Do I need to check one by one to know which radiobutton is checked in a group in Qt - c++

Question

I know that I can use this kind of code to know which radio button is checked in Qt:
int checkButton;
if( ui->radioButton_0->isChecked() ){
checkButton = 0;
}else if(ui->radioButton_1->isChecked()){
checkButton = 1;
}else if
...
Are there any easier way to know which radio button is checked in a group in Qt. I think it is really helpful if there is such kind of easier way when the group of radio button is large. Code may look like that:
int checkbutton = groupName.getCheckButtonIngroup();

Answer 1

Also we can put a few radiobuttons in groupbox in Qt Designer and after this find children of groupbox, add children to buttonGroup and use the checkedId or checkedButton methods.
void MainWindow::on_pushButton_15_clicked()
{
QButtonGroup group;
QList<QRadioButton *> allButtons = ui->groupBox->findChildren<QRadioButton *>();
qDebug() <<allButtons.size();
for(int i = 0; i < allButtons.size(); ++i)
{
group.addButton(allButtons[i],i);
}
qDebug() << group.checkedId();
qDebug() << group.checkedButton();
}

Answer 2

First of all you need to add all radio buttons to a button group. There are two ways to do that:
In Qt Designer select all radio buttons you want to add and select Assign to button group from the context menu.
From the code. Create a new QButtonGroup and add the buttons there with QButtonGroup::addButton.
Then anytime you can get to know what button is checked:
If you need a pointer of a checked button use QButtonGroup::checkedButton.
If you need a number of the button you need to add buttons to the group manually with addButton(QAbstractButton* button, int id). After this use QButtonGroup::checkedId to get an identifier of the checked button.