How do you connect the slot of the view with the signal of the class used?

[jeanid]

Hello, everyone, there's a view of MainWindow and a class finder. How do you connect the slot of the MainWindow view with the class finder signal? In the classroom, finder signaled signals: void redraw();

In MainWindow, he announced that he had a class variable.

#include "mainwindow.h"
#include "QtWidgets"
#include <Qpainter>
#include <QDebug>
#include <finder.h>
finder robot;

Next, in MainWindow, trying to connect the class finder signal and the MainWindow slot as follows:

connect(& robot, SIGNAL(redraw()), this, SLOT(update()));

Can you tell me how this problem can be solved?

[derk]

I'll give you a minimum compilable example of how to deal with scattered signals:

mobject.h

#include <QObject>
class QString;
class MObject : public QObject

{

Q_OBJECT

public:

explicit MObject(const QString &objName, QObject *parent = 0);
void emitSignal();
signals:

void testSignal();
public slots:

void testSlot();
};

mobject.cpp:

#include <QDebug>

MObject::MObject(const QString &objName, QObject *parent) :

QObject(parent)

{

setObjectName(objName);

}
void MObject::emitSignal()

{

emit testSignal();

}
void MObject::testSlot()

{

qDebug() << QString("%1::testSlot() call by %2 ")

.arg(this->objectName())

.arg(sender()->objectName());

}

main.cpp:

#include <QCoreApplication>

#include "mobject.h"
int main(int argc, char *argv[])

{

QCoreApplication a(argc, argv);
MObject objA("objA");

MObject objB("objB");
QObject::connect(&objA, &MObject::testSignal, &objB, &MObject::testSlot);

QObject::connect(&objB, &MObject::testSignal, &objA, &MObject::testSlot);
objA.emitSignal();

objB.emitSignal();
return a.exec();

}

Result:

"objB::testSlot() call by objA"

"objA::testSlot() call by objB"