QLineEdit editingFinished twice when changing focus?

brman

I know this has been covered a few times before, for instance in this thread....
http://qt-project.org/forums/viewthread/39775
but these appear to refer to cases where a message box is used in the slot handler.

I am a bit stuck as I have it even without any code in the slot handler so stuff like blockSignals() can't solve it.

For a test, I have an array of QLineEdit which use a signalMapper to connect the editingFinished() signals to a single slot. The signalMapper passes the array index so I can see where the signal came from.
eg:
@testenter::testenter(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::testenter)
{
// setup the UI according to the .h file
ui->setupUi(this);

signalMapper = new QSignalMapper(this);

// init the labels and edit boxes
for (int i = 0; i < 10; i++)
{
    pm_label[i] = new QLabel(ui->scrollArea);
    QString text = QString("Number %1").arg(i);
    pm_label[i]->setText(text);
    pm_label[i]->setGeometry(10,20+i*30, 50, 20);
    pm_label[i]->show();

    pm_editBox[i] = new QLineEdit(ui->scrollArea);
    pm_editBox[i]->setGeometry(80,20+i*30, 50, 20);
    pm_editBox[i]->show();

    signalMapper->setMapping(pm_editBox[i], int(i));
    connect(pm_editBox[i], SIGNAL(editingFinished()), signalMapper, SLOT(map()));
}
connect(signalMapper, SIGNAL(mapped(int)), this, SLOT(data_entry(int)));

}

void testenter::data_entry(int entry)
{
//dummy
}
@
When run in the debugger, if I enter data into one box then either hit return or select another box with the mouse (ie change focus) , then it calls data_entry twice, the first time with index of the box that is losing focus and the 2nd time with the box which gets the focus.

Am I missing something? I expected editingFinished to be the best signal to use if I need to act after data is entered (by either return, tab or mouse click) but it doesn't appear I can use it this way.

btw. I've been programming off and on for about 30 years but only recently on C++/Qt so be gentle if I am being stupid ;)