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
hiring-french
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-español
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
panamá
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

Jacob Otto

04/21/2021, 8:10 AM
I am trying to figure out if there is a way to get the html code of a RenderContext extension function as string, instead of using it within the render context? I am using leaflet and this would be very handy to be able to write html in kotlin, even when there is plain html code as string required, e.g. for the leaflet div icons or tooltips.
j

Jan Weidenhaupt

04/21/2021, 9:47 AM
Hi, I take a quick look at the docs form leaflet and their API says, that you can provide a
HTMLElement
e.g. to their
divIcon
function. Did you try something similar to this?
// simulate external leaflet API
object L {
    fun <E: HTMLElement> divIcon(element: E) {
        // here leaflet can do everything with the given HTMLElement
        // e.g. appending text to the given HTMLElement
        element.appendChild(document.createTextNode("Hello World!"))
    }
}

// small wrapper Component to support fritz2 HTML DSL
fun RenderContext.divIcon(content: RenderContext.() -> Unit) {
    L.divIcon(div {
       content()
    }.domNode)
}

fun main() {
    // calling the wrapped leaflet component 
    // and using a fritz2 component inside
    render {
        divIcon {
            icon { fromTheme { fritz2 } }
        }
    }
}
In fritz2 all our standard HTML elements e.g.
div()
have the property
domNode
which gives you the corresponding native
HTMLElement
which external libraries like leaflet can use. I hope I get your right and my approach work for you. If not please let me know 😉
j

Jacob Otto

04/21/2021, 11:49 AM
Thanks a lot. I will try that out. :)
Tried to make it work, but unfortunately it is not quite what I was looking for. At least from my understanding. I don't want to call the leaflet divIcon function in the RenderContext, but I want to pass a function that uses the fritz2 DSL to the leaflet divIcon() JS function. Therefore, I would like to convert a function like this:
fun RenderContext.test(){
    icon { fromTheme { fritz2 } }
}
to a HTMLElement, so that I can use it in the leaflet context like this:
L.marker(...).setIcon( L.divIcon( test() ) )
I created a kotlin data class for the leaflet DivIcon to be able to easily handle all the icon options dynamically in my webapp and then I create a JS object out of it to display it with leaflet. Currently my data class has a string containing the html code and this would be nice to change to HTMLElement and use a fritz2 DSL there. I dont know if I am making it overcomplicated, but that is my current setup to deal with the kotlin <-> JS handover.
j

Jan Weidenhaupt

04/23/2021, 12:38 PM
Ok, now I get you. Currently you can try this approach:
fun RenderContext.stringify(content: RenderContext.() -> Unit): String {
    return Div(job = this.job).apply {
        content()
    }.domNode.innerHTML
}

fun main() {
    render {
        pre {
            +stringify {
               icon { fromTheme { fritz2 } }
            }
        }
    }
}
You need to create a wrapper function (like
test()
). You can then use the fritz2 components functions inside the
content
parameter. Internally a
Div()
gets created to get access to the underlying
domNode
and
innerHTML
which presents the HTML generated by the fritz2 component (here
icon()
). I hope that helps 😉
j

Jacob Otto

04/27/2021, 4:57 PM
Thanks a lot! This works great. I changed it a bit and ended up using:
fun stringify(content: RenderContext.() -> Unit): String {
    return Div(job = Job(parent = null)).apply {
        content()
    }.domNode.innerHTML
}
This allows me to use the string everywhere, also outside the RenderContext. 🙂 Does that make sense or is it not ideal to define the job like this without parent?
j

Jan Weidenhaupt

04/27/2021, 5:13 PM
Yes, I thougt about it, but I think if you don't face troubles, it should work well to create a new
Job()
everytime you call
stringify()
function. Instead of a
String
you can also use the
domNode
directly. This should be more performant ;)
j

Jacob Otto

04/27/2021, 5:22 PM
Indeed, I mentioned some performance issues with a bigger amout of markers I am creating with this. I thought it relates to the svg icons I am using instead of icon-font icons, but this could be related to the amount of Job() creations... I will try to use the domnode and maybe figure something out to handover an existing job, instead of creating a new one.