android studio kotlin录音

在Android Studio中使用Kotlin进行录音可以通过使用`MediaRecorder`类来实现。以下是一个简单的示例代码：

import android.Manifest
import android.content.pm.PackageManager
import android.media.MediaRecorder
import android.os.Bundle
import android.os.Environment
import android.widget.Button
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import java.io.IOException

class MainActivity : AppCompatActivity() {

    private val RECORD_AUDIO_PERMISSION = Manifest.permission.RECORD_AUDIO
    private val WRITE_EXTERNAL_STORAGE_PERMISSION = Manifest.permission.WRITE_EXTERNAL_STORAGE

    private val REQUEST_PERMISSION_CODE = 101

    private var mediaRecorder: MediaRecorder? = null
    private var isRecording = false

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

        val recordButton = findViewById<Button>(R.id.record_button)
        recordButton.setOnClickListener {
            if (isRecording) {
                stopRecording()
                recordButton.text = "Start Recording"
            } else {
                if (checkPermissions()) {
                    startRecording()
                    recordButton.text = "Stop Recording"
                }
            }
        }
    }

    private fun checkPermissions(): Boolean {
        val permissionRecordAudio = ContextCompat.checkSelfPermission(
            this, RECORD_AUDIO_PERMISSION
        )
        val permissionWriteExternalStorage = ContextCompat.checkSelfPermission(
            this, WRITE_EXTERNAL_STORAGE_PERMISSION
        )

        val permissionsToRequest = ArrayList<String>()
        if (permissionRecordAudio != PackageManager.PERMISSION_GRANTED) {
            permissionsToRequest.add(RECORD_AUDIO_PERMISSION)
        }
        if (permissionWriteExternalStorage != PackageManager.PERMISSION_GRANTED) {
            permissionsToRequest.add(WRITE_EXTERNAL_STORAGE_PERMISSION)
        }

        if (permissionsToRequest.isNotEmpty()) {
            ActivityCompat.requestPermissions(
                this, permissionsToRequest.toTypedArray(), REQUEST_PERMISSION_CODE
            )
            return false
        }

        return true
    }

    private fun startRecording() {
        val filePath = "${Environment.getExternalStorageDirectory().absolutePath}/recording.3gp"
        mediaRecorder = MediaRecorder().apply {
            setAudioSource(MediaRecorder.AudioSource.MIC)
            setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP)
            setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB)
            setOutputFile(filePath)
            try {
                prepare()
                start()
                isRecording = true
                Toast.makeText(this@MainActivity, "Recording started", Toast.LENGTH_SHORT).show()
            } catch (e: IOException) {
                e.printStackTrace()
            }
        }
    }

    private fun stopRecording() {
        mediaRecorder?.apply {
            stop()
            reset()
            release()
            mediaRecorder = null
            isRecording = false
            Toast.makeText(this@MainActivity, "Recording stopped", Toast.LENGTH_SHORT).show()
        }
    }

    override fun onRequestPermissionsResult(
        requestCode: Int, permissions: Array<out String>, grantResults: IntArray
    ) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        if (requestCode == REQUEST_PERMISSION_CODE) {
            if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                if (isRecording) {
                    startRecording()
                }
            } else {
                Toast.makeText(
                    this,
                    "Permission denied. Please grant the necessary permissions.",
                    Toast.LENGTH_SHORT
                ).show()
            }
        }
    }
}

请确保在使用之前在`AndroidManifest.xml`文件中添加以下权限：

<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

这段代码创建了一个简单的界面，其中有一个按钮用于开始和停止录音。录制的音频文件将保存在设备的外部存储目录中，并以`recording.3gp`命名。请确保在运行应用程序之前为应用程序授予适当的权限。

希望这能帮到你！