[PyGUI] Failed when communicating between threads

[pythonisse]

Hi everybody,

I am trying to display an image on the window, but when I try it, I got this error:
"QPixmap: It is not safe to use pixmaps outside the GUI thread"

As you can see I am using two threads: one for the GUI and another one of the APP logic. The new image path file is generated in the app logic thread which should be sent to the GUI thread.
For this reason, I decided to use the Signal & slots communication mechanism.

I put the basic logic of my still-to-finish solution into small pieces to illustrate it, so you can run it and give me a hand if you have time.

The program basically shows an internal value for each thread every x seconds, and every time it is changed on LOGIC class it should be changed on GUI class too - just an example of what I would like to do with the final widget that can be only changed form its own thread:

import threading
from PyQt4.QtCore import QObject, SIGNAL
import time
import random



class LOGIC (threading.Thread, QObject):

        def __init__(self):
                QObject.__init__(self)
                threading.Thread.__init__(self)
                self.id = "LOG"
                self.value = 0

        def run(self):
                while True:
                        self.value = random.randint(1, 10)
                        print ("[" + self.id + "] value = " + str(self.value))
                        self.on_value_changed(self.value)
                        time.sleep(4)

        def on_value_changed(self, value):
                print ("[" + self.id + "] Running on_value_changed()")
                self.emit(SIGNAL('changeThisPlease(int)'), int(self.value))



class GUI (threading.Thread, QObject):

        def __init__(self):
                QObject.__init__(self)
                threading.Thread.__init__(self)
                self.id = "GUI"
                self.value = 0

        def run(self):
                while True:
                        print ("[" + self.id + "] value = " + str(self.value))
                        time.sleep(1)

        def on_GUI_changeValue(self, value):
                print ("[" + self.id + "] Running on_GUI_changeValue()")
                self.value = int(value)


if __name__ == '__main__':

        myLogic = LOGIC()
        myLogic.start()

        myGui = GUI()
        myGui.start()

        myLogic.connect(myLogic, SIGNAL("changeThisPlease(int)"), myGui.on_GUI_changeValue)

The GUI thread always shows the initial value, so it's never changed by the signal emitted by LOGIC, what am I doing wrong?
Could you please give me a hand?

Thanks so much for reading