Why Qt can not find a public slot?

**Alex Snet** · 12th April 2009, 19:07

Hi.
When I compile my application compiler says that it can't find two public slots.

Qt Code:

Switch view

Object::connect: No such slot QWidget::geometryClicked(Geometry*,QPoint) in src/mwnd.cpp:28
Object::connect: No such slot QWidget::mouseEventCoordinate(QMouseEvent*,QPointF) in src/mwnd.cpp:46

Object::connect: No such slot QWidget::geometryClicked(Geometry*,QPoint) in src/mwnd.cpp:28
Object::connect: No such slot QWidget::mouseEventCoordinate(QMouseEvent*,QPointF) in src/mwnd.cpp:46

To copy to clipboard, switch view to plain text mode

All the slots are defined in header and are writed in cpp file.

This is the part of code where I connect SIGNAL in mc and l and SLOT in mwnd.

Qt Code:

Switch view

mc = new MapControl( mapMcSize );
    mapadapter = new TileMapAdapter("robots.local", "/maps/maps/%1/%2/%3.png", 256, 0, 17);
    l = new MapLayer("Custom Layer", mapadapter);
    mc->addLayer(l);

mc = new MapControl( mapMcSize );
    mapadapter = new TileMapAdapter("robots.local", "/maps/maps/%1/%2/%3.png", 256, 0, 17);
    l = new MapLayer("Custom Layer", mapadapter);
    mc->addLayer(l);

To copy to clipboard, switch view to plain text mode

27 - 28

Qt Code:

Switch view

connect(l, SIGNAL( geometryClicked(Geometry*,QPoint) ),
            this, SLOT( geometryClicked(Geometry*,QPoint) ));

connect(l, SIGNAL( geometryClicked(Geometry*,QPoint) ),
            this, SLOT( geometryClicked(Geometry*,QPoint) ));

To copy to clipboard, switch view to plain text mode

45-46

Qt Code:

Switch view

connect(mc,SIGNAL(mouseEventCoordinate(const QMouseEvent*,QPointF)),
            this, SLOT(mouseEventCoordinate(QMouseEvent*,QPointF)));

connect(mc,SIGNAL(mouseEventCoordinate(const QMouseEvent*,QPointF)),
            this, SLOT(mouseEventCoordinate(QMouseEvent*,QPointF)));

To copy to clipboard, switch view to plain text mode

Header:

Qt Code:

Switch view

public slots:
    void geometryClicked(Geometry* geom, QPoint coord_px);
    void mouseEventCoordinate(QMouseEvent* event,QPointF point);

public slots:
    void geometryClicked(Geometry* geom, QPoint coord_px);
    void mouseEventCoordinate(QMouseEvent* event,QPointF point);

To copy to clipboard, switch view to plain text mode

CPP:

Qt Code:

Switch view

void mwnd::geometryClicked(Geometry *geom, QPoint)
{
        if (geom->hasClickedPoints())
        {
                QList<Geometry*> pp = geom->clickedPoints();
                for (int i=0; i<pp.size(); i++)
                {
                        QMessageBox::information(this, geom->name(), pp.at(i)->name());
                }
        }
        else if (geom->GeometryType == "Point")
        {
                QMessageBox::information(this, geom->name(), "just a point");
        }
}
void mwnd::mouseEventCoordinate(QMouseEvent *event,QPointF point)
{
    QMessageBox::information(this, "Test", QString("%1 : %2").arg(point.x()).arg(point.y()));
    event->accept();
}

void mwnd::geometryClicked(Geometry *geom, QPoint)
{
        if (geom->hasClickedPoints())
        {
                QList<Geometry*> pp = geom->clickedPoints();
                for (int i=0; i<pp.size(); i++)
                {
                        QMessageBox::information(this, geom->name(), pp.at(i)->name());
                }
        }
        else if (geom->GeometryType == "Point")
        {
                QMessageBox::information(this, geom->name(), "just a point");
        }
}
void mwnd::mouseEventCoordinate(QMouseEvent *event,QPointF point)
{
    QMessageBox::information(this, "Test", QString("%1 : %2").arg(point.x()).arg(point.y()));
    event->accept();
}

To copy to clipboard, switch view to plain text mode

What's I does wrong? Where is my mistake?
(Sorry for bad english)

PS I used qmapcontrol http://www.medieninf.de/qmapcontrol/

**aamer4yu** · 12th April 2009, 20:37

In what class/function are you making the connections ?
Have u used Q_OBJECT in ur class ?

**talk2amulya** · 12th April 2009, 20:48

for some reason, Qt is trying to find the slot in QWidget instead of ur mwnd class

Qt Code:

Switch view

Object::connect: No such slot QWidget::geometryClicked(Geometry*,QPoint) in src/mwnd.cpp:28
Object::connect: No such slot QWidget::mouseEventCoordinate(QMouseEvent*,QPointF) in src/mwnd.cpp:46

Object::connect: No such slot QWidget::geometryClicked(Geometry*,QPoint) in src/mwnd.cpp:28
Object::connect: No such slot QWidget::mouseEventCoordinate(QMouseEvent*,QPointF) in src/mwnd.cpp:46

To copy to clipboard, switch view to plain text mode

..does ur class have any such parenting? could you elaborate a bit on code of mwnd?

**Alex Snet** · 12th April 2009, 20:54

Qt Code:

Switch view

#ifndef MWND_H
#define MWND_H
 
#include <QWidget>
#include <QSettings>
#include "./../maps/qmapcontrol.h"
 
#include "thblackbutton.h"
#include "thblackbar.h"
 
using namespace qmapcontrol;
class mwnd : public QWidget
{
public:
    mwnd();
    ~mwnd();
 
    MapControl* mc;
    MapAdapter* mapadapter;
 
    QPointF coord1;
    QPointF coord2;
 
    Layer* l;
    void createMapControl();
    // Settings
    QSettings sets;
 
public slots:
    void geometryClicked(Geometry* geom, QPoint coord_px);
    void mouseEventCoordinate(QMouseEvent* event,QPointF point);
 
protected:
    void resizeEvent(QResizeEvent *event);
    void wheelEvent(QWheelEvent *event);
};
 
#endif // MWND_H

#ifndef MWND_H
#define MWND_H

#include <QWidget>
#include <QSettings>
#include "./../maps/qmapcontrol.h"

#include "thblackbutton.h"
#include "thblackbar.h"

using namespace qmapcontrol;
class mwnd : public QWidget
{
public:
    mwnd();
    ~mwnd();

    MapControl* mc;
    MapAdapter* mapadapter;

    QPointF coord1;
    QPointF coord2;

    Layer* l;
    void createMapControl();
    // Settings
    QSettings sets;

public slots:
    void geometryClicked(Geometry* geom, QPoint coord_px);
    void mouseEventCoordinate(QMouseEvent* event,QPointF point);

protected:
    void resizeEvent(QResizeEvent *event);
    void wheelEvent(QWheelEvent *event);
};

#endif // MWND_H

To copy to clipboard, switch view to plain text mode

and cpp:

Qt Code:

Switch view

#include "mwnd.h"
 
mwnd::mwnd()
{
    QSize mapMcSize = sets.value("/mwnd/size",QSize(800,600)).value<QSize>();
    this->resize( mapMcSize );
 
 
    QPoint mapMcPos = sets.value("/mwnd/pos",QPoint(100,100)).value<QPoint>();
    this->move( mapMcPos );
 
    mc = new MapControl( mapMcSize );
    mc->showScale(true);
    coord1 = QPointF();
    coord2 = QPointF();
 
    mapadapter = new TileMapAdapter("robots.local", "/maps/maps/%1/%2/%3.png", 256, 0, 17);
 
    // create a layer with the mapadapter and type MapLayer
    l = new MapLayer("Custom Layer", mapadapter);
    mc->addLayer(l);
 
    // Add the Points and the QPen to a LineString
    LineString* ls = new LineString();
    // Add the LineString to the layer
    l->addGeometry(ls);
    connect(l, SIGNAL( geometryClicked(Geometry*,QPoint) ),
            this, SLOT( geometryClicked(Geometry*,QPoint) ));
 
 
   // create buttons as controls for zoom
   QPushButton* zoomin = new QPushButton("+");
   QPushButton* zoomout = new QPushButton("-");
   zoomin->setMaximumWidth(50);
   zoomout->setMaximumWidth(50);
   QSlider* zoomslider = new QSlider(Qt::Vertical,this);
   zoomslider->setMaximum(17);
   zoomslider->setMinimum(0);
   zoomslider->setMaximumHeight( 170 );
 
   connect(zoomin, SIGNAL(clicked(bool)), mc, SLOT(zoomIn()));
   connect(zoomout, SIGNAL(clicked(bool)),mc, SLOT(zoomOut()));
   connect(zoomslider, SIGNAL(valueChanged(int)), mc, SLOT(setZoom(int)));
   connect(mc,SIGNAL(zoomChanged(int)), zoomslider, SLOT(setValue(int)));
   connect(mc,SIGNAL(mouseEventCoordinate(const QMouseEvent*,QPointF)),
            this, SLOT(mouseEventCoordinate(QMouseEvent*,QPointF)));
 
 
   // add zoom buttons to the layout of the MapControl
   QVBoxLayout* plusminusbtn = new QVBoxLayout;
   plusminusbtn->addWidget(zoomin);
   plusminusbtn->addWidget(zoomslider);
   plusminusbtn->addWidget(zoomout);
 
 
   // MapControl layout
   QVBoxLayout* innerlayout = new QVBoxLayout;
   innerlayout->addLayout(plusminusbtn);
   mc->setLayout(innerlayout);
 
    //mc->setView(QPointF(0.00656,0.01929));
    // 55.809952,37.500973
    //GPS_Position pos = GPS_Position(1234567890 ,37.500973,"W",55.809952,"N");
    QPointF coord = sets.value("/mwnd/mc/pos",QPointF( 55.81 , 37.501 )).value<QPointF>();
    mc->setView( coord );
    int zoom = sets.value("/mwnd/mc/zoom", 15).value<int>();
    mc->setZoom(zoom);
 
    ls->addPoint( new CirclePoint( coord.x(), coord.y(),"Start location", Point::Middle) );
 
 
    //QLabel* point;
    //innerlayout->addWidget( point );
    QTabWidget* tabs = new QTabWidget();
    tabs->addTab(mc, "Map");
    //layout->addWidget(mc);
 
    QVBoxLayout* layout = new QVBoxLayout;
    layout->setSpacing(0);
    layout->setContentsMargins(0,0,0,0);
    layout->addWidget( tabs );
    this->setLayout(layout);
 
}
mwnd::~mwnd()
{
    sets.setValue("/mwnd/size",this->size());
    sets.setValue("/mwnd/pos",this->pos());
    sets.setValue("/mwnd/mc/pos", mc->currentCoordinate() );
    sets.setValue("/mwnd/mc/zoom",mc->currentZoom() );
}
 
// Protected methods
void mwnd::resizeEvent(QResizeEvent *event)
{
    //mc->resize( (int) this->size().width(), (int) this->size().height() );
    //qDebug( QString("W: %1  H: %2").arg(this->size().width()).arg(this->size().height()).toAscii() );
    //mc->update();
    event->accept();
    //QWidget::resizeEvent(event);
}
void mwnd::wheelEvent(QWheelEvent *event)
{
    int numDegrees = event->delta() / 8;
    int numSteps = numDegrees / 15;
 
    if (event->orientation() == Qt::Horizontal) {
        // Change view
    } else {
        if(numSteps > 0)
        {
            if(mc->currentZoom()<17)
            {
                mc->zoomIn();
            }
        }
        else
        {
            if(mc->currentZoom()>0)
            {
                mc->zoomOut();
            }
        }
    }
    event->accept();
}
void mwnd::geometryClicked(Geometry *geom, QPoint)
{
        if (geom->hasClickedPoints())
        {
                QList<Geometry*> pp = geom->clickedPoints();
                for (int i=0; i<pp.size(); i++)
                {
                        QMessageBox::information(this, geom->name(), pp.at(i)->name());
                }
        }
        else if (geom->GeometryType == "Point")
        {
                QMessageBox::information(this, geom->name(), "just a point");
        }
}
void mwnd::mouseEventCoordinate(QMouseEvent *event,QPointF point)
{
    QMessageBox::information(this, "Test", QString("%1 : %2").arg(point.x()).arg(point.y()));
    event->accept();
}

#include "mwnd.h"

mwnd::mwnd()
{
    QSize mapMcSize = sets.value("/mwnd/size",QSize(800,600)).value<QSize>();
    this->resize( mapMcSize );


    QPoint mapMcPos = sets.value("/mwnd/pos",QPoint(100,100)).value<QPoint>();
    this->move( mapMcPos );

    mc = new MapControl( mapMcSize );
    mc->showScale(true);
    coord1 = QPointF();
    coord2 = QPointF();

    mapadapter = new TileMapAdapter("robots.local", "/maps/maps/%1/%2/%3.png", 256, 0, 17);

    // create a layer with the mapadapter and type MapLayer
    l = new MapLayer("Custom Layer", mapadapter);
    mc->addLayer(l);

    // Add the Points and the QPen to a LineString
    LineString* ls = new LineString();
    // Add the LineString to the layer
    l->addGeometry(ls);
    connect(l, SIGNAL( geometryClicked(Geometry*,QPoint) ),
            this, SLOT( geometryClicked(Geometry*,QPoint) ));


   // create buttons as controls for zoom
   QPushButton* zoomin = new QPushButton("+");
   QPushButton* zoomout = new QPushButton("-");
   zoomin->setMaximumWidth(50);
   zoomout->setMaximumWidth(50);
   QSlider* zoomslider = new QSlider(Qt::Vertical,this);
   zoomslider->setMaximum(17);
   zoomslider->setMinimum(0);
   zoomslider->setMaximumHeight( 170 );

   connect(zoomin, SIGNAL(clicked(bool)), mc, SLOT(zoomIn()));
   connect(zoomout, SIGNAL(clicked(bool)),mc, SLOT(zoomOut()));
   connect(zoomslider, SIGNAL(valueChanged(int)), mc, SLOT(setZoom(int)));
   connect(mc,SIGNAL(zoomChanged(int)), zoomslider, SLOT(setValue(int)));
   connect(mc,SIGNAL(mouseEventCoordinate(const QMouseEvent*,QPointF)),
            this, SLOT(mouseEventCoordinate(QMouseEvent*,QPointF)));


   // add zoom buttons to the layout of the MapControl
   QVBoxLayout* plusminusbtn = new QVBoxLayout;
   plusminusbtn->addWidget(zoomin);
   plusminusbtn->addWidget(zoomslider);
   plusminusbtn->addWidget(zoomout);


   // MapControl layout
   QVBoxLayout* innerlayout = new QVBoxLayout;
   innerlayout->addLayout(plusminusbtn);
   mc->setLayout(innerlayout);

    //mc->setView(QPointF(0.00656,0.01929));
    // 55.809952,37.500973
    //GPS_Position pos = GPS_Position(1234567890 ,37.500973,"W",55.809952,"N");
    QPointF coord = sets.value("/mwnd/mc/pos",QPointF( 55.81 , 37.501 )).value<QPointF>();
    mc->setView( coord );
    int zoom = sets.value("/mwnd/mc/zoom", 15).value<int>();
    mc->setZoom(zoom);

    ls->addPoint( new CirclePoint( coord.x(), coord.y(),"Start location", Point::Middle) );


    //QLabel* point;
    //innerlayout->addWidget( point );
    QTabWidget* tabs = new QTabWidget();
    tabs->addTab(mc, "Map");
    //layout->addWidget(mc);

    QVBoxLayout* layout = new QVBoxLayout;
    layout->setSpacing(0);
    layout->setContentsMargins(0,0,0,0);
    layout->addWidget( tabs );
    this->setLayout(layout);

}
mwnd::~mwnd()
{
    sets.setValue("/mwnd/size",this->size());
    sets.setValue("/mwnd/pos",this->pos());
    sets.setValue("/mwnd/mc/pos", mc->currentCoordinate() );
    sets.setValue("/mwnd/mc/zoom",mc->currentZoom() );
}

// Protected methods
void mwnd::resizeEvent(QResizeEvent *event)
{
    //mc->resize( (int) this->size().width(), (int) this->size().height() );
    //qDebug( QString("W: %1  H: %2").arg(this->size().width()).arg(this->size().height()).toAscii() );
    //mc->update();
    event->accept();
    //QWidget::resizeEvent(event);
}
void mwnd::wheelEvent(QWheelEvent *event)
{
    int numDegrees = event->delta() / 8;
    int numSteps = numDegrees / 15;

    if (event->orientation() == Qt::Horizontal) {
        // Change view
    } else {
        if(numSteps > 0)
        {
            if(mc->currentZoom()<17)
            {
                mc->zoomIn();
            }
        }
        else
        {
            if(mc->currentZoom()>0)
            {
                mc->zoomOut();
            }
        }
    }
    event->accept();
}
void mwnd::geometryClicked(Geometry *geom, QPoint)
{
        if (geom->hasClickedPoints())
        {
                QList<Geometry*> pp = geom->clickedPoints();
                for (int i=0; i<pp.size(); i++)
                {
                        QMessageBox::information(this, geom->name(), pp.at(i)->name());
                }
        }
        else if (geom->GeometryType == "Point")
        {
                QMessageBox::information(this, geom->name(), "just a point");
        }
}
void mwnd::mouseEventCoordinate(QMouseEvent *event,QPointF point)
{
    QMessageBox::information(this, "Test", QString("%1 : %2").arg(point.x()).arg(point.y()));
    event->accept();
}

To copy to clipboard, switch view to plain text mode

**drhex** · 12th April 2009, 21:34

You need the Q_OBJECT macro in the header of class mwnd.

**Alex Snet** · 12th April 2009, 21:36

Sorry? Can you write a sample?

**Alex Snet** · 12th April 2009, 21:38

Like this?

Qt Code:

Switch view

using namespace qmapcontrol;
class mwnd : public QWidget
{
    Q_OBJECT
public:
    mwnd(QWidget* parent = 0);
    ~mwnd();

using namespace qmapcontrol;
class mwnd : public QWidget
{
    Q_OBJECT
public:
    mwnd(QWidget* parent = 0);
    ~mwnd();

To copy to clipboard, switch view to plain text mode

If I write this - I recieve this:

Qt Code:

Switch view

:-1: error: collect2: ld returned 1 exit status

:-1: error: collect2: ld returned 1 exit status

To copy to clipboard, switch view to plain text mode

**talk2amulya** · 12th April 2009, 22:10

can you post the whole error? this is just linker stopping cuz of some error that occured before

**Alex Snet** · 12th April 2009, 23:55

Sorry, I don't understand.
I write all I have... Where is my bad?

**spirit** · 13th April 2009, 06:47

you have to rebuild your app after adding Q_OBJECT macro.
so, do this

make/mingw32-make/nmake clean
qmake
make/mingw32-make/nmake

**Alex Snet** · 13th April 2009, 08:18

Rebuilding and cleaning does not help =(

Why the compiler can not find the socket if it was declared?

Thread: Why Qt can not find a public slot?

Thread Tools

Search Thread

Display

Hybrid View

Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Re: Why Qt can not find a public slot?

Similar Threads

Problem When Creating my own Slot

problems installing Qt opensource with msvc2008 support

QProcess: several processes connected to same slot - how to find out which emitted?

Link Errors

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions