启用麦克风后，一台设备无法通过听筒播放音频通话

Question

我正在编写信使（具有 VoIP 功能），用户可以在其中单独关闭/打开扬声器和麦克风。我刚刚添加了一个功能，用户可以将手机放在耳边，然后屏幕关闭，他可以通过耳机听到对话。这是问题所在。在一台设备上（使用自定义固件），当我同时打开扬声器和麦克风并将手机放在耳边时，我什么也听不见。

我的部分代码：

打开扬声器：

private void headsetStart()
{
    if (mPlayMessages == null)
    {
        mHeadsetButton.setBackgroundResource(R.drawable.headset_on);

        audioManager.setMode(audioManager.MODE_IN_COMMUNICATION);
        audioManager.setSpeakerphoneOn(!nearProximity);

        // turn off screen on near proximity sensor
        mWakeLock = mPowerManager.newWakeLock(PowerManager.PROXIMITY_SCREEN_OFF_WAKE_LOCK, ":headsetStart");
        mWakeLock.acquire();
        mBeOnAirThread = new BeOnAirThread();
        mBeOnAirThread.start();

        if (partnerOnAir && !mIsStarted)
        {
            micStart();
        }
    }
}

private class BeOnAirThread extends Thread {

    // Sample rate must be one supported by Opus.
    static final int SAMPLE_RATE = 16000;

    // Number of samples per frame is not arbitrary,
    // it must match one of the predefined values, specified in the standard.
    static final int FRAME_SIZE = 160;

    // 1 or 2
    static final int NUM_CHANNELS = 1;

    @Override
    public void run() {
        Process.setThreadPriority(Process.THREAD_PRIORITY_MORE_FAVORABLE);

        int minBufSize = AudioRecord.getMinBufferSize(SAMPLE_RATE,
                NUM_CHANNELS == 1 ? AudioFormat.CHANNEL_IN_MONO : AudioFormat.CHANNEL_IN_STEREO,
                AudioFormat.ENCODING_PCM_16BIT);

        // init audio track
        AudioTrack track = new AudioTrack(AudioManager.STREAM_VOICE_CALL,
                SAMPLE_RATE,
                NUM_CHANNELS == 1 ? AudioFormat.CHANNEL_OUT_MONO : AudioFormat.CHANNEL_OUT_STEREO,
                AudioFormat.ENCODING_PCM_16BIT,
                minBufSize,
                AudioTrack.MODE_STREAM);
.....................................

初始化麦克风：

private class RecordThread extends Thread {
    // Sample rate must be one supported by Opus.
    static final int SAMPLE_RATE = 16000;

    // Number of samples per frame is not arbitrary,
    // it must match one of the predefined values, specified in the standard.
    static final int FRAME_SIZE = 160;

    // 1 or 2
    static final int NUM_CHANNELS = 1;

    byte[] textBuf;
    int iav;
    int off;

    @Override
    public void run() {
        Process.setThreadPriority(Process.THREAD_PRIORITY_MORE_FAVORABLE);

        int minBufSize = AudioRecord.getMinBufferSize(SAMPLE_RATE,
                NUM_CHANNELS == 1 ? AudioFormat.CHANNEL_IN_MONO : AudioFormat.CHANNEL_IN_STEREO,
                AudioFormat.ENCODING_PCM_16BIT);

        // initialize audio recorder
        AudioRecord recorder = new AudioRecord(MediaRecorder.AudioSource.VOICE_COMMUNICATION,
                SAMPLE_RATE,
                NUM_CHANNELS == 1 ? AudioFormat.CHANNEL_IN_MONO : AudioFormat.CHANNEL_IN_STEREO,
                AudioFormat.ENCODING_PCM_16BIT,
                minBufSize);
..........................................

经验证明，如果在“audioManager.setSpeakerphoneOn(!nearProximity)”之前停止 RecordThread 并在它之后重新启动它，那么耳机就可以工作。 但是对我来说重新连接到服务器是不可取的。所以我也尝试在“audioManager.setSpeakerphoneOn(!nearProximity)”之前做“recorder.stop();recorder.release()”并在它之后重建新的AudioRecord，但它没有帮助。

有什么想法吗？

Answer 1

终于成功了。

实验表明我真的不需要发布和重建 AudioRecord。

我所需要的只是“audioManager.setSpeakerphoneOn(!nearProximity);”之间的一些延迟（约 1 秒）和“recorder.startRecording();”

@Override
public void onSensorChanged(SensorEvent event) {
    if (event.sensor.getType() == Sensor.TYPE_PROXIMITY) {
        boolean oldNear = nearProximity;
        if (event.values[0] >= -SENSOR_SENSITIVITY && event.values[0] <= SENSOR_SENSITIVITY) {
            nearProximity = true;
        } else {
            nearProximity = false;
        }

        if (mBeOnAirThread != null && oldNear != nearProximity)
        {
            if (nearProximity && mIsStarted)
                nearChanged = true;
            else
                audioManager.setSpeakerphoneOn(!nearProximity);
        }
    }
}

在记录循环中：

                if (nearChanged)
                {
                    recorder.stop();
                    audioManager.setSpeakerphoneOn(!nearProximity);

                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                    }

                    recorder.startRecording();
                    nearChanged = false;
                }