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

 '''

 Created on Sep 13, 2018

 @author: SaShuangYiBing

 '''

 import sys

 from PyQt5.QtWidgets import QApplication,QWidget,QMessageBox,QPushButton

 from PyQt5.QtCore import QCoreApplication

 class New_test(QWidget):

     def __init__(self):

         super().__init__()

         self.initUI()

     def initUI(self):

         qbtn = QPushButton('Quit',self) # 创建了一个按钮。按钮是一个QPushButton类的实例。

         # 构造方法的第一个参数是显示在button上的标签文本。第二个参数是父组件。

         # 父组件是Example组件，它继承了QWiget类。

         qbtn.clicked.connect(QCoreApplication.instance().quit)

         qbtn.resize(qbtn.sizeHint())

         qbtn.move(100,50)

         self.setGeometry(300,300,250,150)

         self.setWindowTitle('Message box')

         self.show()

     def closeEvent(self, event):

         reply = QMessageBox.question(self, 'Message', 'Are you want to quit?', QMessageBox.Yes | QMessageBox.No,QMessageBox.Yes)

         if reply == QMessageBox.Yes:

             event.accept()

         else:

             event.ignore()

 if __name__ == "__main__":

     app = QApplication(sys.argv)

     ex = New_test()

     sys.exit(app.exec_())