[SOLVED] Simple QMainWindow subclassing not showing anything

[Jarzka]

MainWindow.cpp
@#include "MainWindow.h"

MainWindow::MainWindow()
{
setWindowTitle("Info");

qHBoxLayoutMain = new QHBoxLayout(this); // makes this layout a child of MainWindow

qFormLayoutForm = new QFormLayout();
qLineEditFirstName = new QLineEdit();
qFormLayoutForm->addRow("First name:", qLineEditFirstName);
qLineEditLastName = new QLineEdit();
qFormLayoutForm->addRow("Last name:", qLineEditLastName);
qPushButtonOk = new QPushButton("OK");
qFormLayoutForm->addRow(qPushButtonOk);

qHBoxLayoutMain->addLayout(qFormLayoutForm);

}
@

main.cpp
@#include "MainWindow.h"

int main(int argc, char *argv[])
{
QApplication app(argc, argv);
MainWindow mainWindow;
mainWindow.show();
return app.exec();
}
@

I thought mainWindow.show() would do this:

• qHBoxLayoutMain->show()
  ** qFormLayoutForm->show()
  *** qLineEditFirstName->show()
  *** qLineEditLastName->show()
  *** qPushButtonOk->show()

But everything I see is an empty window. What's wrong with this?

[Zlatomir]

Is MainWindow class derived from QMainWindow? (if not tell us the base class too, if it's derived from QMainWindow you need to use "centralWidget":http://doc.qt.digia.com/qt/qmainwindow.html#centralWidget to construct your ui into)
Also look at the output console in Creator to see if you got some layout errors.

[Jarzka]

Yes, MainWindow is derived from QMainWindow. And yes I just noticed that I need the central widget and it's missing. My bad.

I added this to my code:
@ centralWidget = new QWidget();
setCentralWidget(centralWidget);

qHBoxLayoutMain = new QHBoxLayout();
centralWidget->setLayout(qHBoxLayoutMain);@

and now it works. :)