Error to declare signal

Hello All!

I am trying to declare a signal as the code below shows:
bancodados.h

Code:

---

#ifndef BANCODADOS_H
#define BANCODADOS_H
 
#include <QObject>
 
class bancoDados : public QObject
{
    Q_OBJECT
 
public:
    explicit bancoDados(QObject *parent = 0);
 
signals:
    void conectar();
 
public slots:
 
};

---

bancodados.cpp

Code:

---

#include "bancodados.h"
 
#include <QSqlDatabase>
 
bancoDados::bancoDados(QObject *parent) :
    QObject(parent)
{
 
}
void bancoDados::conectar()
{
    bool retorno = true;
 
    emit retorno;
}

---

Well, when I run this code it show the error:

Code:

---

:-1: error: 1 duplicate symbol for architecture x86_64

---

But, if I change "void conectar();" from signals to public, it runs, but I need to it stays as a signal

Can anyone help me?

Thanks a lot.

Signals don't have code.

This code is wrong:

Code:

---

void bancoDados::conectar()
{
    bool retorno = true;
 
    emit retorno;
}

---

To emit a signal you just need to declare it (with arguments if needed):

Code:

---

signals:
    void conectar();

---

And then emit it when needed:

Code:

---

emit conectar();

---

If you need to pass that boolean value to the signal you declare it and pass the boolean as argument:

Code:

---

signals:
    void conectar(bool);

---

Code:

---

emit conectar(true);

---

Thaks a lot