be published. There is an ArrayOutOfBoundsException already reported on the issue tracker and fixed that I'm waiting for. Thanks!

Dominaezzz

03/05/2021, 12:45 PM

I'm using

Modifier.selectable(...)

and when the composable is clicked, the animation plays and UI is updated, but the composable doesn't stay selected (graphically speaking). Do I have to change the background colour myself?

Lilly

03/05/2021, 1:10 PM

Hi, what back button behavior would you guys expect with bottom navigation. Would you retain the history or always pop to the root tab? If we have for instance 3 tabs, would you expect A -> B -> C -> A -> B ; pressing back button: A -> C -> B -> A or would you expect A. Material Design doesn't cover this clearly and I read that google apps arent consistent here

Jorkoh

03/05/2021, 1:14 PM

This is a dumb one but how can I force the second element of a Row to have a minimum height equal to the height of the first element of that Row?

myanmarking

03/05/2021, 3:24 PM

what’s the replacement for Modifier.weight in latest version ?

Lukas K-G

03/05/2021, 3:27 PM

How would I capture DPad input in a composable function? 🤔

Rajashekar

03/05/2021, 3:40 PM

Does TextField allows us to specify max length of characters to enter? All I can see is it takes maxLines and singleLine. There is no support yet?

myanmarking

03/05/2021, 3:53 PM

@Composable
private fun PeopleScreen() {
    val viewModel: PeopleViewModel2 = viewModel()

    val viewState = viewModel.peopleList.collectAsState(initial = emptyList())
    val listItems: List<PeopleItem> by viewState

    LazyColumn(
        contentPadding = PaddingValues(horizontal = 8.dp, vertical = 16.dp),
        modifier = Modifier.padding(bottom = 56.dp)
            .fillMaxWidth()
    ) {
        for (item in listItem) {
            item(key = item.id) {
                PeopleItem(
                    item = item,
                    onFavouriteClicked = { viewModel.onFavouriteClicked(item) }
                )
                Spacer(modifier = Modifier.padding(bottom = 8.dp))
            }
        }
    }
}

zoha131

03/05/2021, 4:10 PM

i am struggling to use hilt with navigation-compose library. can anyone suggest any documentation or sample? actually i didn't found any documentation.

alorma

03/05/2021, 4:54 PM

How can i make a

IconButton

with elevation shadow?

alorma

03/05/2021, 5:10 PM

Another: Is there a way to check if a

Provider

is... provided? Ex: WindowInsets from accompanist, in a library, check if is provided by the main app and apply the

Modifier.statusBarPadding()

or else do nothing in the lib

Filip Wiesner

03/05/2021, 5:56 PM

Hello, I've been trying to implement paging with Paging 3 (both source and mediator) and Lazy column. Whenever I "scroll too fast" the app crashes with

IllegalArgumentException: Failed requirement

. The stacktrace points to

MeasureAndLayoutDelegate.kt:194

which is

require(!duringMeasureLayout)

. So my question is if I should look for some problem on my side or if it's likely a bug and I should create minimial repro and file an issue. Thanks for reply 🙏

Title

Filip Wiesner

03/05/2021, 5:56 PM

Hello, I've been trying to implement paging with Paging 3 (both source and mediator) and Lazy column. Whenever I "scroll too fast" the app crashes with

IllegalArgumentException: Failed requirement

. The stacktrace points to

MeasureAndLayoutDelegate.kt:194

which is

require(!duringMeasureLayout)

. So my question is if I should look for some problem on my side or if it's likely a bug and I should create minimial repro and file an issue. Thanks for reply 🙏

Dominaezzz

03/05/2021, 6:16 PM

It oddly looks like a race condition. I'd say minimal repro.

Andrey Kulikov

03/05/2021, 6:31 PM

Yes, please file a bug with a repro, it will help to find a fix

Filip Wiesner

03/05/2021, 8:58 PM

Ok, I'll see what I can do. Thanks 👌

Reported ✅ https://issuetracker.google.com/issues/182029524

View count: 2