Python new style signals and slot between thread and gui app

Question

I am newbie to OOP and python. I am trying to emit signal from Qthread to Qt GUI main window using new style signals and slots.

This is the thread. Inside I will emi

Answer 1

The structure of your example is more or less right: but you are mixing up the old-style signal-slot syntax with the new-style.

The signal definition should look like this:

class OptimThread(QtCore.QThread):
    signalUpdateMessageDialog = QtCore.pyqtSignal(int, str)

The signal should be emitted like this:

    self.signalUpdateMessageDialog.emit(
        time.time() - start, 'Initialising...')

And this is how the signal should be connected:

    self.optimThread.signalUpdateMessageDialog.connect(
        self.updateMessageDialog)

With the new-style syntax, there is never any need to use SIGNAL() or SLOT(), and it is never necessary to specify the C++ signature.

For further details, see New-style Signal and Slot Support in the PyQt4 reference.