https://kotlinlang.org logo
Channels
100daysofcode
100daysofkotlin
100daysofkotlin-2021
advent-of-code
aem
ai
alexa
algeria
algolialibraries
amsterdam
android
android-architecture
android-databinding
android-studio
androidgithubprojects
androidthings
androidx
androidx-xprocessing
anime
anko
announcements
apollo-kotlin
appintro
arabic
argentina
arkenv
arksemdevteam
armenia
arrow
arrow-contributors
arrow-meta
ass
atlanta
atm17
atrium
austin
australia
austria
awesome-kotlin
ballast
bangladesh
barcelona
bayarea
bazel
beepiz-libraries
belgium
benchmarks
berlin
big-data
books
boston
brazil
brikk
budapest
build
build-tools
bulgaria
bydgoszcz
cambodia
canada
carrat
carrat-dev
carrat-feed
chicago
chile
china
chucker
cincinnati-user-group
cli
clikt
cloudfoundry
cn
cobalt
code-coverage
codeforces
codemash-precompiler
codereview
codingame
codingconventions
coimbatore
collaborations
colombia
colorado
communities
competitive-programming
competitivecoding
compiler
compose
compose-android
compose-desktop
compose-hiring
compose-ios
compose-mp
compose-ui-showcase
compose-wear
compose-web
confetti
connect-audit-events
corda
cork
coroutines
couchbase
coursera
croatia
cryptography
cscenter-course-2016
cucumber-bdd
cyprus
czech
dagger
data2viz
databinding
datascience
dckotlin
debugging
decompose
decouple
denmark
deprecated
detekt
detekt-hint
dev-core
dfw
docs-revamped
dokka
domain-driven-design
doodle
dsl
dublin
dutch
eap
eclipse
ecuador
edinburgh
education
effective-kotlin
effectivekotlin
emacs
embedded-kotlin
estatik
event21-community-content
events
exposed
failgood
fb-internal-demo
feed
firebase
flow
fluid-libraries
forkhandles
forum
fosdem
fp-in-kotlin
framework-elide
freenode
french
fritz2
fuchsia
functional
funktionale
gamedev
ge-kotlin
general-advice
georgia
geospatial
german-lang
getting-started
github-workflows-kt
glance
godot-kotlin
google-io
gradle
graphic
graphkool
graphql
graphql-kotlin
graviton-browser
greece
grpc
gsoc
gui
hackathons
hacktoberfest
hamburg
hamkrest
helios
helsinki
hexagon
hibernate
hikari-cp
hire-me
hiring
hongkong
hoplite
http4k
hungary
hyderabad
image-processing
india
indonesia
inkremental
intellij
intellij-plugins
intellij-tricks
internships
introduce-yourself
io
ios
iran
israel
istanbulcoders
italian
jackson-kotlin
jadx
japanese
jasync-sql
java-to-kotlin-refactoring
javadevelopers
javafx
javalin
javascript
jdbi
jhipster-kotlin
jobsworldwide
jpa
jshdq
juul-libraries
jvm-ir-backend-feedback
jxadapter
k2-early-adopters
kaal
kafka
kakao
kalasim
kapt
karachi
karg
karlsruhe
kash_shell
kaskade
kbuild
kdbc
kgen-doc-tools
kgraphql
kinta
klaxon
klock
kloudformation
kmdc
kmm-espaƱol
kmongo
knbt
knote
koalaql
koans
kobalt
kobweb
kodein
kodex
kohesive
koin
koin-dev
komapper
kondor-json
kong
kontent
kontributors
korau
korean
korge
korim
korio
korlibs
korte
kotest
kotest-contributors
kotless
kotlick
kotlin-asia
kotlin-beam
kotlin-by-example
kotlin-csv
kotlin-data-storage
kotlin-foundation
kotlin-fuel
kotlin-in-action
kotlin-inject
kotlin-latam
kotlin-logging
kotlin-multiplatform-contest
kotlin-mumbai
kotlin-native
kotlin-pakistan
kotlin-plugin
kotlin-pune
kotlin-roadmap
kotlin-samples
kotlin-sap
kotlin-serbia
kotlin-spark
kotlin-szeged
kotlin-website
kotlinacademy
kotlinbot
kotlinconf
kotlindl
kotlinforbeginners
kotlingforbeginners
kotlinlondon
kotlinmad
kotlinprogrammers
kotlinsu
kotlintest
kotlintest-devs
kotlintlv
kotlinultimatechallenge
kotlinx-datetime
kotlinx-files
kotlinx-html
kotrix
kotson
kovenant
kprompt
kraph
krawler
kroto-plus
ksp
ktcc
ktfmt
ktlint
ktor
ktp
kubed
kug-leads
kug-torino
kvision
kweb
lambdaworld_cadiz
lanark
language-evolution
language-proposals
latvia
leakcanary
leedskotlinusergroup
lets-have-fun
libgdx
libkgd
library-development
lincheck
linkeddata
lithuania
london
losangeles
lottie
love
lychee
macedonia
machinelearningbawas
madrid
malaysia
mathematics
meetkotlin
memes
meta
metro-detroit
mexico
miami
micronaut
minnesota
minutest
mirror
mockk
moko
moldova
monsterpuzzle
montreal
moonbean
morocco
motionlayout
mpapt
mu
multiplatform
mumbai
munich
mvikotlin
mvrx
myndocs-oauth2-server
naming
navigation-architecture-component
nepal
new-mexico
new-zealand
newname
nigeria
nodejs
norway
npm-publish
nyc
oceania
ohio-kotlin-users
oldenburg
oolong
opensource
orbit-mvi
osgi
otpisani
package-search
pakistan
panamĆ”
pattern-matching
pbandk
pdx
peru
philippines
phoenix
pinoy
pocketgitclient
polish
popkorn
portugal
practical-functional-programming
proguard
prozis-android-backup
pyhsikal
python
python-contributors
quasar
random
re
react
reaktive
realm
realworldkotlin
reductor
reduks
redux
redux-kotlin
refactoring-to-kotlin
reflect
refreshversions
reports
result
rethink
revolver
rhein-main
rocksdb
romania
room
rpi-pico
rsocket
russian
russian_feed
russian-kotlinasfirst
rx
rxjava
san-diego
science
scotland
scrcast
scrimage
script
scripting
seattle
serialization
server
sg-user-group
singapore
skia-wasm-interop-temp
skrape-it
slovak
snake
sofl-user-group
southafrica
spacemacs
spain
spanish
speaking
spek
spin
splitties
spotify-mobius
spring
spring-security
squarelibraries
stackoverflow
stacks
stayhungrystayfoolish
stdlib
stlouis
strife-discord-lib
strikt
students
stuttgart
sudan
swagger-gradle-codegen
swarm
sweden
swing
swiss-user-group
switzerland
talking-kotlin
tallinn
tampa
teamcity
tegal
tempe
tensorflow
terminal
test
testing
testtestest
texas
tgbotapi
thailand
tornadofx
touchlab-tools
training
tricity-kotlin-user-group
trójmiasto
truth
tunisia
turkey
turkiye
twitter-feed
uae
udacityindia
uk
ukrainian
uniflow
unkonf
uruguay
utah
uuid
vancouver
vankotlin
vertx
videos
vienna
vietnam
vim
vkug
vuejs
web-mpp
webassembly
webrtc
wimix_sentry
wwdc
zircon
Powered by
Title
j

Joe Altidore

04/28/2023, 12:52 PM
Hello guys I am using a Layout composable to implement Animated drawer but whenever I set the background of the Layout to Transparent it become Black instead.
Layout(
    modifier = modifier.background(Colors.Transparent),
    content = {
        drawerContents()
        content()
    }
)
But if i provide other colors, they are applied. How do i work around this. Thanks
t

Travis

04/28/2023, 6:51 PM
You could just not include a background to the layout when the color would be transparent, right? I'm assuming your colors are variable, so this would look something like
@Composable
fun MyLayout(
    drawerContents: @Composable () -> Unit,
    modifier: Modifier = Modifier, 
    backgroundColor: Color = Color.Transparent,
    content: @Composable () -> Unit,
) {
  val backgroundModifier = 
      if(backgroundColor != Color.Transparent) Modifier.background(backgroundColor) 
      else Modifier
  Layout(
      modifier = modifier.then(backgroundModifier),
      content = {
          drawerContents()
          content()
      }
  )
}
j

Joe Altidore

04/28/2023, 6:53 PM
I tried that but omitting the background still has that background on it
t

Travis

04/28/2023, 6:58 PM
Presumably you have some content behind this layout you want to see through it. Are you doing something like putting a GLSurfaceView inside it or something like that? Some wacky canvas stuff like transparent paint on hardware layers?
j

Joe Altidore

04/28/2023, 7:01 PM
I am using the layout for animate drawer. It's content is a BottomSheetScaffold whose shape is rounded at the top. However, the background color is making the bottom sheet look weird. I modified my background color in themes to transparent and now the color is white
t

Travis

04/28/2023, 8:10 PM
Oh! That's probably something the scaffold is doing. Yep, there it is - backgroundColor in BottomSheetScaffold is the MaterialTheme.colors.background. You should pass Transparent in there too
Basically the
content()
block of your layout contains the background color you're seeing. Though that wouldn't explain why a Modifier.background on the Layout with, say, Color.Blue would show up blue, since your scaffold should cover that up too.
j

Joe Altidore

04/28/2023, 9:19 PM
I have set the Scaffold background to Transparent as well
t

Travis

04/28/2023, 9:20 PM
And is there anything behind the Layout?
j

Joe Altidore

04/28/2023, 9:25 PM
The content of the BottomSheet is a Google map and a NavHost
t

Travis

04/28/2023, 9:27 PM
MapView uses a GL surface, right? That sort of thing can result in black if it's covered up and it thinks it doesn't have to draw. We had a similar issue on a camera feed app I worked with. The easiest solution to something like that is to move the stuff that's "underneath" your layout into it as part of the content. The scaffold stuff typically kind of assumes it's at the root of your app anyway
One test you can run to see if this is the issue is to wrap the whole thing in a frame layout and put a magenta box at the center between the compose view and the background view. If you see the box the problem is the map. If you don't it really is the compose layer and a layout inspector might do you more good than I have šŸ˜•
j

Joe Altidore

04/28/2023, 9:43 PM
I don't understand
Let me share a snippet of my code so you'll see
@Composable
fun MyLayout(
    modifier: Modifier,
    state: AnimatedDrawerState = rememberAnimatedDrawerState(
        drawerWidth = 280.dp,
    ),
    drawer: @Composable ()  -> Unit,
    bottomSheetScaffold: @Composable () -> Unit
) {
    Layout(
        modifier = modifier,
        content = {
            drawer()
            bottomSheetScaffold()
        }
    ) { measurables, constraints ->
        val (drawerContentMeasurable, contentMeasurable) = measurables
        val drawerContentConstraints = Constraints.fixed(
            width = state.drawerWidth.coerceAtMost(constraints.maxWidth.toFloat()).toInt(),
            height = constraints.maxHeight,
        )
        val drawerContentPlaceable = drawerContentMeasurable.measure(drawerContentConstraints)
        val contentConstraints = Constraints.fixed(
            width = constraints.maxWidth,
            height = constraints.maxHeight,
        )
        val contentPlaceable = contentMeasurable.measure(contentConstraints)
        layout(
            width = constraints.maxWidth,
            height = constraints.maxHeight,
        ) {
            contentPlaceable.placeRelativeWithLayer(
                IntOffset.Zero,
            ) {
                transformOrigin = state.contentTransformOrigin
                scaleX = state.contentScaleX
                scaleY = state.contentScaleY
                translationX = state.contentTranslationX
            }
            drawerContentPlaceable.placeRelativeWithLayer(
                IntOffset.Zero,
            ) {
                translationX = state.drawerTranslationX
                shadowElevation = state.drawerElevation
            }
        }
    }
}
This is my layout
and this is how I am using it with the BottomSheetScaffold
@OptIn(ExperimentalMaterialApi::class)
@Composable
fun MyIndex(
    modifier: Modifier = Modifier,
    peekHeight: Float
) {
    val sheetPeekHeight by animateDpAsState(
        targetValue = peekHeight.dp,
        animationSpec = spring(stiffness = Spring.StiffnessLow)
    )

    val animation = remember { Animatable(0f) }
    val drawerState = rememberAnimatedDrawerState(
        drawerWidth = (LocalConfiguration.current.screenWidthDp - 68).dp ,
        animation
    )
    val scope = rememberCoroutineScope()
    val scaffoldState = rememberBottomSheetScaffoldState(
        bottomSheetState = rememberBottomSheetState(initialValue = BottomSheetValue.Collapsed),
    )
    MyLayout(
        modifier = modifier,
        state = drawerState,
        drawer = {
        //Drawer Content
        }
    ) {
        BottomSheetScaffold(
            sheetContent = {
                //Sheet content
            },
            sheetShape = RoundedCornerShape(topStart = 24.dp, topEnd = 24.dp),
            sheetPeekHeight = sheetPeekHeight,
            scaffoldState = scaffoldState

        ) {
            AndroidView(
                factory = {context ->
                    MapView(context).apply {
                        onCreate(null)
                        onResume()
                        getMapAsync {

                        }
                    }
                },
                modifier = modifier.background(Color.Transparent),
            )

            NavHost(
                navController = rememberNavController(),
                startDestination = "start_route",
                modifier = modifier.background(Color.Yellow)
            ){
                //My Routes Here
            }
        }
    }
}
t

Travis

05/01/2023, 10:15 PM
So you're passing Modifier.background(Color.Transparent) to MyIndex and you're seeing black? Is there anything behind MyIndex? Like is that the root of the UI hierarchy? Or is it in a box with something behind it? The background you pass to MyLayout should only cover up anything outside the scope of MyIndex. That is, if you had a Box with two elements: A list of to-do tasks and MyIndex. In that case the background of MyIndex would cover up your to-do list via the MyLayout modifier. But if the root of your app is MyIndex then you'd expect a black background if the index bg is transparent because that's just the default background for an empty app.
To clarify - The MapView inside the AndroidView is inside the content of MyLayout. This means that a background on MyLayout would have no effect on the mapview because it'd show up behind the MapView.