widget.cpp 范例文件

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#include "widget.h"
#include <QtMultimedia/QAudioDeviceInfo>
#include <QtMultimedia/QAudioInput>
#include <QtCharts/QChartView>
#include <QtCharts/QLineSeries>
#include <QtCharts/QChart>
#include <QtWidgets/QVBoxLayout>
#include <QtCharts/QValueAxis>
#include "xyseriesiodevice.h"
QT_CHARTS_USE_NAMESPACE
Widget::Widget(QWidget *parent)
    : QWidget(parent),
      m_device(0),
      m_chart(0),
      m_series(0),
      m_audioInput(0)
{
    m_chart = new QChart;
    QChartView *chartView = new QChartView(m_chart);
    chartView->setMinimumSize(800, 600);
    m_series = new QLineSeries;
    m_chart->addSeries(m_series);
    QValueAxis *axisX = new QValueAxis;
    axisX->setRange(0, 2000);
    axisX->setLabelFormat("%g");
    axisX->setTitleText("Samples");
    QValueAxis *axisY = new QValueAxis;
    axisY->setRange(-1, 1);
    axisY->setTitleText("Audio level");
    m_chart->setAxisX(axisX, m_series);
    m_chart->setAxisY(axisY, m_series);
    m_chart->legend()->hide();
    m_chart->setTitle("Data from the microphone");
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(chartView);
    setLayout(mainLayout);
    QAudioFormat formatAudio;
    formatAudio.setSampleRate(8000);
    formatAudio.setChannelCount(1);
    formatAudio.setSampleSize(8);
    formatAudio.setCodec("audio/pcm");
    formatAudio.setByteOrder(QAudioFormat::LittleEndian);
    formatAudio.setSampleType(QAudioFormat::UnSignedInt);
    QAudioDeviceInfo inputDevices = QAudioDeviceInfo::defaultInputDevice();
    m_audioInput = new QAudioInput(inputDevices,formatAudio, this);
    m_device = new XYSeriesIODevice(m_series, this);
    m_device->open(QIODevice::WriteOnly);
    m_audioInput->start(m_device);
}
Widget::~Widget()
{
    m_audioInput->stop();
    m_device->close();
}