CompositionLocalAccessorScope

Known direct subclasses
StyleScope

A StyleScope is the receiver scope of a Style lambda.

Summary

Public properties
T

An extension property that allows accessing the current value of a composition local in the context of this scope.
Cmn

Extension functions
inline Boolean

Evaluates a boolean query against the current UiMediaScope from a CompositionLocalAccessorScope.
Cmn

Public properties

currentValue

Cmn 
val CompositionLocal<T>.currentValue: T

An extension property that allows accessing the current value of a composition local in the context of this scope. This scope is the type of the this parameter when in a computed composition. Computed composition locals can be provided by either using compositionLocalWithComputedDefaultOf or by using the ProvidableCompositionLocal.providesComputed infix operator.

import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.compositionLocalOf

val LocalValue = compositionLocalOf { 10 }
val LocalLargerValue = compositionLocalOf { 12 }

@Composable
fun App() {
    CompositionLocalProvider(
        LocalLargerValue providesComputed { LocalValue.currentValue + 10 }
    ) {
        SomeScreen()
    }
}
See also
ProvidableCompositionLocal
providesComputed
provides
CompositionLocalProvider

Extension functions

mediaQuery

Cmn 
@ExperimentalMediaQueryApi
inline fun CompositionLocalAccessorScope.mediaQuery(query: UiMediaScope.() -> Boolean): Boolean

Evaluates a boolean query against the current UiMediaScope from a CompositionLocalAccessorScope.

If called within a snapshot-aware context, the specific property reads within the query will be tracked, and the scope will be invalidated when any of those properties change.

import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.interaction.MutableInteractionSource
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.style.MutableStyleState
import androidx.compose.foundation.style.Style
import androidx.compose.foundation.style.hovered
import androidx.compose.foundation.style.pressed
import androidx.compose.foundation.style.styleable
import androidx.compose.runtime.Composable
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.UiMediaScope.PointerPrecision
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.mediaQuery
import androidx.compose.ui.unit.dp

// Create a styleable clickable box
@Composable
fun ClickableStyleableBox(
    onClick: () -> Unit,
    modifier: Modifier = Modifier,
    style: Style = Style,
) {
    val interactionSource = remember { MutableInteractionSource() }
    val styleState = remember { MutableStyleState(interactionSource) }
    Box(
        modifier =
            modifier
                .clickable(interactionSource = interactionSource, onClick = onClick)
                .styleable(styleState, style)
    )
}

ClickableStyleableBox(
    onClick = {},
    style = {
        background(Color.Green)

        // Dynamic size based on window Size
        if (mediaQuery { windowWidth > 600.dp && windowHeight > 400.dp }) {
            size(200.dp)
        } else {
            size(150.dp)
        }

        // Hover state for fine pointer input
        if (mediaQuery { pointerPrecision == PointerPrecision.Fine }) {
            hovered { background(Color.Yellow) }
        }
        pressed { background(Color.Red) }
    },
)
Parameters
query: UiMediaScope.() -> Boolean

A lambda expression with UiMediaScope as its receiver, representing the condition to check.
Returns
Boolean

The immediate boolean result of the query.