android 怎么连接蓝牙录音示例代码

以下是一个简单的Android蓝牙录音示例代码，它可以连接到蓝牙设备并录制音频：

MainActivity.java

import android.Manifest;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.media.MediaRecorder;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.util.UUID;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "MainActivity";
    private static final int REQUEST_ENABLE_BT = 1;
    private static final int PERMISSION_REQUEST_CODE = 2;
    private static final String FILE_NAME = "recording.3gp";
    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
    private BluetoothAdapter mBluetoothAdapter;
    private BluetoothSocket mBluetoothSocket;
    private OutputStream mOutputStream;
    private MediaRecorder mMediaRecorder;
    private Button mStartRecordingButton;
    private Button mStopRecordingButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mStartRecordingButton = findViewById(R.id.start_recording_button);
        mStopRecordingButton = findViewById(R.id.stop_recording_button);

        mStartRecordingButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (checkPermissions()) {
                    startRecording();
                } else {
                    requestPermissions();
                }
            }
        });

        mStopRecordingButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                stopRecording();
            }
        });

        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        if (mBluetoothAdapter == null) {
            Toast.makeText(this, "Bluetooth is not available", Toast.LENGTH_LONG).show();
            finish();
            return;
        }

        if (!mBluetoothAdapter.isEnabled()) {
            Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (mBluetoothSocket != null) {
            try {
                mBluetoothSocket.close();
            } catch (IOException e) {
                Log.e(TAG, "Error closing Bluetooth socket", e);
            }
        }
    }

    private boolean checkPermissions() {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
            return true;
        }
        return ContextCompat.checkSelfPermission(this, Manifest.permission.RECORD_AUDIO) == PackageManager.PERMISSION_GRANTED
                && ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED;
    }

    private void requestPermissions() {
        ActivityCompat.requestPermissions(this,
                new String[]{Manifest.permission.RECORD_AUDIO, Manifest.permission.WRITE_EXTERNAL_STORAGE},
                PERMISSION_REQUEST_CODE);
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        if (requestCode == PERMISSION_REQUEST_CODE) {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED
                    && grantResults[1] == PackageManager.PERMISSION_GRANTED) {
                startRecording();
            } else {
                Toast.makeText(this, "Permissions not granted", Toast.LENGTH_LONG).show();
            }
        }
    }

    private void startRecording() {
        try {
            BluetoothDevice device = mBluetoothAdapter.getRemoteDevice("00:11:22:33:44:55"); // replace with your Bluetooth device address
            mBluetoothSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
            mBluetoothSocket.connect();
            mOutputStream = mBluetoothSocket.getOutputStream();

            mMediaRecorder = new MediaRecorder();
            mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
            mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
            mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
            mMediaRecorder.setOutputFile(getFilePath());

            mMediaRecorder.prepare();
            mMediaRecorder.start();

            mStartRecordingButton.setEnabled(false);
            mStopRecordingButton.setEnabled(true);
            Toast.makeText(this, "Recording started", Toast.LENGTH_LONG).show();
        } catch (IOException e) {
            Log.e(TAG, "Error connecting to Bluetooth device", e);
            Toast.makeText(this, "Error connecting to Bluetooth device", Toast.LENGTH_LONG).show();
        } catch (IllegalStateException e) {
            Log.e(TAG, "Error starting media recorder", e);
            Toast.makeText(this, "Error starting media recorder", Toast.LENGTH_LONG).show();
        }
    }

    private void stopRecording() {
        try {
            mMediaRecorder.stop();
            mMediaRecorder.release();
            mMediaRecorder = null;

            mOutputStream.close();
            mBluetoothSocket.close();

            mStartRecordingButton.setEnabled(true);
            mStopRecordingButton.setEnabled(false);
            Toast.makeText(this, "Recording stopped", Toast.LENGTH_LONG).show();
        } catch (IOException e) {
            Log.e(TAG, "Error closing Bluetooth socket", e);
            Toast.makeText(this, "Error closing Bluetooth socket", Toast.LENGTH_LONG).show();
        } catch (IllegalStateException e) {
            Log.e(TAG, "Error stopping media recorder", e);
            Toast.makeText(this, "Error stopping media recorder", Toast.LENGTH_LONG).show();
        }
    }

    private String getFilePath() {
        File directory = Environment.getExternalStorageDirectory();
        return directory.getAbsolutePath() + "/" + FILE_NAME;
    }
}

注意替换以下两个部分中的蓝牙设备地址：

BluetoothDevice device = mBluetoothAdapter.getRemoteDevice("00:11:22:33:44:55"); // replace with your Bluetooth device address

和

private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

要连接到蓝牙设备，您需要在BluetoothAdapter上调用getRemoteDevice()方法，并传递设备的物理地址。然后，您需要使用该设备的createRfcommSocketToServiceRecord()方法创建一个BluetoothSocket对象。然后，您可以使用该对象的connect()方法连接到蓝牙设备。

一旦连接成功，您可以通过调用BluetoothSocket对象的getOutputStream()方法获取输出流。您可以将此输出流用作MediaRecorder的输出文件。录制音频后，关闭输出流和蓝牙套接字