passing tuple with pyqt4 signal/slot mechanism

[Diez B. Roggisch]

Pradnyesh Sawant schrieb:
> Hello,
> I have a pyqt4 code in which i'm trying the signal/slot mechanism. The
> (stripped) code is as follows:
> 
> class D(QtCore.QThread):
>    def __init__(self):
>        QtCore.QThread.__init__(self)
>        tpl = ("Primary", "priSec")
>        print "tpl:", tpl
>        self.emit(QtCore.SIGNAL("setLabel"), tpl)
> class Gui(QtGui.QDialog):
>    def __init__(self, parent = None):
>        QtGui.QDialog.__init__(self, parent)
>    def setLabel(self, tpl):
>        print "####tpl:", tpl
>        print "**********tpl:", str(tpl)
>        return
> if __name__ == "__main__":
>    app = QtGui.QApplication(sys.argv)
>    dialog = Gui()
>    d = D()
>    QtCore.QObject.connect(d, QtCore.SIGNAL("setLabel"),
>            dialog.setLabel, QtCore.Qt.QueuedConnection)
>    sys.exit(dialog.exec_())
> 
> The output i'm getting is as follows:
> 
> tpl: ('Primary', 'priSec')
> ####tpl: (<refcnt 0 at 0xb7caac8c>,)
> **********tpl: ((((((((<NULL>,),),),),),),),)
> 
> Can anyone kindly tell me what's happening here? Why is the tuple
> ("Primary", "priSec") getting converted to this <NULL> thingy? And
> what is this thingy anyways (It looks to be a deeply nested tuple, but
> am not sure).

It's just wild guessing back from my Qt3-days - but isn't PYSIGNAL 
instead of SIGNAL necessary here?

Diez