Plotter class

**awpitt13** · 8th February 2012, 23:23

Hello all,

I'm running a data logger and I'm trying to implement a plotter that pops up when a button is pressed on my gui. I am aware of Qwt, but I don't need anything fancy and from what I've read it seems installing it is sort of a pain. Instead, I've been using a plotter class I found in a book I just bought, C++ GUI Programming with Qt 4. Right now the code is setup for plotting two horizontal lines, I'm just trying to get the code functional, I'll worry about getting it functional with my data logger later.

I am getting no errors, nothing seems to happen when I click the button

Here is some of the code;

plotter.h

Qt Code:

Switch view

#ifndef PLOTTER_H
#define PLOTTER_H
 
#include <QMap>
#include <QPixmap>
#include <QVector>
#include <QWidget>
 
class QToolButton;
class PlotSettings;
 
class Plotter : public QWidget
{
       Q_OBJECT
 
public:
       Plotter (QWidget *parent = 0);
 
       void setPlotSettings(const PlotSettings &settings);
       void setCurveData(int id, const QVector<QPointF> &data);
       void clearCurve(int id);
       QSize minimumSizeHint() const;
       QSize sizeHint() const;
 
public slots:
       void zoomIn();
       void zoomOut();
 
protected:
    void paintEvent(QPaintEvent *event);
    void resizeEvent(QResizeEvent *event);
    void mousePressEvent(QMouseEvent *event);
    void mouseMoveEvent(QMouseEvent *event);
    void mouseReleaseEvent(QMouseEvent *event);
    void keyPressEvent(QKeyEvent *event);
    void wheelEvent(QWheelEvent *event);
 
private:
    void updateRubberBandRegion();
    void refreshPixmap();
    void drawGrid(QPainter *painter);
    void drawCurves(QPainter *painter);
 
    enum { Margin = 50 };
 
    QToolButton *zoomInButton;
    QToolButton *zoomOutButton;
    QMap<int, QVector<QPointF> > curveMap;
    QVector<PlotSettings> zoomStack;
    int curZoom;
    bool rubberBandIsShown;
    QRect rubberBandRect;
    QPixmap pixmap;
};
 
class PlotSettings
{
public:
    PlotSettings();
 
    void scroll(int dx, int dy);
    void adjust();
    double spanX() const { return maxX - minX; }
    double spanY() const { return maxY - minY; }
 
    double minX;
    double maxX;
    int numXTicks;
    double minY;
    double maxY;
    int numYTicks;
 
private:
    static void adjustAxis(double &min, double &max, int &numTicks);
};
 
#endif

#ifndef PLOTTER_H
#define PLOTTER_H

#include <QMap>
#include <QPixmap>
#include <QVector>
#include <QWidget>

class QToolButton;
class PlotSettings;

class Plotter : public QWidget
{
       Q_OBJECT

public:
       Plotter (QWidget *parent = 0);
       
       void setPlotSettings(const PlotSettings &settings);
       void setCurveData(int id, const QVector<QPointF> &data);
       void clearCurve(int id);
       QSize minimumSizeHint() const;
       QSize sizeHint() const;

public slots:
       void zoomIn();
       void zoomOut();

protected:
    void paintEvent(QPaintEvent *event);
    void resizeEvent(QResizeEvent *event);
    void mousePressEvent(QMouseEvent *event);
    void mouseMoveEvent(QMouseEvent *event);
    void mouseReleaseEvent(QMouseEvent *event);
    void keyPressEvent(QKeyEvent *event);
    void wheelEvent(QWheelEvent *event);

private:
    void updateRubberBandRegion();
    void refreshPixmap();
    void drawGrid(QPainter *painter);
    void drawCurves(QPainter *painter);

    enum { Margin = 50 };

    QToolButton *zoomInButton;
    QToolButton *zoomOutButton;
    QMap<int, QVector<QPointF> > curveMap;
    QVector<PlotSettings> zoomStack;
    int curZoom;
    bool rubberBandIsShown;
    QRect rubberBandRect;
    QPixmap pixmap;
};

class PlotSettings
{
public:
    PlotSettings();

    void scroll(int dx, int dy);
    void adjust();
    double spanX() const { return maxX - minX; }
    double spanY() const { return maxY - minY; }

    double minX;
    double maxX;
    int numXTicks;
    double minY;
    double maxY;
    int numYTicks;

private:
    static void adjustAxis(double &min, double &max, int &numTicks);
};

#endif

To copy to clipboard, switch view to plain text mode

#include "plotter.h"

plotSettings.cpp

Qt Code:

Switch view

PlotSettings::PlotSettings()
{
minX = 0.0;
maxX = 10.0;
numTicks = 5;
 
minY = 0.0;
maxY = 10.0;
numYTicks = 5;
}
 
//more code...

PlotSettings::PlotSettings()
{
minX = 0.0;
maxX = 10.0;
numTicks = 5;

minY = 0.0;
maxY = 10.0;
numYTicks = 5;
}

//more code...

To copy to clipboard, switch view to plain text mode

here is the implementation file, Plotter.cpp

Qt Code:

Switch view

#include "plotter.h"
#include <QtGui>
 
Plotter::Plotter(QWidget *parent)
    : QWidget(parent)
{
    setBackgroundRole(QPalette::Dark);
    setAutoFillBackground(true);
    setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
    setFocusPolicy(Qt::StrongFocus);
    rubberBandIsShown = false;
 
    zoomInButton = new QToolButton(this);
    zoomInButton->setIcon(QIcon(":/images/zoomin.png"));
    zoomInButton->adjustSize();
    connect(zoomInButton, SIGNAL(clicked()), this, SLOT(zoomIn()));
 
    zoomOutButton = new QToolButton(this);
    zoomOutButton->setIcon(QIcon(":/images/zoomout.png"));
    zoomOutButton->adjustSize();
    connect(zoomOutButton, SIGNAL(clicked()), this, SLOT(zoomOut()));
 
    setPlotSettings(PlotSettings());
}
 
//all the functions follow...

#include "plotter.h"
#include <QtGui>

Plotter::Plotter(QWidget *parent)
    : QWidget(parent)
{
    setBackgroundRole(QPalette::Dark);
    setAutoFillBackground(true);
    setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
    setFocusPolicy(Qt::StrongFocus);
    rubberBandIsShown = false;

    zoomInButton = new QToolButton(this);
    zoomInButton->setIcon(QIcon(":/images/zoomin.png"));
    zoomInButton->adjustSize();
    connect(zoomInButton, SIGNAL(clicked()), this, SLOT(zoomIn()));

    zoomOutButton = new QToolButton(this);
    zoomOutButton->setIcon(QIcon(":/images/zoomout.png"));
    zoomOutButton->adjustSize();
    connect(zoomOutButton, SIGNAL(clicked()), this, SLOT(zoomOut()));

    setPlotSettings(PlotSettings());
}

//all the functions follow...

To copy to clipboard, switch view to plain text mode

Now in my main window I call it

Qt Code:

Switch view

//rest of program code
 
void mainWindow::on_pushButton_clicked()
{
        PlotSettings settings;
        settings.minX(0.0);
        settings.maxX(100.0);
        settings.minY(0.0);
        settings.maxY(100.0);
 
        int numPoints = 100;
        ArrayList<QPointF> points0 = new ArrayList<QPointF>();
        ArrayList<QPointF> points1 = new ArrayList<QPointF>();
        for (int x = 0; x < numPoints; ++x) {
            points0.add(new QPointF(x, Math.random() * 100));
            points1.add(new QPointF(x, Math.random() * 100));
        }
 
        Plotter plotter;
        plotter.setWindowTitle(plotter.tr("Jambi Plotter"));
        plotter.setPlotSettings(settings);
        plotter.setCurveData(0, points0);
        plotter.setCurveData(1, points1);
        plotter.show();
 
//rest of program code
}

//rest of program code

void mainWindow::on_pushButton_clicked()
{
        PlotSettings settings;
        settings.minX(0.0);
        settings.maxX(100.0);
        settings.minY(0.0);
        settings.maxY(100.0);

        int numPoints = 100;
        ArrayList<QPointF> points0 = new ArrayList<QPointF>();
        ArrayList<QPointF> points1 = new ArrayList<QPointF>();
        for (int x = 0; x < numPoints; ++x) {
            points0.add(new QPointF(x, Math.random() * 100));
            points1.add(new QPointF(x, Math.random() * 100));
        }

        Plotter plotter;
        plotter.setWindowTitle(plotter.tr("Jambi Plotter"));
        plotter.setPlotSettings(settings);
        plotter.setCurveData(0, points0);
        plotter.setCurveData(1, points1);
        plotter.show();

//rest of program code
}

To copy to clipboard, switch view to plain text mode

Thank you in advance for any help you can offer

**norobro** · 9th February 2012, 01:46

See comments in the code:

Qt Code:

Switch view

void mainWindow::on_pushButton_clicked()
{
        PlotSettings settings;
        settings.minX(0.0);  // not allowed; use assignment statement
        settings.maxX(100.0); 
        settings.minY(0.0);
        settings.maxY(100.0);
 
        int numPoints = 100;
        QVector<QPointF> points0; // use QVector - no need to create this on the heap
        ArrayList<QPointF> points1  = new ArrayList<QPointF>(); //same as above
        for (int x = 0; x < numPoints; ++x) {
            points0.append(QPointF(x, qrand() % 100)); // use QVector::append(), again no need to create the points on the heap 
							//  see qsrand & qrand()  
            points1.add(new QPointF(x, Math.random() * 100)); //same as above
        }
 
        Plotter plotter;  // This does need to be created on the heap
        plotter.setWindowTitle(plotter.tr("Jambi Plotter"));
        plotter.setPlotSettings(settings);
        plotter.setCurveData(0, points0);
        plotter.setCurveData(1, points1);
        plotter.show();
}

void mainWindow::on_pushButton_clicked()
{
        PlotSettings settings;
        settings.minX(0.0);  // not allowed; use assignment statement
        settings.maxX(100.0); 
        settings.minY(0.0);
        settings.maxY(100.0);

        int numPoints = 100;
        QVector<QPointF> points0; // use QVector - no need to create this on the heap
        ArrayList<QPointF> points1  = new ArrayList<QPointF>(); //same as above
        for (int x = 0; x < numPoints; ++x) {
            points0.append(QPointF(x, qrand() % 100)); // use QVector::append(), again no need to create the points on the heap 
							//  see qsrand & qrand()  
            points1.add(new QPointF(x, Math.random() * 100)); //same as above
        }

        Plotter plotter;  // This does need to be created on the heap
        plotter.setWindowTitle(plotter.tr("Jambi Plotter"));
        plotter.setPlotSettings(settings);
        plotter.setCurveData(0, points0);
        plotter.setCurveData(1, points1);
        plotter.show();
}

To copy to clipboard, switch view to plain text mode

HTH

**awpitt13** · 9th February 2012, 17:46

From your suggestions I have edited my code which can be seen below. When I click this button, nothing seems to happen. I feel like I need a .exec() command somewhere to pop up a new Ui but I'm not sure how to implement this...

Qt Code:

Switch view

void mainWindow::on_pushButton_clicked()
{
        PlotSettings settings;
        settings.minX = 0.0;  
        settings.maxX = 100.0; 
        settings.minY = 0.0;
        settings.maxY = 100.0;
 
        int numPoints = 100;
        QVector<QPointF> points0; 
        QVector<QPointF> points1;
        for (int x = 0; x < numPoints; ++x) {
            points0.append(QPointF(x, qrand() % 100)); 
 
            points1.append(QPointF(x, qrand() % 100)); 
        }
 
        Plotter plotter;  
        plotter.setWindowTitle(plotter.tr("Plotter"));
        plotter.setPlotSettings(settings);
        plotter.setCurveData(0, points0);
        plotter.setCurveData(1, points1);
        plotter.show();
}

void mainWindow::on_pushButton_clicked()
{
        PlotSettings settings;
        settings.minX = 0.0;  
        settings.maxX = 100.0; 
        settings.minY = 0.0;
        settings.maxY = 100.0;

        int numPoints = 100;
        QVector<QPointF> points0; 
        QVector<QPointF> points1;
        for (int x = 0; x < numPoints; ++x) {
            points0.append(QPointF(x, qrand() % 100)); 
							
            points1.append(QPointF(x, qrand() % 100)); 
        }

        Plotter plotter;  
        plotter.setWindowTitle(plotter.tr("Plotter"));
        plotter.setPlotSettings(settings);
        plotter.setCurveData(0, points0);
        plotter.setCurveData(1, points1);
        plotter.show();
}

To copy to clipboard, switch view to plain text mode

**norobro** · 9th February 2012, 18:20

The one thing that you didn't do is create "plotter" on the heap at line 18:

Qt Code:

Switch view

Plotter *plotter = new Plotter;

Plotter *plotter = new Plotter;

To copy to clipboard, switch view to plain text mode

**awpitt13** · 9th February 2012, 22:05

changing line 18 to

Qt Code:

Switch view

Plotter *plotter = new Plotter;

Plotter *plotter = new Plotter;

To copy to clipboard, switch view to plain text mode

results in the following errors:

request for member 'setWindowTitle' in 'plotter' which is of non-class type 'Plotter*'
request for member 'tr' in 'plotter' which is of non-class type 'Plotter*'
request for member 'setPlotSettings' in 'plotter' which is of non-class type 'Plotter*'
request for member 'setCurveData' in 'plotter' which is of non-class type 'Plotter*'
request for member 'setCurveData' in 'plotter' which is of non-class type 'Plotter*'
request for member 'show' in 'plotter' which is of non-class type 'Plotter*'

**norobro** · 9th February 2012, 23:21

You need to use the pointer member selection operator "->" to call each of those methods.

e.g.:

Qt Code:

Switch view

plotter->setWindowTitle(plotter->tr("Plotter"));

plotter->setWindowTitle(plotter->tr("Plotter"));

To copy to clipboard, switch view to plain text mode

**awpitt13** · 9th February 2012, 23:30

Thank you sir, it's working

Thread: Plotter class

Thread Tools

Search Thread

Display

Plotter class

Re: Plotter class

The following user says thank you to norobro for this useful post:

Re: Plotter class

Re: Plotter class

The following user says thank you to norobro for this useful post:

Re: Plotter class

Re: Plotter class

The following user says thank you to norobro for this useful post:

Re: Plotter class

Similar Threads

Curve plotter widget, what's the best strategy?

incremental 2d plotter with QGraphicsView

question about plotter

Compilation Error: base class undefined in the class created from UI file

Plotter

Bookmarks

Bookmarks

Posting Permissions