Segfault after signal emit

abieler

I am trying to switch from pyqt4 to pyside and having trouble when emitting a signal from a worker thread.
the result is a segmentation fault. The same thing works for pyt4.
the gui consists of one button which starts the worker thread and should emit a signal when done.
the worker_thread is started after clicking the button, but the segfault appears when emitting the signal.
(this is meant to be a generic example, not (yet) a useful application...)

Thanks for the help!

@
import sys

from PySide import QtCore as QTC
from PySide import QtGui as QTG
import ui_signalTest_pyside as myUi

'''
from PyQt4 import QtCore as QTC
from PyQt4 import QtGui as QTG
import ui_signalTest_pyqt as myUi
'''

class Window(QTG.QWidget,myUi.Ui_Form):
def init(self, parent = None):
super(Window, self).init(parent)
self.setupUi(self)

    self.worker_thread = Worker()
    self.connect(self.worker_thread,QTC.SIGNAL("doSomething"),\
    self.myFunc)
    self.connect(self.pushButton, QTC.SIGNAL("clicked()"),\
    self.startThread)


def startThread(self):
    self.worker_thread.start()


def myFunc(self,msg):
    print 'signal recieved:', msg

class Worker(QTC.QThread):

def __init__(self, parent = None):
    QTC.QThread.__init__(self,parent)


def run(self):
    N = 10000
    for i in range(N):
        for j in range(N):
            i+j

    msg = 'loop finished'
    self.emit(QTC.SIGNAL("doSomething"),msg)

app = QTG.QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())

@

lcasassa

I am having the same problem, did you find a solution? Thanks.

abieler

yes i did find a solution:
@
import sys

from PySide import QtCore as QTC
from PySide import QtGui as QTG
import ui_signalTest_pyside as myUi

'''
from PyQt4 import QtCore as QTC
from PyQt4 import QtGui as QTG
import ui_signalTest_pyqt as myUi
'''

class Window(QTG.QWidget,myUi.Ui_Form):
def init(self, parent = None):
super(Window, self).init(parent)
self.setupUi(self)

    self.worker_thread = Worker()
    self.connect(self.pushButton,QTC.SIGNAL("clicked()"),
                      self.startThread)
    
    self.worker_thread.mySignal.connect(self.myFunc,
                      QTC.Qt.QueuedConnection)

def startThread(self):
    self.worker_thread.start()


def myFunc(self,msg):
    print 'signal recieved:', msg

class Worker(QTC.QThread):

mySignal = QTC.Signal(str)
    
def __init__(self, parent = None):
    QTC.QThread.__init__(self,parent)


def run(self):
    N = 10000
    for i in range(N):
        for j in range(N):
            i+j

    msg = 'loop finished'
    self.mySignal.emit(msg)

app = QTG.QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())
@

abieler

It would be good if someone more knowledgeable than me could comment on my first attempt that ends in a segfault. is this a bug in pyside or is it not intended to be used like that?