嵌入式linux系统中使用QAudioRecorder录音调用Record函数后不产生文件

代码 在构造函数中执行：  

   m_pAudioRecorder =NULL;
    m_pAudioRecorder = new QAudioRecorder();

    if (m_pAudioRecorder->state() == QMediaRecorder::StoppedState)
    {
        //获得可用音频输入的列表
        QStringList inputs = m_pAudioRecorder->audioInputs();
        qDebug()<<"Input Devices Can Used :";
        qDebug() << inputs;
        qDebug()<<"==========="<<endl;
        //获得默认音频输入设备
        qDebug()<<"Default Input Devices :";
        qDebug() << m_pAudioRecorder->defaultAudioInput();
        qDebug()<<"-------------------"<<endl;


        //音频编码器设置
        QAudioEncoderSettings settings = m_pAudioRecorder->audioSettings();
        qDebug()<<"Encoder:"<<endl;
        qDebug() << settings.codec();//windows下默认的是audio/pcm


        settings.setCodec("audio/pcm");
        settings.setSampleRate(1000);
        settings.setChannelCount(0);
        settings.setQuality(QMultimedia::HighQuality);
        settings.setEncodingMode(QMultimedia::ConstantQualityEncoding );

        if(m_pAudioRecorder->setOutputLocation(QUrl::fromLocalFile("/workspace/aaa")))
            qDebug()<<"-------->>>Start OutPutLocation OK!";
        else
            qDebug()<<"-------->>>Start OutPutLocation Failed!";
        qDebug()<<"QUrl::fromLocalFile:"<<QUrl::fromLocalFile("/workspace/aaa");

//StartRecord在主函数中调用

void AudioRecorder::StartRecord()
{
    m_pAudioRecorder->record();
    qDebug()<<"-------->>>Start Audio Recorder...";
}

程序运行后并没有在workspace目录下生成 aaa.wav文件，wav后缀是Qt的这个库会默认添加的