Problem with qwtPlot / not matching function for call to...

Antonio2178

Hi all,

I wrote a application that plot data with the qwtPlot library.
It will not work fine.
First I try to plot xData and yData in a while loop 5 times with function populate() in plot.cpp.
When I call the function populate() at the end from the constructor Plot::Plot..., the plot are correctly.
But when I call the function populate() from the module modbusadapter.cpp, I became an error message:

no matching function for call to 'Plot::Plot(ModbusAdapter* const)'
candidates are: Plot::Plot(QWidget*)
note: Plot::Plot(const Plot&)

I receive the error only when I allocate memory for plot object in this form:

@plotNewDensity=new Plot(this);@

without the attribute 'this', I can compile, but when I call function populate() in modbusadapter.cpp (after modbus response),
I can see in debug mode that the code jumps in populate(), but without plots...

Here any code segments:

plot.h
@#ifndef PLOT_H
#define PLOT_H

#include <qapplication.h>
#include <qlayout.h>
#include <qwt_plot.h>
#include <qwt_plot_grid.h>
#include <qwt_plot_marker.h>
#include <qwt_plot_curve.h>
#include <qwt_legend.h>
#include <qwt_series_data.h>
#include <qwt_plot_canvas.h>
#include <qwt_plot_panner.h>
#include <qwt_plot_magnifier.h>
#include <qwt_text.h>
#include <qwt_math.h>
#include <math.h>

#define SIZE 15

class Plot : public QwtPlot
{
Q_OBJECT

public:
Plot( QWidget *parent = NULL);
~Plot();
void setPlotValue(double value);
void populate();

protected:
virtual void resizeEvent( QResizeEvent * );

private:
//void populate();
void updateGradient();
double cntX;
QwtPlotCurve *density;
double xData[SIZE];
double yData[SIZE];

public slots:
void addNewValue(double value);
//void populate();

signals:

};
#endif // PLOT_H@

plot.cpp
@#include "plot.h"

Plot::Plot(QWidget *parent):
QwtPlot( parent )
{
xData[0] = 0;
yData[0] = 0;

// Insert new density curve
density = new QwtPlotCurve("y = density");
//density->setRenderHint(QwtPlotItem::RenderAntialiased);
density->setStyle(QwtPlotCurve::Lines);
density->setLegendAttribute(QwtPlotCurve::LegendShowLine, true);
density->setPen(QPen(Qt::red));
density->attach(this);

// Draw grid
QwtPlotGrid *grid = new QwtPlotGrid();
grid->setPen(QPen(Qt::gray, 0.0, Qt::DotLine));
grid->enableX(true);
grid->enableXMin(true);
grid->enableY(true);
grid->enableYMin(false);
grid->attach(this);

// Insert markers
//  ...a horizontal line at y = 0...
QwtPlotMarker *mY = new QwtPlotMarker();
mY->setLabel(QString::fromLatin1("y = 0"));
mY->setLabelAlignment(Qt::AlignRight|Qt::AlignTop);
mY->setLineStyle(QwtPlotMarker::HLine);
mY->setYValue(0.0);
mY->attach(this);

//  ...a vertical line at x = 0...
QwtPlotMarker *mX = new QwtPlotMarker();
mX->setLabel(QString::fromLatin1("x = 0"));
mX->setLabelAlignment(Qt::AlignLeft | Qt::AlignBottom);
mX->setLabelOrientation(Qt::Vertical);
mX->setLineStyle(QwtPlotMarker::VLine);
mX->setLinePen(QPen(Qt::black, 0, Qt::DashDotLine));
mX->setXValue(0.0);
mX->attach(this);

// init private member
//cntX= 0.0;
// init function setPlotValue
//setPlotValue(0.0);
//plotGPS=new QwtPlotCurve();

// panning with the left mouse button
(void) new QwtPlotPanner( canvas() );

// zoom in/out with the wheel
(void) new QwtPlotMagnifier( canvas() );

setAutoFillBackground( true );
setPalette( QPalette( QColor( 165, 193, 228 ) ) );
updateGradient();

setTitle("A Simple QwtPlot Demonstration");
insertLegend(new QwtLegend(), QwtPlot::RightLegend);

// axes
setAxisTitle(xBottom, "x --&gt;" );
setAxisScale(xBottom, 0.0, 10.0);

setAxisTitle(yLeft, "y --&gt;");
setAxisScale(yLeft, -1.0, 1.0);

// canvas
canvas()->setLineWidth( 1 );
canvas()->setFrameStyle( QFrame::Box | QFrame::Plain );
canvas()->setBorderRadius( 15 );

QPalette canvasPalette( Qt::white );
canvasPalette.setColor( QPalette::Foreground, QColor( 133, 190, 232 ) );
canvas()->setPalette( canvasPalette );

//populate();    // when I call here, the plots are correctly...

}

Plot::~Plot()
{

}

void Plot::populate()
{
qWarning()<< "Plot : populate()";

double maxD = 0;
double minD = 1;
double maxS = 0;
double minS = 1;

double dens = 2.0;
unsigned int sample = 0;
unsigned int x = 0;
unsigned int y = 0;

while(sample < 5)
{
    xData[x++]= sample;
    yData[y++]= dens;

    setAxisScale(xBottom, (int)xData[dataCount-1]-iHistorySize, (int)xData[dataCount-1]+1);
    setAxisScale(yLeft, (int)min-1, (int)max+1);

    maxS = sample;
    minS = sample++;
    maxD = dens;
    minD = dens++;

    setAxisScale(xBottom, (int)minS-1, (int)maxS+1);
    setAxisScale(yLeft,   (int)minD-1, (int)maxD+1);

    density->setSamples(xData, yData, sample);
    // Call "replot()" to refresh plot displaying
    replot();
}

}
...
...
...@

Antonio2178

and here the rest:

modbusadapter.h
@#ifndef MODBUSADAPTER_H
#define MODBUSADAPTER_H

#include <QObject>
#include "modbus.h"
#include "registersmodel.h"
#include "rawdatamodel.h"
#include <QTimer>
#include "eutils.h"

#include "plot.h"

class ModbusAdapter : public QObject
{
Q_OBJECT

public:
explicit ModbusAdapter(QObject *parent = 0);

 void busMonitorRequestData(uint8_t * data,uint8_t dataLen);
 void busMonitorResponseData(uint8_t * data,uint8_t dataLen);

 void modbusConnectRTU(QString port, int baud, QChar parity, int dataBits, int stopBits);
 void modbusConnectTCP(QString ip, int port);
 void modbusDisConnect();
 void modbusRequestData(int slave, int functionCode, int startAddress, int noOfItems);
 RegistersModel *regModel;
 RawDataModel *rawModel;
 Plot *plotNewDensity;
 bool isConnected();

...
...
...@

modbusadapter.cpp
@#include "modbusadapter.h"
#include <QMessageBox>
#include <QtDebug>
#include <errno.h>

ModbusAdapter *m_instance;
static const int DBG = false; //Debug messages from libmodbus

ModbusAdapter::ModbusAdapter(QObject *parent) :
QObject(parent),
m_modbus(NULL)
{
m_instance=this;
regModel=new RegistersModel(this);
rawModel=new RawDataModel(this);

plotNewDensity=new Plot(this);

m_connected = false;

}
...
...
...
// after modbus response
plotNewDensity->populate();
...
...
...@

can help anywhere plaese?

thanks and sorry for my english ;)

best regards
Anthony

koahnig

You need to look at the base class of ModbusAdapter which is QObject.

Plot::Plot(QWidget *parent) is expecting a QWidget pointer. QWidget has also QObject as a base class, but the compiler cannot match. That is the error message.

You can use QWidget as base class for ModBusAdapter. That should solve the matching problem. However, you need to check for side effects possibly arising.

Antonio2178

hello koahnig, thanks for the advice...

Now I use QWidget as base class for ModBusAdapter in this way:

@class ModbusAdapter : public QWidget
{
Q_OBJECT

public:
explicit ModbusAdapter(QWidget *parent = 0);
...
...
...@

and

@ModbusAdapter::ModbusAdapter(QWidget *parent) :
QWidget(parent),
m_modbus(NULL)
{
m_instance=this;
regModel=new RegistersModel(this);
rawModel=new RawDataModel(this);

plotNewDensity=new Plot(this);

m_connected = false;

}@

I can compile, but when I jump in populate() from modbusadaapter.cpp after modbus response, still I don't have nothing plots...
When I debug I see again that the jump in populate is ok and the steps and values also but without plots...

What could be the problem?

!https://www.dropbox.com/s/r09yyx8vgf9em5t/plotOk.gif (plot ok, when i call populate() in constructor Plot::Plot...)!

!https://www.dropbox.com/s/4mz55fx8qp58if8/plotNok.gif (without plots, when i call populate() in modbusadapter.cpp after modbus response)!

koahnig

@
void Plot::populate()
{
qWarning()<< "Plot : populate()";

double maxD = 0;
double minD = 1;
double maxS = 0;
double minS = 1;

double dens = 2.0;
unsigned int sample = 0;
unsigned int x = 0;
unsigned int y = 0;

while(sample < 5)
{
    xData[x++]= sample;
    yData[y++]= dens;

    setAxisScale(xBottom, (int)xData[dataCount-1]-iHistorySize, (int)xData[dataCount-1]+1);
    setAxisScale(yLeft, (int)min-1, (int)max+1);

    maxS = sample;
    minS = sample++;
    maxD = dens;
    minD = dens++;

    setAxisScale(xBottom, (int)minS-1, (int)maxS+1);
    setAxisScale(yLeft,   (int)minD-1, (int)maxD+1);

    density->setSamples(xData, yData, sample);
    // Call "replot()" to refresh plot displaying
}
setAutoReplot(true);
replot();

}
@

See, if this helps.

Antonio2178

with

@setAutoReplot(true);@

it still doesn't plot nothing...

Antonio2178

the main looks like

@#include <QtGui/QApplication>
#include "mainwindow.h"
#include "plot.h"

int main(int argc, char *argv[])
{
QApplication a(argc, argv);

Plot *plot = new Plot();

// We put a dummy widget around to have
// so that Qt paints a widget background
// when resizing

QWidget window;
QHBoxLayout *layout = new QHBoxLayout( &window );
layout->setContentsMargins( 0, 0, 0, 0 );
layout->addWidget( plot );

window.resize(600,400);
window.show();

MainWindow w;
w.show();

return a.exec(&#41;;

}@

maybe is that anything wrong?

Antonio2178

do I declare also anything in mainwindow?

here the code:

mainwindow.h
@#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QSettings>
#include <QLabel>
#include <QTimer>
#include "modbus.h"
#include "forms/about.h"
#include "forms/settingsmodbusrtu.h"
#include "forms/settingsmodbustcp.h"
#include "forms/settings.h"
#include "forms/busmonitor.h"
#include "modbusadapter.h"

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
Q_OBJECT

public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();

private:
Ui::MainWindow *ui;
//UI - Dialogs
About *m_dlgAbout;
SettingsModbusRTU *m_dlgModbusRTU;
SettingsModbusTCP *m_dlgModbusTCP;
Settings *m_dlgSettings;
BusMonitor *m_busMonitor;

QSettings *m_modbusCommSettings;
void updateStatusBar();
QLabel *m_statusText;
QWidget *m_statusInd;
ModbusAdapter *m_modbus;
void modbusConnect(bool connect);
QTimer *m_pollTimer;

private slots:
void showSettingsModbusRTU();
void showSettingsModbusTCP();
void showSettings();
void showBusMonitor();
void changedModbusMode(int currIndex);
void changedFunctionCode(int currIndex);
void changedBase(int currIndex);
void changedReqCycle(bool value);
void changedConnect(bool value);
void changedSlaveIP();
void addItems();
void clearItems();
void request();
void pollRequestForData();

};

#endif // MAINWINDOW_H
@

now I have nothing in mainwindow regarding plot...

koahnig

Did you use one of the examples?
If so, maybe you should go back and change step by step. Unfortunately, I do not have enough experience with qwt to help you further.

Antonio2178

yes I have a example. The difference is that the plot layout are implemented directly in mainwindow looks like: !https://www.dropbox.com/s/a9qih7t7ubzq04d/EP24control.gif ()!

in my version I have two window one for plot and the other for modbus communication

here the code of example:

plot.h
@#ifndef PLOT_H
#define PLOT_H

#include <QVector>
#include <qwt_plot.h>
#include <qwt_system_clock.h>
#include <qwt_plot_curve.h>

#define BUFFERSIZE 36000 // Data buffer size (voluntarly laaarge! => 36000 at 10data/s = 1h)

class plot : public QwtPlot
{
Q_OBJECT

public:
plot(QWidget * = NULL);
virtual ~plot();
void start();
void rescaleXaxis(int scale);

private:
QwtPlot *d_plot;

QwtPlotCurve *d_curve;
double  xData[BUFFERSIZE];     // x-data table
double  yData[BUFFERSIZE];     // y-data table
int     dataCount;              // data counter
double  timeData[BUFFERSIZE];
int     iHistorySize;           // history size

QwtSystemClock d_clock;

public slots:
void slot_addPoint(double value);
};

#endif // PLOT_H
@

plot.cpp
@#include "plot.h"
#include <qwt_plot_grid.h>
#include <qwt_plot_layout.h>
#include <qwt_plot_canvas.h>
#include <qwt_plot_marker.h>
#include <qwt_plot_curve.h>
#include <qwt_plot_directpainter.h>
#include <qwt_curve_fitter.h>
#include <qwt_painter.h>
#include <QtDebug>

plot::plot(QWidget *parent):
QwtPlot(parent)
{
// Initialize variables
dataCount = 0;
iHistorySize = 60;
xData[dataCount] = 0;

// Set x-axis scale
rescaleXaxis(iHistorySize);

// Set x-axis label
setAxisTitle(xBottom, "Time [s]");

// Draw grid
QwtPlotGrid *grid = new QwtPlotGrid();
grid->setPen(QPen(Qt::gray, 0.0, Qt::DotLine));
grid->enableX(true);
grid->enableXMin(true);
grid->enableY(true);
grid->enableYMin(false);
grid->attach(this);

// Draw curve
d_curve = new QwtPlotCurve();
d_curve->setStyle(QwtPlotCurve::Lines);
d_curve->setPen(QPen(Qt::blue));
d_curve->attach(this);

}

plot::~plot()
{

}

void plot::start()
{
if(d_clock.isNull())
{
// Start clock
d_clock.start();
}
else
{
dataCount = 0;
xData[dataCount] = 0;

    // Reset x-axis
    rescaleXaxis(iHistorySize);

    // Restart clock
    d_clock.restart();
}

}

// SLOTS
void plot::slot_addPoint(double value)
{
double max = 0;
double min = 1;

// Get elapsed time in seconds
xData[dataCount] = (double)(d_clock.elapsed() / 1000);

// Add y-data
yData[dataCount] = value;

if(xData[dataCount] < BUFFERSIZE)
{
    // Increment data counter
    dataCount++;
}
else
{
    // Shift once
    for(int i=1;i<=dataCount;i++)
    {
        xData[i-1] = xData[i];
        yData[i-1] = yData[i];
    }
}

// Rescale x-axis
rescaleXaxis(iHistorySize);

// Rescale y-axis
for(int i=0; i<dataCount; i++)
{
     if(yData[i] > max)max = yData[i];
     if((yData[i] < 0) && (yData[i] < min))min = yData[i];
}
setAxisScale(yLeft, (int)min-1, (int)max+1);

// Set samples on the curve
d_curve->setSamples(xData, yData, dataCount);

// Call "replot()" to refresh plot displaying
replot();

}

void plot::rescaleXaxis(int scale)
{
// set scale value to iHistorySize
iHistorySize = scale;

// if timer not existing of if current time is less than history size
if(d_clock.isNull() || (xData[dataCount-1] < iHistorySize))
{
    // Set x-axis scale
    setAxisScale(xBottom, 0., iHistorySize);
}
else
{
    // Set x-axis scale
    setAxisScale(xBottom, (int)xData[dataCount-1]-iHistorySize, (int)xData[dataCount-1]+1);
}

// Call "replot()" to refresh plot displaying
replot();

}
@

main
@#include <QtGui/QApplication>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;

// Window icon
QPixmap p(":/icones/progicon");
w.setWindowIcon(p);
w.setWindowTitle("EP24control v1.0.0");

// Window background color
QPalette pal = w.palette();
pal.setColor(w.backgroundRole(), QColor(210,220,230));
w.setPalette(pal);

w.resize(800,600);
w.show();

return a.exec(&#41;;

}
@

Antonio2178

and here the

mainwindow.h
@#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QComboBox>
#include <QPushButton>
#include <QLabel>
#include <QSpinBox>
#include <QLayout>
#include <QGroupBox>
#include <QFile>
#include <QTextStream>
#include <QLineEdit>
#include <QDateTime>
#include "comthread.h"
#include "plot.h"
#include "led.h"

class MainWindow : public QWidget
{
Q_OBJECT

public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();

private:
void refreshComPortList(QComboBox *myComboBox);
ComThread *comThread;
...
...
...
plot *ui_voltagePlot;
plot *ui_currentPlot;
plot *ui_temperaturePlot;
...
...
...
@

and mainwindow.cpp
@#include <QDateTime>
#include <QFileDialog>
#include "mainwindow.h"
#include <QDebug>

MainWindow::MainWindow(QWidget *parent) :
QWidget(parent)
{
...
...
...
// Voltage plot
ui_voltagePlot = new plot(this);
ui_voltagePlot->setAxisScale(QwtPlot::yLeft, 0., 16.);
ui_voltagePlot->setAxisTitle(QwtPlot::yLeft, "Voltage [V]");
// Current plot
ui_currentPlot = new plot(this);
ui_currentPlot->setAxisScale(QwtPlot::yLeft, 0., 10.);
ui_currentPlot->setAxisTitle(QwtPlot::yLeft, "Current [A]");
// Temperature plot
ui_temperaturePlot = new plot(this);
ui_temperaturePlot->setAxisScale(QwtPlot::yLeft, -20., 50.);
ui_temperaturePlot->setAxisTitle(QwtPlot::yLeft, "Temp. [°C]");
...
...
...
// === END OF USER INTERFACE ELEMENTS ===

// === LAYOUT ===

...
...
...

QVBoxLayout *plotLayout = new QVBoxLayout();
plotLayout->addWidget(ui_voltagePlot);
plotLayout->addWidget(ui_currentPlot);
plotLayout->addWidget(ui_temperaturePlot);

QGridLayout *layout = new QGridLayout();
layout->addLayout(plotLayout, 0, 0, 6, 1);

...
...
...

    connect(comThread, SIGNAL(vComSignalVbat(double)), ui_voltagePlot, SLOT(slot_addPoint(double)));
    connect(comThread, SIGNAL(vComSignalCbat(double)), ui_currentPlot, SLOT(slot_addPoint(double)));
    connect(comThread, SIGNAL(vComSignalTonb(double)), ui_temperaturePlot, SLOT(slot_addPoint(double)));

...
....
....

    // Start plot curves creation
    ui_voltagePlot->start();
    ui_currentPlot->start();
    ui_temperaturePlot->start();

...
....
...
// Set new scale
ui_voltagePlot->rescaleXaxis(iHorizontalScale);
ui_currentPlot->rescaleXaxis(iHorizontalScale);
ui_temperaturePlot->rescaleXaxis(iHorizontalScale);

...
...
...
// Set new scale
ui_voltagePlot->rescaleXaxis(iHorizontalScale);
ui_currentPlot->rescaleXaxis(iHorizontalScale);
ui_temperaturePlot->rescaleXaxis(iHorizontalScale);

...
...
@

Antonio2178

maybe is that the problem, bacause I use two different window with two separate "instance" in my version main...

!https://www.dropbox.com/s/5bp1p4sqfa3qm77/window_qwtPlot&modbus.gif ()!