fun main(args: Array<String>) {
    println("Hello, World!")
}import android.Manifest
import android.content.pm.PackageManager
import android.media.MediaRecorder
import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import java.io.IOException
import java.util.*

class MainActivity : AppCompatActivity() {

    private val REQUEST_RECORD_AUDIO_PERMISSION = 200
    private lateinit var mediaRecorder: MediaRecorder
    private var isRecording = false

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        if (ContextCompat.checkSelfPermission(this, Manifest.permission.RECORD_AUDIO) !=
            PackageManager.PERMISSION_GRANTED
        ) {
            ActivityCompat.requestPermissions(
                this,
                arrayOf(Manifest.permission.RECORD_AUDIO),
                REQUEST_RECORD_AUDIO_PERMISSION
            )
        } else {
            startRecording()
        }
    }

    override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        if (requestCode == REQUEST_RECORD_AUDIO_PERMISSION) {
            if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                startRecording()
            } else {
                // Handle permission denied
            }
        }
    }

    private fun startRecording() {
        mediaRecorder = MediaRecorder().apply {
            setAudioSource(MediaRecorder.AudioSource.MIC)
            setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP)
            setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB)
            setOutputFile("${externalCacheDir?.absolutePath}/audio_${Date().time}.3gp")

            try {
                prepare()
                start()
                isRecording = true
                // Here you can schedule a task to stop recording after 400 minutes if needed
            } catch (e: IOException) {
                // Handle exception
            }
        }
    }

    private fun stopRecording() {
        mediaRecorder.apply {
            stop()
            release()
        }
        isRecording = false
    }

    override fun onDestroy() {
        super.onDestroy()
        if (isRecording) {
            stopRecording()
        }
    }
}

Kotlin online compiler

Write, Run & Share Kotlin code online using OneCompiler’s Kotlin online compiler for free. It’s a modern and fast online playground for Kotlin, supporting the latest version and ideal for learning, experimenting, and sharing code instantly.

About Kotlin

Kotlin is a statically typed, modern programming language developed by JetBrains. It runs on the JVM and is fully interoperable with Java. Kotlin is concise, expressive, and safe, and it’s officially supported by Google for Android app development.

Sample Code

The following is a simple Kotlin program that prints a greeting:

fun main() {
    println("Hello, OneCompiler!")
}

Taking inputs (stdin)

OneCompiler’s Kotlin editor supports stdin. You can provide input using the I/O tab. Here's a sample program that reads a line of input and prints a greeting:

fun main() {
    print("Enter your name: ")
    val name = readLine()
    println("Hello, $name")
}

Syntax Basics

Variables

val name: String = "OneCompiler"  // Immutable
var age: Int = 25                 // Mutable

Kotlin supports type inference, so explicit types are optional:

val city = "Hyderabad"
var count = 10

Conditionals

val score = 85
if (score >= 50) {
    println("Pass")
} else {
    println("Fail")
}

Loops

For loop

for (i in 1..5) {
    println(i)
}

While loop

var i = 1
while (i <= 5) {
    println(i)
    i++
}

Do-While loop

var j = 1
do {
    println(j)
    j++
} while (j <= 5)

Functions

fun add(a: Int, b: Int): Int {
    return a + b
}

fun greet(name: String) = "Hello, $name"

Collections

val items = listOf("apple", "banana", "cherry")
for (item in items) {
    println(item)
}

This guide provides a quick reference to Kotlin programming syntax and features. Start coding in Kotlin using OneCompiler’s Kotlin online compiler today!