#Android 实现蓝牙录音
本文实现使用AudioRecord 来进行蓝牙录音。
主要是通过打开蓝牙SCO通路实现。
app的界面
实现功能：普通录音、停止、播放和蓝牙录音、停止、播放。
具体的实现过程：
这里封装了打开SCO的工具类。
先是打开SCO通道后进行蓝牙录音。
使用AudioRecord 来进行蓝牙录音。
使用AudioTrack 来进行播放。
下面是打开SCO的工具类：
```
package com.recorder.huawei.recorderdemo;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.media.AudioManager;
import android.support.annotation.NonNull;
import android.util.Log;
public class BluetoothUtil {
private String TAG = "BluetoothUtil";
private static BluetoothUtil mBluetoothUtil;
//第一次打开sco没成功的情况，持续连接的次数
private static final int SCO_CONNECT_TIME = 5;
private int mConnectIndex = 0;
private AudioManager mAudioManager = null;
static Context mContext;
private BluetoothUtil() {
if (mAudioManager == null) {
mAudioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
}
}
public static BluetoothUtil getInstance(Context context) {
mContext = context;
if (mBluetoothUtil == null) {
mBluetoothUtil = new BluetoothUtil();
}
return mBluetoothUtil;
}
public void openSco(@NonNull final IBluetoothConnectListener listener) {
if (!mAudioManager.isBluetoothScoAvailableOffCall()) {
Log.e(TAG, "系统不支持蓝牙录音");
listener.onError("Your device no support bluetooth record!");
return;
}
new Thread(new Runnable() {
@Override
public void run() {
//mAudioManager = (AudioManager)getSystemService(Context.AUDIO_SERVICE);
//蓝牙录音的关键，启动SCO连接，耳机话筒才起作用
mAudioManager.stopBluetoothSco();
mAudioManager.startBluetoothSco();
//蓝牙SCO连接建立需要时间，连接建立后会发出ACTION_SCO_AUDIO_STATE_CHANGED消息，通过接收该消息而进入后续逻辑。
//也有可能此时SCO已经建立，则不会收到上述消息，可以startBluetoothSco()前先
//stopBluetoothSco()
mConnectIndex = 0;
mContext.registerReceiver(new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
int state = intent.getIntExtra(AudioManager.EXTRA_SCO_AUDIO_STATE, -1);
boolean bluetoothScoOn = mAudioManager.isBluetoothScoOn();
Log.i(TAG, "onReceive state=" + state + ",bluetoothScoOn=" + bluetoothScoOn);
if (AudioManager.SCO_AUDIO_STATE_CONNECTED == state) { // 判断值是否是：1
Log.e(TAG, "onReceive success!");
mAudioManager.setBluetoothScoOn(true); //打开SCO
listener.onSuccess();
mContext.unregisterReceiver(this); //取消广播，别遗漏
} else {//等待一秒后再尝试启动SCO
Log.e(TAG, "onReceive failed index=" + mConnectIndex);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (mConnectIndex < SCO_CONNECT_TIME) {
mAudioManager.startBluetoothSco();//再次尝试连接
} else {
listener.onError("open sco failed!");
mContext.unregisterReceiver(this); //取消广播，别遗漏
}
mConnectIndex++;
}
}
}, new IntentFilter(AudioManager.ACTION_SCO_AUDIO_STATE_UPDATED));
}
}).start();
}
public void closeSco() {
boolean bluetoothScoOn = mAudioManager.isBluetoothScoOn();
Log.i(TAG, "bluetoothScoOn=" + bluetoothScoOn);
if (bluetoothScoOn) {
mAudioManager.setBluetoothScoOn(false);
mAudioManager.stopBluetoothSco();
}
mBluetoothConnectListener = null;
}
public interface IBluetoothConnectListener {
void onError(String error);
void onSuccess();
}
IBluetoothConnectListener mBluetoothConnectListener;
}
```
