Compose Custom Layout: row of components, all made as wide as the widest one

EqualWidthComponentsRow.kt

/*
 * ----------------------------------------------------------------------------
 * "THE BEER-WARE LICENSE" (Revision 42):
 * Sebastiano Poggi wrote this file.  As long as you retain this notice you
 * can do whatever you want with this stuff. If we meet some day, and you think
 * this stuff is worth it, you can buy me a beer in return.   Seb
 * ----------------------------------------------------------------------------
 */

package dev.sebastiano.bundel

import androidx.compose.foundation.border
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.material3.Button
import androidx.compose.material3.Surface
import androidx.compose.material3.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.layout.Layout
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.Constraints
import androidx.compose.ui.unit.dp
import kotlin.math.roundToInt

@Preview
@Composable
fun EqualWidthComponentsRow() {
    Surface(Modifier.fillMaxSize()) {
        Column(
            verticalArrangement = Arrangement.spacedBy(16.dp),
            horizontalAlignment = Alignment.CenterHorizontally,
            modifier = Modifier.padding(16.dp)
        ) {
            Layout(
                modifier = Modifier.border(1.dp, Color.Red),
                content = {
                    Button(onClick = { }) {
                        Text("First button")
                    }

                    Button(onClick = { }) {
                        Text("Second")
                    }
                }
            ) { measurables, constraints ->
                val hGapWidth = 16.dp.toPx().roundToInt()
                val availableButtonWidth = if (constraints.hasBoundedWidth) {
                    constraints.maxWidth / measurables.size - hGapWidth * (measurables.size - 1)
                } else {
                    Constraints.Infinity
                }

                val maxIntrinsicWidth = measurables.maxOfOrNull { it.maxIntrinsicWidth(Constraints.Infinity) } ?: error("LOL")
                val buttonWidth = maxIntrinsicWidth.coerceAtMost(availableButtonWidth)
                val buttonConstraints = Constraints(minWidth = buttonWidth, maxWidth = buttonWidth)
                val placeables = measurables.map { it.measure(buttonConstraints) }

                val totalWidth = buttonWidth * measurables.size + hGapWidth * (measurables.size - 1)
                val height = placeables.maxOfOrNull { it.height } ?: error("LOL")
                layout(totalWidth, height) {
                    var currentX = 0
                    for (placeable in placeables) {
                        placeable.placeRelative(currentX, 0)
                        currentX += buttonWidth + hGapWidth
                    }
                }
            }
        }
    }
}

...and here's how it looks:

Changelog

v1.0.1 (14 Jun 2023)

• Fixed bug when buttons would take more space than available — thanks Sam!

v1.0.0 (13 Jun 2023)

• Initial version