12 KiB
Desktop components
What is covered
In this tutorial, we will show you how to use desktop-specific components of Compose for Desktop such as scrollbars and tooltips.
Scrollbars
You can apply scrollbars to scrollable components. The scrollbar and scrollable components share a common state to synchronize with each other. For example, VerticalScrollbar
can be attached to Modifier.verticalScroll
, and LazyColumnFor
and HorizontalScrollbar
can be attached to Modifier.horizontalScroll
and LazyRowFor
.
import androidx.compose.foundation.HorizontalScrollbar
import androidx.compose.foundation.VerticalScrollbar
import androidx.compose.foundation.background
import androidx.compose.foundation.horizontalScroll
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.Spacer
import androidx.compose.foundation.layout.fillMaxHeight
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.rememberScrollbarAdapter
import androidx.compose.foundation.verticalScroll
import androidx.compose.material.Text
import androidx.compose.runtime.Composable
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp
import androidx.compose.ui.window.WindowState
import androidx.compose.ui.window.singleWindowApplication
fun main() = singleWindowApplication(
title = "Scrollbars",
state = WindowState(width = 250.dp, height = 400.dp)
) {
Box(
modifier = Modifier.fillMaxSize()
.background(color = Color(180, 180, 180))
.padding(10.dp)
) {
val stateVertical = rememberScrollState(0)
val stateHorizontal = rememberScrollState(0)
Box(
modifier = Modifier
.fillMaxSize()
.verticalScroll(stateVertical)
.padding(end = 12.dp, bottom = 12.dp)
.horizontalScroll(stateHorizontal)
) {
Column {
for (item in 0..30) {
TextBox("Item #$item")
if (item < 30) {
Spacer(modifier = Modifier.height(5.dp))
}
}
}
}
VerticalScrollbar(
modifier = Modifier.align(Alignment.CenterEnd)
.fillMaxHeight(),
adapter = rememberScrollbarAdapter(stateVertical)
)
HorizontalScrollbar(
modifier = Modifier.align(Alignment.BottomStart)
.fillMaxWidth()
.padding(end = 12.dp),
adapter = rememberScrollbarAdapter(stateHorizontal)
)
}
}
@Composable
fun TextBox(text: String = "Item") {
Box(
modifier = Modifier.height(32.dp)
.width(400.dp)
.background(color = Color(200, 0, 0, 20))
.padding(start = 10.dp),
contentAlignment = Alignment.CenterStart
) {
Text(text = text)
}
}
![Scrollbars](/github/compose-jb/media/commit/38e3db13a238c396fa1e700647bbc2190af3ba99/tutorials/Desktop_Components/scrollbars.gif)
Lazy scrollable components with Scrollbar
You can use scrollbars with lazy scrollable components, for example, LazyColumn
.
import androidx.compose.foundation.VerticalScrollbar
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Spacer
import androidx.compose.foundation.layout.fillMaxHeight
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.lazy.LazyColumn
import androidx.compose.foundation.lazy.rememberLazyListState
import androidx.compose.foundation.rememberScrollbarAdapter
import androidx.compose.material.Text
import androidx.compose.runtime.Composable
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp
import androidx.compose.ui.window.Window
import androidx.compose.ui.window.application
import androidx.compose.ui.window.rememberWindowState
fun main() = application {
Window(
onCloseRequest = ::exitApplication,
title = "Scrollbars",
state = rememberWindowState(width = 250.dp, height = 400.dp)
) {
LazyScrollable()
}
}
@Composable
fun LazyScrollable() {
Box(
modifier = Modifier.fillMaxSize()
.background(color = Color(180, 180, 180))
.padding(10.dp)
) {
val state = rememberLazyListState()
LazyColumn(Modifier.fillMaxSize().padding(end = 12.dp), state) {
items(1000) { x ->
TextBox("Item #$x")
Spacer(modifier = Modifier.height(5.dp))
}
}
VerticalScrollbar(
modifier = Modifier.align(Alignment.CenterEnd).fillMaxHeight(),
adapter = rememberScrollbarAdapter(
scrollState = state
)
)
}
}
@Composable
fun TextBox(text: String = "Item") {
Box(
modifier = Modifier.height(32.dp)
.fillMaxWidth()
.background(color = Color(0, 0, 0, 20))
.padding(start = 10.dp),
contentAlignment = Alignment.CenterStart
) {
Text(text = text)
}
}
![Lazy component](/github/compose-jb/media/commit/38e3db13a238c396fa1e700647bbc2190af3ba99/tutorials/Desktop_Components/lazy_scrollbar.gif)
Theme applying
Scrollbars support themes to change their appearance. The example below shows how to use the DesktopMaterialTheme
appearance for the scrollbar.
import androidx.compose.desktop.DesktopMaterialTheme
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.fillMaxHeight
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.Spacer
import androidx.compose.foundation.rememberScrollbarAdapter
import androidx.compose.foundation.rememberScrollState
import androidx.compose.material.Text
import androidx.compose.foundation.VerticalScrollbar
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.verticalScroll
import androidx.compose.runtime.Composable
import androidx.compose.ui.Alignment
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import androidx.compose.ui.window.Window
import androidx.compose.ui.window.application
import androidx.compose.ui.window.rememberWindowState
fun main() = application {
Window(
onCloseRequest = ::exitApplication,
title = "Scrollbars",
state = rememberWindowState(width = 250.dp, height = 400.dp)
) {
DesktopMaterialTheme {
Box(
modifier = Modifier.fillMaxSize()
.background(color = Color(180, 180, 180))
.padding(10.dp)
) {
val state = rememberScrollState(0)
Column(
modifier = Modifier
.verticalScroll(state)
.fillMaxSize()
.padding(end = 12.dp)
) {
for (item in 0..30) {
TextBox("Item #$item")
if (item < 30) {
Spacer(modifier = Modifier.height(5.dp))
}
}
}
VerticalScrollbar(
modifier = Modifier.align(Alignment.CenterEnd)
.fillMaxHeight(),
adapter = rememberScrollbarAdapter(state)
)
}
}
}
}
@Composable
fun TextBox(text: String = "Item") {
Box(
modifier = Modifier.height(32.dp)
.fillMaxWidth()
.background(color = Color(0, 0, 0, 20))
.padding(start = 10.dp),
contentAlignment = Alignment.CenterStart
) {
Text(text = text)
}
}
![Themed scrollbar](/github/compose-jb/media/commit/38e3db13a238c396fa1e700647bbc2190af3ba99/tutorials/Desktop_Components/themed_scrollbar.gif)
Tooltips
You can add tooltip to any components using BoxWithTooltip
. Basically BoxWithTooltip
is a Box
with the ability to show a tooltip, and has the same arguments and behavior as Box
.
The main arguments of the BoxWithTooltip
function:
- tooltip - composable content representing tooltip
- tooltipPlacement - describes how to place tooltip. You can specify an anchor (the mouse cursor or the component), an offset and an alignment
- delay - time delay in milliseconds after which the tooltip will be shown (default is 500 ms)
import androidx.compose.foundation.BoxWithTooltip
import androidx.compose.foundation.TooltipPlacement
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material.Button
import androidx.compose.material.Surface
import androidx.compose.material.Text
import androidx.compose.ui.Alignment
import androidx.compose.ui.ExperimentalComposeUiApi
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.shadow
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.DpOffset
import androidx.compose.ui.unit.dp
import androidx.compose.ui.window.Window
import androidx.compose.ui.window.application
import androidx.compose.ui.window.rememberWindowState
@OptIn(ExperimentalComposeUiApi::class)
fun main() = application {
Window(
onCloseRequest = ::exitApplication,
title = "Tooltip Example",
state = rememberWindowState(width = 300.dp, height = 300.dp)
) {
val buttons = listOf("Button A", "Button B", "Button C", "Button D", "Button E", "Button F")
Column(Modifier.fillMaxSize(), Arrangement.spacedBy(5.dp)) {
buttons.forEachIndexed { index, name ->
// wrap button in BoxWithTooltip
BoxWithTooltip(
modifier = Modifier.padding(start = 40.dp),
tooltip = {
// composable tooltip content
Surface(
modifier = Modifier.shadow(4.dp),
color = Color(255, 255, 210),
shape = RoundedCornerShape(4.dp)
) {
Text(
text = "Tooltip for ${name}",
modifier = Modifier.padding(10.dp)
)
}
},
delay = 600, // in milliseconds
tooltipPlacement = TooltipPlacement.CursorPoint(
alignment = Alignment.BottomEnd,
offset = if (index % 2 == 0) DpOffset(-16.dp, 0.dp) else DpOffset.Zero // tooltip offset
)
) {
Button(onClick = {}) { Text(text = name) }
}
}
}
}
}
![Tooltip](/github/compose-jb/media/commit/38e3db13a238c396fa1e700647bbc2190af3ba99/tutorials/Desktop_Components/tooltips.gif)