Opening a new window

[k12yp70n]

Hi there, folks!!

I have a bit of a problem here with being able to declare an object from a class derived from a UI file designed with Qt Designer, in other words:

in adddialog.h,

#ifndef ADDDIALOG_H
#define ADDDIALOG_H
#include "ui_adddialog.h"
 
class adddialog : public QDialog, private Ui::AddDLG {
    Q_OBJECT
public:
    adddialog ();
};
#endif // ADDDIALOG_H

#ifndef ADDDIALOG_H
#define ADDDIALOG_H
#include "ui_adddialog.h"

class adddialog : public QDialog, private Ui::AddDLG {
    Q_OBJECT
public:
    adddialog ();
};
#endif // ADDDIALOG_H

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in adddialog.cpp,

#include "adddialog.h"
 
adddialog::adddialog() {
    setupUi(this);
}

#include "adddialog.h"

adddialog::adddialog() {
    setupUi(this);
}

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and in the implementation of the main window,

#include "adddialog.h"
...
void mainwindow::adddialog() {
    adddialog add;
    add.show();
}

#include "adddialog.h"
...
void mainwindow::adddialog() {
    adddialog add;
    add.show();
}

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void adddialog in the class mainwindow is a slot, later used to connect a button to it, and hence make an "Add Dialog" launch whenever the button is clicked.
When I run this code I get the following errors:

"expected ; before 'add' "
"statement cannot resolve address of overloaded function"
" 'add' was not declared in this scope"

What am I doing wrong??? As usual sample code would be very appreaciated.

Thanks in advance