Qt5 creating a Qaction that calls an information window

Question

I am developing a solution in Qt5.4.2, in my menu bar, when clicking an option, a new window should open with that information.

I was thinking about doing one QDialog, but depending on it would get complicated to edit some things and put images, for example. So I created ui'which will be called by these actions triggered by the signal triggered.

But I can’t get the window call to open when the signal is triggered.

I imported the library .h of the window I want to call, in case the aboutMain. I created an object of hers (a new window) and now I want to show.

That’s the way it is?

brprint. h -> . h main

#include <QMainWindow>
#include "loading.h"

namespace Ui {
class BrPrint3D;
}

class BrPrint3D : public QMainWindow
{
    Q_OBJECT

public:
    explicit BrPrint3D(QWidget *parent = 0);
    ~BrPrint3D();
    void init();

private slots:    
    void on_actionSobre_BrPrint3D_triggered();

private:
    Ui::BrPrint3D *ui;

};

brprint3d.cpp

#include "brprint3d.h"
#include "ui_Pandora.h"
#include "aboutbrprint.h"
#include <stdio.h>

//Sobre->Sobre o BrPrint3D
void BrPrint3D::on_actionSobre_BrPrint3D_triggered()
{
    //Chamar Janela Sobre o BrPrint
    aboutBrPrint window;
    window.show();


}

aboutBrPrint. h

#include <QWidget>

namespace Ui {
class aboutBrPrint;
}

class aboutBrPrint : public QWidget
{
    Q_OBJECT

public:
    explicit aboutBrPrint(QWidget *parent = 0);
    ~aboutBrPrint();

private:
    Ui::aboutBrPrint *ui;
};

Main

#include "brprint3d.h"
#include <QApplication>
#include "loading.h"
#include <QTranslator>

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    BrPrint3D w;
    w.show();
    w.init();
    return app.exec();
}

Answer 1

I believe it is necessary to use the new, because the first generated window is already linked to QApplication, the new windows must receive the this to be linked to each other, then the right thing would be this:

void BrPrint3D::on_actionSobre_BrPrint3D_triggered()
{
    aboutBrPrint *window = new aboutBrPrint(this);
    window->show();
}

In the case exec may also work (note that this will probably block the "parent" window while open), as the exec can reference the "parent" window, to unlock the parent window just close the aboutBrPrint:

void BrPrint3D::on_actionSobre_BrPrint3D_triggered()
{
    aboutBrPrint window;
    window.exec();
}

In main.cpp we do not use the constructor new because the first window is already linked to QOBJECT (believe me) that gets connected to the application, then the new is not in "disuse", enjoy and read this link When to choose whether to use a pointer when creating an object?

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    BrPrint3D w;
    w.show();
    w.init();
    return app.exec();
}