Member Avatar for soibac

Hi all,

I have 2 form and a main.py in the project: ffrend.py and fmain.py

main.py:

from PyQt4 import QtCore, QtGui
from fmain import *

if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    MainWindow = QtGui.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    app.exec_()

fmain.py (there is a button to execute the following function)

def friendNetWork(self):
        form = QtGui.QWidget()
        ui = Ui_ffriend()
        ui.setupUi(form)
        form.show()
        app.exec_()

When I run main.py, the fmain form is shown. When I click the button on fmain form, the friendNetWork will be executed and create another widget.

But...I received the error in console :(...And the python is hang :(

QCoreApplication::exec: The event loop is already running
QCoreApplication::exec: The event loop is already running
QCoreApplication::exec: The event loop is already running
QCoreApplication::exec: The event loop is already running

Please help me with this

  • 6 Contributors
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  • Latest Post Latest Post by RespectedCow
Member Avatar for HiHe

the line
app.exec_()
starts the event loop and you have two of those lines

Member Avatar for soibac

Actually, I tried to remove app.exec_() in the friendNetWork function.

But this made the ffriend display and exit immediately.

Member Avatar for Gribouillis

see this thread. It looks like the same issue.

Member Avatar for soibac

Hi Gribouillis,

Thanks for your reply.

I changed my solution a litte bit:

  • Create a reference for ffriend in fmain
  • Remove app.exec_() in ffriend

Now the ffriend can be displayed without app.exec_().

But another problem occured, I can't interact with ffriend. There is a button on ffriend will do something as printing a message. Now, I clicked the button but nothing printed :'(

def setupUi(self, ffriend):
    ### Code generated from Pyuic
    ...
    self.btnphantich = QtGui.QPushButton(ffriend)
    ...
    QtCore.QObject.connect(self.btnphantich, QtCore.SIGNAL(_fromUtf8("clicked()")), self.printhello)
    QtCore.QMetaObject.connectSlotsByName(ffriend)

def printhello(self):
    print "hello world!" ### No hello world here although it can be printed with app.exec_()

Please gui me or point me what to read next.

Thank you!

Member Avatar for vikky_1694

Guys, I am facing same issue, help me how you resolve this topic?

commented: See above solution for this problem. +0
Member Avatar for Juan_25

I have the same problem , please help D:

Member Avatar for RespectedCow

I did this with qsystemtray and the context menu didn't work.

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