今回はJetpack composeでボタンをクリックするごとに色を変えるサンプルプログラムです！

package com.example.btnclick

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
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.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.semantics.Role.Companion.Button
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import com.example.btnclick.ui.theme.BtnClickTheme

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            BtnClickTheme {
                // A surface container using the 'background' color from the theme
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colorScheme.background
                ) {
                    ColorChangingButtons()
                }
            }
        }
    }
}

data class ButtonState(
    var colorIndex: Int = 0
)

@Composable
fun ColorChangingButtons() {
    val colors = listOf(Color.Red, Color.Blue, Color.Green)
    val texts = listOf("あか", "あお", "みどり")
    var buttonStates by remember { mutableStateOf(List(10) { ButtonState() }) }  // 10個のボタン

    Column(modifier = Modifier.padding(16.dp)) {
        buttonStates.forEachIndexed { index, state ->
            CustomButton(
                text = texts[state.colorIndex],
                backgroundColor = colors[state.colorIndex],
                onClick = {
                    buttonStates = buttonStates.toMutableList().apply {
                        this[index] = this[index].copy(colorIndex = (this[index].colorIndex + 1) % colors.size)
                    }
                },
                modifier = Modifier.padding(8.dp)
            )
        }
    }
}

@Composable
fun CustomButton(text: String, backgroundColor: Color, onClick: () -> Unit, modifier: Modifier = Modifier) {
    Column(
        modifier = modifier
            .background(backgroundColor)
            .clickable { onClick() }
            .padding(16.dp)
    ) {
        Text(
            text = text,
            fontSize = 18.sp,
            color = Color.White
        )
    }
}