以编程方式连接到配对的蓝牙扬声器并播放音频

3 回答

• 0

  这个对我有用 . 收到BluetoothA2dp.STATE_CONNECTED后，您可以正常播放音乐 .

  public class A2DPActivity extends Activity {
  
  protected static final String TAG = "ZS-A2dp";
  
  Button mBtPlay;
  
  BluetoothAdapter mBtAdapter;
  BluetoothA2dp mA2dpService;
  
  AudioManager mAudioManager;
  MediaPlayer mPlayer;
  
  BroadcastReceiver mReceiver = new BroadcastReceiver() {
  
      @Override
      public void onReceive(Context ctx, Intent intent) {
          String action = intent.getAction();
          Log.d(TAG, "receive intent for action : " + action);
          if (action.equals(BluetoothA2dp.ACTION_CONNECTION_STATE_CHANGED)) {
              int state = intent.getIntExtra(BluetoothA2dp.EXTRA_STATE, BluetoothA2dp.STATE_DISCONNECTED);
              if (state == BluetoothA2dp.STATE_CONNECTED) {
                  setIsA2dpReady(true);
                  playMusic();
              } else if (state == BluetoothA2dp.STATE_DISCONNECTED) {
                  setIsA2dpReady(false);
              }
          } else if (action.equals(BluetoothA2dp.ACTION_PLAYING_STATE_CHANGED)) {
              int state = intent.getIntExtra(BluetoothA2dp.EXTRA_STATE, BluetoothA2dp.STATE_NOT_PLAYING);
              if (state == BluetoothA2dp.STATE_PLAYING) {
                  Log.d(TAG, "A2DP start playing");
                  Toast.makeText(A2DPActivity.this, "A2dp is playing", Toast.LENGTH_SHORT).show();
              } else {
                  Log.d(TAG, "A2DP stop playing");
                  Toast.makeText(A2DPActivity.this, "A2dp is stopped", Toast.LENGTH_SHORT).show();
              }
          }
      }
  
  };
  
  boolean mIsA2dpReady = false;
  void setIsA2dpReady(boolean ready) {
      mIsA2dpReady = ready;
      Toast.makeText(this, "A2DP ready ? " + (ready ? "true" : "false"), Toast.LENGTH_SHORT).show();
  }
  
  private ServiceListener mA2dpListener = new ServiceListener() {
  
      @Override
      public void onServiceConnected(int profile, BluetoothProfile a2dp) {
          Log.d(TAG, "a2dp service connected. profile = " + profile);
          if (profile == BluetoothProfile.A2DP) {
              mA2dpService = (BluetoothA2dp) a2dp;
              if (mAudioManager.isBluetoothA2dpOn()) {
                  setIsA2dpReady(true);
                  playMusic();
              } else {
                  Log.d(TAG, "bluetooth a2dp is not on while service connected");
              }
          }
      }
  
      @Override
      public void onServiceDisconnected(int profile) {
          setIsA2dpReady(false);
      }
  
  };
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      LinearLayout ll = new LinearLayout(this);
      setContentView(ll);
  
      mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
      registerReceiver(mReceiver, new IntentFilter(BluetoothA2dp.ACTION_CONNECTION_STATE_CHANGED));
      registerReceiver(mReceiver, new IntentFilter(BluetoothA2dp.ACTION_PLAYING_STATE_CHANGED));
  
      mBtAdapter = BluetoothAdapter.getDefaultAdapter();
      mBtAdapter.getProfileProxy(this, mA2dpListener , BluetoothProfile.A2DP);
  
  }
  
  @Override
  protected void onDestroy() {
      mBtAdapter.closeProfileProxy(BluetoothProfile.A2DP, mA2dpService);
      releaseMediaPlayer();
      unregisterReceiver(mReceiver);
      super.onDestroy();
  }
  
  @Override
  protected void onPause() {
      releaseMediaPlayer();
      super.onPause();
  }
  
  private void releaseMediaPlayer() {
      if (mPlayer != null) {
          mPlayer.release();
          mPlayer = null;
      }
  }
  
  private void playMusic() {
      mPlayer = new MediaPlayer();
      AssetManager assetManager = this.getAssets();
      AssetFileDescriptor fd;
      try {
          fd = assetManager.openFd("Radioactive.mp3");
          Log.d(TAG, "fd = " + fd);
          mPlayer.setDataSource(fd.getFileDescriptor());
          mPlayer.prepare();
          Log.d(TAG, "start play music");
          mPlayer.start();
      } catch (IOException e) {
          e.printStackTrace();
      }
  }
  

  }

  回复于 2024-04-29T01:50:13+08:00
• 1

  特德

  当我尝试使用BluetoothHeadset时，我遇到了和你一样的问题 . 我想我的工作可能适用于A2DP . 由于我的耳机仅支持免提配置文件 . 我只用BlueHeadset测试 .

  无需 Build RFComm Channels .

  为了我 . 连接到BluetoothHeadsetService后，1 . 检查音频是否已连接

  mBluetoothSpeaker.isAudioConnected(btSpeaker);
  

  2.如果没有， Build 音频连接

  mBluetoothSpeaker.startVoiceRecognition(btSpeaker);
  

  3.为BluetoothHeadset注册BroadcastReceiver.ACTION_CONNECTION_STATE_CHANGED和BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED

  registerReceiver(mReceiver, new IntentFilter(BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED));
  registerReceiver(mReceiver, new IntentFilter(BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED));
  

  4. BroadcastReceiver

  protected BroadcastReceiver mReceiver = new BroadcastReceiver() {
  
      @Override
      public void onReceive(Context context, Intent intent) {
          String action = intent.getAction();
          int state = BluetoothHeadset.STATE_DISCONNECTED;
          int previousState = intent.getIntExtra(BluetoothHeadset.EXTRA_PREVIOUS_STATE, BluetoothHeadset.STATE_DISCONNECTED);
          if (action.equals(BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED)) {
              state = intent.getIntExtra(BluetoothHeadset.EXTRA_STATE, BluetoothHeadset.STATE_DISCONNECTED);
              if (state == BluetoothHeadset.STATE_CONNECTED) {
                  mConnectedHeadset = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                  mInfoTextview.append("\n\nDevice name = " + mConnectedHeadset.getName());
  
                  // Audio should not be connected yet but just to make sure.
                  if (mBluetoothHeadset.isAudioConnected(mConnectedHeadset)) {
                      Log.d(TAG, "Headset audio connected already");
                  } else {
                      if (!mBluetoothHeadset.startVoiceRecognition(mConnectedHeadset)) {
                          Log.e(TAG, "maybe you do not call stopVoiceRecognition previously");
                          mBluetoothHeadset.stopVoiceRecognition(mConnectedHeadset);
                          mBluetoothHeadset.startVoiceRecognition(mConnectedHeadset);
                      }
                  }
              }
              else if (state == BluetoothHeadset.STATE_DISCONNECTED) {
                  mConnectedHeadset = null;
              }
          }
          else if (action.equals(BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED))// audio
          {
              state = intent.getIntExtra(BluetoothHeadset.EXTRA_STATE, BluetoothHeadset.STATE_AUDIO_DISCONNECTED);
              if (state == BluetoothHeadset.STATE_AUDIO_CONNECTED) {
                  // Bluetooth audio connected. you send audio stream to headset now!!!
                  mAudioManager.setMode(AudioManager.STREAM_VOICE_CALL);
                  mMediaPlayer = new MediaPlayer();
                  AssetManager assetManager = getAssets();
                  try {
          AssetFileDescriptor fd = assetManager.openFd("Radioactive.mp3");
          mMediaPlayer.setDataSource(fd.getFileDescriptor());
                      // set audio stream type to STREAM_VOICE_CALL will send audio to headset
                      // @see <a href="http://developer.android.com/reference/android/media/AudioManager.html#startBluetoothSco()">SCO</a>
                      mMediaPlayer.setAudioStreamType(AudioManager.STREAM_VOICE_CALL);
          mMediaPlayer.prepare();
          Log.d(TAG, "start play music");
          mMediaPlayer.start();
          } catch (IOException e) {
          e.printStackTrace();
          }
              }
              else if (state == BluetoothHeadset.STATE_AUDIO_DISCONNECTED) {
                  if (mMediaPlayer != null) {
                  mMediaPlayer.stop();
                  mMediaPlayer = null;
                  }
                  mBluetoothHeadset.stopVoiceRecognition(mConnectedHeadset);
              }
          }   
      }
  };
  

  回复于 2024-04-29T01:50:13+08:00
• 7

  有同样的问题，但发现老帖子：

  Programmatically connect to paired Bluetooth device

  简而言之，为了连接到配对的a2dp设备，你只需要调用BluetoothA2dp.connect（myPairedA2dpDevice），但是现在该方法对公共API是隐藏的，这是没有用的 . 所以你通过Java反射访问它 . 这是一种黑客行为，但谷歌的方式，现在似乎没有一个干净的解决方案 .

  回复于 2024-04-29T01:50:13+08:00