Python：关闭QMainWindow对话框后如何接近（或退出）Python进程

Question

这里有两个.py文件，它们放在同一个文件夹里：

dialog_01.py and dialog_02.py

这两个文件是完全一样的。它们都创建了一个简单的QMainWindow对话框，里面有两个按钮：'确定'和'取消'。

点击'确定'按钮会关闭当前打开的对话框，并打开另一个对话框。所以如果点击Dialog_01的'确定'按钮，Dialog_01就会关闭，然后Dialog_02就会打开。如果点击Dialog_02的'确定'按钮，那么Dialog_02就会关闭，Dialog_01又会打开，依此类推。

编辑后的问题：

关闭对话框后，Python进程仍然在后台运行（可以在OSX的活动监视器或Windows的任务管理器中看到）。

怎么确保在关闭对话框后，Python进程也被终止？

dialog_01.py

import sys, os
from PyQt4 import QtCore, QtGui    
if 'app' not in globals().keys(): app = QtGui.QApplication(sys.argv)

class Dialog_01(QtGui.QMainWindow):
    def __init__(self):
        super(QtGui.QMainWindow,self).__init__()

        myQWidget = QtGui.QWidget()
        myBoxLayout = QtGui.QVBoxLayout()       

        Cancel_button = QtGui.QPushButton("Cancel")
        Cancel_button.clicked.connect(self.Cancel)      
        myBoxLayout.addWidget(Cancel_button) 


        Button_01 = QtGui.QPushButton("Press to close this dialog and open Dialog 02")
        Button_01.clicked.connect(self.callAnotherQMainWindow)
        myBoxLayout.addWidget(Button_01)        

        myQWidget.setLayout(myBoxLayout)
        self.setCentralWidget(myQWidget)
        self.setWindowTitle('Dialog 01')

    def callAnotherQMainWindow(self):
        from dialog_02 import Dialog_02
        self.close()
        self.dialog_02 = Dialog_02()
        self.dialog_02.show()
        self.dialog_02.raise_()

    def Cancel(self):
        self.close()

    def closeEvent(self):
        self.deleteLater()



if __name__ == '__main__':
    dialog_1 = Dialog_01()
    dialog_1.show()
    dialog_1.resize(480,320)
    sys.exit(app.exec_())

dialog_02.py

import sys, os
from PyQt4 import QtCore, QtGui    
if 'app' not in globals().keys(): app = QtGui.QApplication(sys.argv)

class Dialog_02(QtGui.QMainWindow):
    def __init__(self):
        super(QtGui.QMainWindow,self).__init__()

        myQWidget = QtGui.QWidget()
        myBoxLayout = QtGui.QVBoxLayout()

        Cancel_button = QtGui.QPushButton("Cancel")
        Cancel_button.clicked.connect(self.Cancel)      
        myBoxLayout.addWidget(Cancel_button) 


        Button_02 = QtGui.QPushButton("Press to close this dialog 02 and re-open Dialog 01")
        Button_02.clicked.connect(self.callAnotherQMainWindow)
        myBoxLayout.addWidget(Button_02)

        myQWidget.setLayout(myBoxLayout)
        self.setCentralWidget(myQWidget)
        self.setWindowTitle('Dialog 02')

    def callAnotherQMainWindow(self):
        from dialog_01 import Dialog_01
        self.close()
        self.dialog_01 = Dialog_01()
        self.dialog_01.show()
        self.dialog_01.raise_()

    def Cancel(self):
        self.close()

    def closeEvent(self):
        self.deleteLater()


if __name__ == '__main__':
    dialog_2 = Dialog_02()
    dialog_2.show()
    dialog_2.resize(480,320)
    sys.exit(app.exec_())

Answer 1

这里是一个可以运行的例子。

dialog_01.py

import sys, os
from PyQt4 import QtCore, QtGui  

class Dialog_01(QtGui.QMainWindow):
    def __init__(self):
        super(QtGui.QMainWindow,self).__init__()

        myQWidget = QtGui.QWidget()
        myBoxLayout = QtGui.QVBoxLayout()       

        Cancel_button = QtGui.QPushButton("Cancel")
        Cancel_button.clicked.connect(self.Cancel)      
        myBoxLayout.addWidget(Cancel_button) 


        Button_01 = QtGui.QPushButton("Press to close this dialog and open Dialog 02")
        Button_01.clicked.connect(self.callAnotherQMainWindow)
        myBoxLayout.addWidget(Button_01)        

        myQWidget.setLayout(myBoxLayout)
        self.setCentralWidget(myQWidget)
        self.setWindowTitle('Dialog 01')

    def callAnotherQMainWindow(self):
        from dialog_02 import Dialog_02
        self.close()
        self.dialog_02 = Dialog_02()
        self.dialog_02.show()
        self.dialog_02.raise_()

    def Cancel(self):
        self.close()

    # def closeEvent(self, event):
    #     self.deleteLater()



if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    dialog_1 = Dialog_01()
    dialog_1.show()
    dialog_1.resize(480,320)
    sys.exit(app.exec_())

dialog_02.py

import sys, os
from PyQt4 import QtCore, QtGui    

class Dialog_02(QtGui.QMainWindow):
    def __init__(self):
        super(QtGui.QMainWindow,self).__init__()

        myQWidget = QtGui.QWidget()
        myBoxLayout = QtGui.QVBoxLayout()

        Cancel_button = QtGui.QPushButton("Cancel")
        Cancel_button.clicked.connect(self.Cancel)      
        myBoxLayout.addWidget(Cancel_button) 


        Button_02 = QtGui.QPushButton("Press to close this dialog 02 and re-open Dialog 01")
        Button_02.clicked.connect(self.callAnotherQMainWindow)
        myBoxLayout.addWidget(Button_02)

        myQWidget.setLayout(myBoxLayout)
        self.setCentralWidget(myQWidget)
        self.setWindowTitle('Dialog 02')

    def callAnotherQMainWindow(self):
        from dialog_01 import Dialog_01
        self.close()
        self.dialog_01 = Dialog_01()
        self.dialog_01.show()
        self.dialog_01.raise_()

    def Cancel(self):
        self.close()

    # def closeEvent(self, event):
    #     self.deleteLater()


if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    dialog_2 = Dialog_02()
    dialog_2.show()
    dialog_2.resize(480,320)
    sys.exit(app.exec_())

Answer 2

重写你的QtGui.QMainWindow类中的closeEvent()函数，像下面这样：

def closeEvent(self, event):
    self.deleteLater()

这样做似乎有效：

去掉这个：

if 'app' not in globals().keys(): app = QtGui.QApplication(sys.argv)

还有这个：

if __name__ == '__main__':
    dialog_2 = Dialog_02()
    dialog_2.show()
    dialog_2.resize(480,320)
    sys.exit(app.exec_())

...从dialog2文件中去掉这些就解决了问题。