iterate through mdiarea subwindows

Question

I have a mdiArea. I add subwindows to this mdiArea every time an image is opened. The widget I set for each subwindow is imageFileDialog which inherits from the QDialog. Within this dialog I have a spinbox. I want to be able to set the value of this spinbox for every dialog I have in the mdiArea after they have been created. I do not know how to iterate through the dialogs. I tried to think of ways to do this.

for (int j=0; j < ui->mdiArea->subWindowList().size(); j++)
{
    imageFileDialog *ifd = ui->mdiArea->subWindowList()[j]->widget();
    ifd->setSpinBox(0);
}

but I have an error because I cannot cast the widget as my imageFileDialog class that inherits from QDialog.

I though I might be able to set a connection upon creation of my imageFileDialog:

imageFileDialog *ifd = new imageFileDialog();
ifd->connect(this, SIGNAL(emitImageFileValue(double)), SLOT(ifd->setSpinBox(double)));
subWindow1->setWidget(ifd);

but this is unlike any connection I've tried to make before. Everything compiles fine, but the signal emitted does not reach my slot. I'm hoping someone has tried this before and has some suggestions! Thanks in advance.

Answer 1

Use qobject_cast for the first problem and for the second issue you need to pass only the slot name to the SLOT() macro (without ifd->), or pass the ifd pointer as separate parameter to connect, something like:

QObject::connect(this, SIGNAL(emitImageFileValue(double)), idf, SLOT(setSpinBox(double)));