Qt catch closeEvent example

qt_exit.py

#!/usr/bin/python
# -*- coding: utf-8 -*-

import sys
from PyQt4 import QtGui


class MyWindow(QtGui.QMainWindow):
    def closeEvent(self, event):
        if self.showDialog():
            event.accept()
        else:
            event.ignore()

    def showDialog(self):
        msg = QtGui.QMessageBox()
        msg.setText('Do you really want to Exit?')
        msg.setStandardButtons(QtGui.QMessageBox.Ok | QtGui.QMessageBox.Cancel)
        retval = msg.exec_()
        if retval ==  QtGui.QMessageBox.Ok:
            return True
        else:
            return False


def main():
    app = QtGui.QApplication(sys.argv)

    w = MyWindow()
    w.resize(250, 150)
    w.move(300, 300)
    w.setWindowTitle('Exit Test')
    w.show()
    
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()