From 73766e462436938806206f1d9efcddee2e17d495 Mon Sep 17 00:00:00 2001
From: Ahmet Inan <xdsopl@gmail.com>
Date: Fri, 12 Apr 2024 18:07:47 +0200
Subject: [PATCH] added audio record

---
 .../java/xdsopl/robot36/MainActivity.java     | 108 ++++++++++++++++++
 app/src/main/res/layout/activity_main.xml     |   1 +
 app/src/main/res/values/strings.xml           |   7 +-
 3 files changed, 115 insertions(+), 1 deletion(-)

diff --git a/app/src/main/java/xdsopl/robot36/MainActivity.java b/app/src/main/java/xdsopl/robot36/MainActivity.java
index c0301c2..782bc54 100644
--- a/app/src/main/java/xdsopl/robot36/MainActivity.java
+++ b/app/src/main/java/xdsopl/robot36/MainActivity.java
@@ -6,16 +6,103 @@ Copyright 2024 Ahmet Inan <xdsopl@gmail.com>
 
 package xdsopl.robot36;
 
+import android.content.pm.PackageManager;
+import android.media.AudioFormat;
+import android.media.AudioRecord;
+import android.media.MediaRecorder;
 import android.os.Bundle;
+import android.Manifest;
+import android.widget.TextView;
 
 import androidx.activity.EdgeToEdge;
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
+import androidx.core.app.ActivityCompat;
+import androidx.core.content.ContextCompat;
 import androidx.core.graphics.Insets;
 import androidx.core.view.ViewCompat;
 import androidx.core.view.WindowInsetsCompat;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class MainActivity extends AppCompatActivity {
 
+	private float[] recordBuffer;
+	private AudioRecord audioRecord;
+
+	private void setStatus(int id) {
+		TextView status = (TextView) findViewById(R.id.status);
+		status.setText(id);
+	}
+
+	private final AudioRecord.OnRecordPositionUpdateListener recordListener = new AudioRecord.OnRecordPositionUpdateListener() {
+		@Override
+		public void onMarkerReached(AudioRecord ignore) {
+		}
+
+		@Override
+		public void onPeriodicNotification(AudioRecord audioRecord) {
+			audioRecord.read(recordBuffer, 0, recordBuffer.length, AudioRecord.READ_BLOCKING);
+		}
+	};
+
+	private void initAudioRecord() {
+		int audioSource = MediaRecorder.AudioSource.UNPROCESSED;
+		int channelConfig = AudioFormat.CHANNEL_IN_MONO;
+		int audioFormat = AudioFormat.ENCODING_PCM_FLOAT;
+		int sampleRate = 8000;
+		int sampleSize = 4;
+		int channelCount = 1;
+		int readsPerSecond = 50;
+		double bufferSeconds = 0.5;
+		int bufferSize = (int) (bufferSeconds * sampleRate * sampleSize);
+		recordBuffer = new float[(sampleRate * channelCount) / readsPerSecond];
+		try {
+			audioRecord = new AudioRecord(audioSource, sampleRate, channelConfig, audioFormat, bufferSize);
+			if (audioRecord.getState() == AudioRecord.STATE_INITIALIZED) {
+				audioRecord.setRecordPositionUpdateListener(recordListener);
+				audioRecord.setPositionNotificationPeriod(recordBuffer.length);
+				startListening();
+			} else {
+				setStatus(R.string.audio_init_failed);
+			}
+		} catch (IllegalArgumentException e) {
+			setStatus(R.string.audio_setup_failed);
+		} catch (SecurityException e) {
+			setStatus(R.string.audio_permission_denied);
+		}
+	}
+
+	private void startListening() {
+		if (audioRecord != null) {
+			audioRecord.startRecording();
+			if (audioRecord.getRecordingState() == AudioRecord.RECORDSTATE_RECORDING) {
+				audioRecord.read(recordBuffer, 0, recordBuffer.length, AudioRecord.READ_BLOCKING);
+				setStatus(R.string.listening);
+			} else {
+				setStatus(R.string.audio_recording_error);
+			}
+		}
+	}
+
+	private void stopListening() {
+		if (audioRecord != null)
+			audioRecord.stop();
+	}
+
+	private final int permissionID = 1;
+
+	@Override
+	public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
+		super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+		if (requestCode != permissionID)
+			return;
+		for (int i = 0; i < permissions.length; ++i)
+			if (permissions[i].equals(Manifest.permission.RECORD_AUDIO) && grantResults[i] == PackageManager.PERMISSION_GRANTED)
+				initAudioRecord();
+	}
+
 	@Override
 	protected void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
@@ -26,5 +113,26 @@ public class MainActivity extends AppCompatActivity {
 			v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom);
 			return insets;
 		});
+		List<String> permissions = new ArrayList<>();
+		if (ContextCompat.checkSelfPermission(this, Manifest.permission.RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED) {
+			permissions.add(Manifest.permission.RECORD_AUDIO);
+			setStatus(R.string.audio_permission_denied);
+		} else {
+			initAudioRecord();
+		}
+		if (!permissions.isEmpty())
+			ActivityCompat.requestPermissions(this, permissions.toArray(new String[0]), permissionID);
+	}
+
+	@Override
+	protected void onResume() {
+		startListening();
+		super.onResume();
+	}
+
+	@Override
+	protected void onPause() {
+		stopListening();
+		super.onPause();
 	}
 }
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index c7a2d54..325241a 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -8,6 +8,7 @@
 	tools:context=".MainActivity">
 
 	<TextView
+		android:id="@+id/status"
 		android:layout_width="wrap_content"
 		android:layout_height="wrap_content"
 		android:text="Hello World!"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 14b357b..72f8c6f 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -1,3 +1,8 @@
 <resources>
 	<string name="app_name">Robot36</string>
-</resources>
\ No newline at end of file
+	<string name="listening">listening</string>
+	<string name="audio_init_failed">audio init failed</string>
+	<string name="audio_setup_failed">audio setup failed</string>
+	<string name="audio_permission_denied">audio permission denied</string>
+	<string name="audio_recording_error">audio recording error</string>
+</resources>