Call a function at a dialog execution

Nesbit

Hello everybody,

I'm writing an application in which I need to open a dialog and execute automatically (without clicking on a push button for example) some animation function.

For opening the dialog, the main windows has a push button that is connected to a slot, which contains
@
//Open the dialog
dialog dlg=new Dlg ;
dlg.exec();
//Get data from the dialog after it is closed
...@

My dialog class is something like the following, where functionToBeCalled() is the function to be called:
@class Dlg : public QDialog
{
/* ...other attributes and methods here... */

public:
void functionToBeCalled();
}@

Could anybody tell me how to do that please?

Thank you in advance for your help.

lycis

As you are already subclassing QDialog you could probably overwrite the exec() function to call the functionToBeCalled();

A (untested) solution could be:

@
int Dlg::exec()
{
functionToBeCalled();
return QDialog::exec();
}
@

Another approach is to overwrite exec() to emit a signal that is connected to functionToBeCalled(). That would require functionToBeCalled to be defined as slot - or to use another slot to call the function...

Nesbit

Hi Daniel,

Thank you for your reply.

I have tested your 'untested' :D solution. Unfortunately, it is not what I need. Remember that my functionToBeCalled() is a function that does some animation (inside a QGraphicsView), so if we call this function before the exec() function, the user will not see the animation.

I have got an idea but could not make it work. In the following code, I re-implement completely the exec() function, by just copying the source code of QDialog::exec() and adding functionToBeCalled() after show():

@int Dlg::exec()
{
Q_D(QDialog);

if (d->eventLoop) {
    qWarning("QDialog::exec: Recursive call detected");
    return -1;
}

bool deleteOnClose = testAttribute(Qt::WA_DeleteOnClose);
setAttribute(Qt::WA_DeleteOnClose, false);

d->resetModalitySetByOpen();

bool wasShowModal = testAttribute(Qt::WA_ShowModal);
setAttribute(Qt::WA_ShowModal, true);
setResult(0);

//On Windows Mobile we create an empty menu to hide the current menu
#ifdef Q_WS_WINCE_WM
#ifndef QT_NO_MENUBAR
QMenuBar *menuBar = 0;
if (!findChild<QMenuBar *>())
menuBar = new QMenuBar(this);
if (qt_wince_is_smartphone()) {
QAction *doneAction = new QAction(tr("Done"), this);
menuBar->setDefaultAction(doneAction);
connect(doneAction, SIGNAL(triggered()), this, SLOT(_q_doneAction()));
}
#endif //QT_NO_MENUBAR
#endif //Q_WS_WINCE_WM

bool showSystemDialogFullScreen = false;

#ifdef Q_OS_SYMBIAN
if (qobject_cast<QFileDialog *>(this) || qobject_cast<QFontDialog *>(this) ||
qobject_cast<QWizard *>(this)) {
showSystemDialogFullScreen = true;
}
#endif // Q_OS_SYMBIAN

if (showSystemDialogFullScreen) {
    setWindowFlags(windowFlags() | Qt::WindowSoftkeysVisibleHint);
    setWindowState(Qt::WindowFullScreen);
}
show();

/****** MY ANIMATION HERE *******/
functionToBeCalled();

#ifdef Q_WS_MAC
d->mac_nativeDialogModalHelp();
#endif

QEventLoop eventLoop;
d->eventLoop = &eventLoop;
QPointer<QDialog> guard = this;
(void) eventLoop.exec&#40;QEventLoop::DialogExec&#41;;
if (guard.isNull())
    return QDialog::Rejected;
d->eventLoop = 0;

setAttribute(Qt::WA_ShowModal, wasShowModal);

int res = result();
if (deleteOnClose)
    delete this;

#ifdef Q_WS_WINCE_WM
#ifndef QT_NO_MENUBAR
else if (menuBar)
delete menuBar;
#endif //QT_NO_MENUBAR
#endif //Q_WS_WINCE_WM
return res;
}@

The first error I got is 'QDialog::d_func' : cannot access private member declared in class 'QDialog'.
Hope somebody can help.
Have a nice day !