Hi there,

Thanks for this amazing library. I'm net to QT and I was trying to use this tool to plot some real time data.

I followed the basic plotting example and it worked, then I tried to the real-time by following this https://www.qcustomplot.com/index.php/demos/realtimedatademo

Sadly, it did not work, I get an empty graph, the axes are displayed but nothing is drawn on it.

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)

    MainWindow:: makePlot();

    delete ui;

void delay(int n)
    QTime dieTime= QTime::currentTime().addSecs(n);
    while (QTime::currentTime() < dieTime)
        QCoreApplication::processEvents(QEventLoop::AllEvents, 100);

void MainWindow::makePlot(){
    // generate some data:

    QTimer dataTimer;
//QTimer *dataTimer = new QTimer(this);

    ui->customPlot->addGraph(); // blue line
    ui->customPlot->graph(0)->setPen(QPen(QColor(40, 110, 255)));
    ui->customPlot->addGraph(); // red line
    ui->customPlot->graph(1)->setPen(QPen(QColor(255, 110, 40)));

    QSharedPointer<QCPAxisTickerTime> timeTicker(new QCPAxisTickerTime);
    ui->customPlot->yAxis->setRange(-1.2, 1.2);

    // make left and bottom axes transfer their ranges to right and top axes:
    connect(ui->customPlot->xAxis, SIGNAL(rangeChanged(QCPRange)), ui->customPlot->xAxis2, SLOT(setRange(QCPRange)));
    connect(ui->customPlot->yAxis, SIGNAL(rangeChanged(QCPRange)), ui->customPlot->yAxis2, SLOT(setRange(QCPRange)));

    // setup a timer that repeatedly calls MainWindow::realtimeDataSlot:
    std::cout<<"looped in for 1"<<std::endl;
    connect(&dataTimer, SIGNAL(timeout()), this, SLOT(realtimeDataSlot()));
    std::cout<<"looped in for 2"<<std::endl;
    dataTimer.start(0); // Interval 0 means to refresh as fast as possible
    std::cout<<"looped in for 3"<<std::endl;


void MainWindow::realtimeDataSlot()
cout<<"test string"<<endl;
/*the code from the demo page*/}

I added a cout in realtimeDataSlot as you can see and that "test string" never appears, which means the functions is never called...

Could some please help me with this?

Thanks in advance!