Use this to test the memory profiler on android studio using either fetchData or fetchData2

MemoryTestActivity

import android.os.Bundle
import android.os.Debug
import android.util.Log
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.activity.SystemBarStyle
import androidx.compose.foundation.layout.Box
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.Text
import androidx.compose.ui.graphics.toArgb
import androidx.compose.runtime.*
import androidx.compose.runtime.getValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp
import com.tillylabs.androiddemo.ui.theme.AndroidDemoTheme
import kotlinx.coroutines.delay

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge(
            statusBarStyle = SystemBarStyle.light(
                scrim = Color(0xFF1C1C1E).toArgb(),
                darkScrim = Color(0xFF1C1C1E).toArgb()
            ),
            navigationBarStyle = SystemBarStyle.dark(Color(0xFF1C1C1E).toArgb())
        )
        setContent {
            AndroidDemoTheme {
                DemoApp()
            }
        }
    }
}

@Composable
fun DemoApp() {
    var gcCount by remember { mutableLongStateOf(0L) }
    var gcTime by remember { mutableLongStateOf(0L) }
    var lastGcCount by remember { mutableLongStateOf(0L) }
    var gcEventsSinceLastCheck by remember { mutableIntStateOf(0) }

    LaunchedEffect(Unit) {
        while (true) {
            val currentGcCount = Debug.getRuntimeStat("art.gc.gc-count").toLongOrNull() ?: 0
            val currentGcTime = Debug.getRuntimeStat("art.gc.gc-time").toLongOrNull() ?: 0

            if (currentGcCount > lastGcCount) {
                gcEventsSinceLastCheck = (currentGcCount - lastGcCount).toInt()
                Log.d("GC_MONITOR", "GC Event! Total: $currentGcCount, New events: $gcEventsSinceLastCheck")
            }

            gcCount = currentGcCount
            gcTime = currentGcTime
            lastGcCount = currentGcCount

            delay(100) // Check every 100ms
        }
    }

    Box(
        modifier = Modifier
            .fillMaxSize()
    ) {
        Column(
            modifier = Modifier
                .align(Alignment.Center)
                .padding(16.dp)
        ) {
            Text(
                text = """
                    GC Count: $gcCount
                    GC Time: ${gcTime}ms
                """.trimIndent(),
            )
            Button(
                onClick = {
                    fetchData2()
                }
            ) {
                Text("Fetch Data")
            }
        }
    }
}

// Bad!
private fun fetchData() {
    var string = ""
    repeat(50000) {
        string += "a"
    }
    println("String value: $string")
}

// Better!
private fun fetchData2() {
    val stringBuilder = StringBuilder()
    repeat(50000) {
        stringBuilder.append("a")
    }
    println("String value: $stringBuilder")
}