SideBySideNavigator.kt

import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.ProvidableCompositionLocal
import androidx.compose.runtime.remember
import androidx.compose.runtime.staticCompositionLocalOf
import androidx.compose.ui.Modifier
import cafe.adriel.voyager.core.annotation.ExperimentalVoyagerApi
import cafe.adriel.voyager.core.lifecycle.DisposableEffectIgnoringConfiguration
import cafe.adriel.voyager.core.screen.Screen
import cafe.adriel.voyager.core.stack.previousItem
import cafe.adriel.voyager.navigator.Navigator
import cafe.adriel.voyager.navigator.NavigatorDisposeBehavior
import cafe.adriel.voyager.navigator.compositionUniqueId
import cafe.adriel.voyager.navigator.tab.CurrentTab
import cafe.adriel.voyager.navigator.tab.Tab

public val LocalSideBySideNavigator: ProvidableCompositionLocal<SideBySideNavigator> =
    staticCompositionLocalOf { error("SideBySide not initialized") }

@Composable
public fun SideBySideNavigator(
    screen: Screen,
    key: String = compositionUniqueId(),
    content: @Composable (SideBySideNavigator) -> Unit = { CurrentSideBySideScreen() },
) {
    Navigator(
        screen = screen,
        disposeBehavior = NavigatorDisposeBehavior(
            disposeSteps = false
        ),
        onBackPressed = null,
        key = key,
    ) { navigator ->
        val sideBySideNavigator = remember(navigator) {
            SideBySideNavigator(navigator)
        }

        CompositionLocalProvider(LocalSideBySideNavigator provides sideBySideNavigator) {
            content(sideBySideNavigator)
        }
    }
}

public class SideBySideNavigator internal constructor(
    internal val navigator: Navigator
) {

    val left: Screen? get() = navigator.previousItem
    val right: Screen get() = navigator.lastItem

    @Composable
    public fun saveableState(
        key: String,
        screen: Screen,
        content: @Composable () -> Unit
    ) {
        navigator.saveableState(key, screen, content)
    }
}

@Composable
public fun CurrentSideBySideScreen() {
    val sideBySideNavigator = LocalSideBySideNavigator.current
    val leftScreen = sideBySideNavigator.left
    val rightScreen = sideBySideNavigator.right

    Row(
        modifier = Modifier.fillMaxWidth(),
    ) {
        if(leftScreen != null) {
            Box(modifier = Modifier.weight(1f)) {
                sideBySideNavigator.saveableState("sidebyside", leftScreen) {
                    leftScreen.Content()
                }

            }
        }

        Box(modifier = Modifier.weight(1f)) {
            sideBySideNavigator.saveableState("sidebyside", rightScreen) {
                rightScreen.Content()
            }
        }
    }
}

Eu imagino que um comportamento aceitavel desse seria parecido com um discord, barra lateral esquerda e conteudo na direita