The Code does not work successfully when the function is called

Question

I want to call method (close_ok()) in (main.py ) from method :close_call() in (module_b.py), but the Code does not work successfully when the function is called. can anyone help me with this problem? Here's the code for that :

@@@main.py

# -*- coding: utf-8 -*-
from PyQt4 import QtCore, QtGui
import sys
from GUI import Ui_MainWindow
class MainWindow(QtGui.QMainWindow,Ui_MainWindow):
    def __init__(self, parent=None):
        QtGui.QWidget.__init__(self, parent)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        from module_c import class_c
        global b 
        b=class_c()
        QtCore.QObject.connect(self.ui.pushButton, QtCore.SIGNAL("clicked()"), b.close_call )
    def close_ok(self):
        ##But it can not be done successfully.
        self.close()


if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    global myapp
    myapp = MainWindow()
    myapp.show()
    sys.exit(app.exec_())

@@@ module_b.py

class class_c (object):
     def __init__(self, parent=None):
       self.parent=parent

 ### I want call method (close_ok()) in (menu class) from here    
     def close_call (self):
          from main import MainWindow
          t=MainWindow()
          t.close_ok()

@@@GUIpy

# -*- coding: utf-8 -*-


from PyQt4 import QtCore, QtGui
try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s
try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)
class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        super(Ui_MainWindow, self).__init__()
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(800, 600)
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.pushButton = QtGui.QPushButton(self.centralwidget)
        self.pushButton.setGeometry(QtCore.QRect(340, 110, 75, 23))
        self.pushButton.setObjectName(_fromUtf8("pushButton"))
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtGui.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 21))
        self.menubar.setObjectName(_fromUtf8("menubar"))
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QtGui.QStatusBar(MainWindow)
        self.statusbar.setObjectName(_fromUtf8("statusbar"))
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))
        self.pushButton.setText(_translate("MainWindow", "PushButton", None))

Answer 1

you use diffrent instances of the class MainWindow() so it wont close the original window, change it like this:

class MainWindow(QtGui.QMainWindow,Ui_MainWindow):
    def __init__(self, parent=None):
        QtGui.QWidget.__init__(self, parent)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        from module_c import class_c
        global b 
        b=class_c(self) #NOTICE THE CHANGE HERE
        QtCore.QObject.connect(self.ui.pushButton, QtCore.SIGNAL("clicked()"), b.close_call )

    def close_ok(self):
        self.close()

and change module b to do:

class class_c (object):
 def __init__(self, parent=None):
   self.parent=parent

 def close_call (self):
      from main import MainWindow
      self.parent.close_ok()# NOTICE THIS CHANGE, parent is now the original MainWindow

this way you pass your original MainWindow instancce to class_c and use it, instead of creating a new instance