在 pyqt4 中退出 window 并打开另一个的正确方法？

Question

我有两个 windows，（让它们命名为 X 和 Y。当 X 收到信号时，它应该自杀，运行 window Y。

我是怎么做到的：

尝试通过调用 exit 和东西退出 window X 并像菜鸟一样启动 window Y。（出现分段错误并且循环已经运行宁东西）
尝试将同一个应用程序传递给另一个应用程序window，但仍然没有成功。

我的 X 和 Y 看起来像这样：

This is X which calls Y

from PyQt4 import QtCore, QtGui
import sqlite3,hashlib,time
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 __init__(self):
        self.server = sqlite3.connect('ems.db')
        self.cursor = self.server.cursor()
    def dummy(self,*args):
        self.close()
        #close("Kallu")

    def setupUi(self, MainWindow):
        # A button calls dummy here
        # Other boring stuff

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

    def retranslateUi(self, MainWindow):
        #Boring

import sys
app = QtGui.QApplication(sys.argv)
MainWindow = QtGui.QMainWindow()
ui = Ui_MainWindow()
ui.setupUi(MainWindow)

def close(user): #Routine for closing window
    app.closeAllWindows()
    app.quit()
    app.exit()
    import y #here i import Y

    y.main(app)  #Dosent works even if i pass the app as i have to run
    #app again there but it'll show already running

if __name__ == "__main__":
    MainWindow.show()
    sys.exit(app.exec_())

This is the Y code

import time
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):
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(746, 503)
        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

import sys
def main(user):
    app = QtGui.QApplication(sys.argv)
    MainWindow = QtGui.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

我不需要你修改代码，而是让我了解如何做以及它为何有效？

Answer 1

一个程序不是一组文件，而是一组相互作用的对象，所以想法是两个 windows 在同一个地方，关闭时另一个打开。另一方面，PyQt 建议不要修改 Qt Designer 生成的 class，而是创建一个新的 class 继承适当的小部件并使用初始 class 作为界面（有关更多信息，请阅读 the docs).

x.py

from PyQt4 import QtCore, QtGui

from y import YMainWindow

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):
        self.button = QtGui.QPushButton("Close")
        MainWindow.setCentralWidget(self.button)
        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        pass

class XMainWindow(QtGui.QMainWindow, Ui_MainWindow):
    closed = QtCore.pyqtSignal()

    def __init__(self, parent=None):
        super(XMainWindow, self).__init__(parent)
        self.setupUi(self)
        self.button.clicked.connect(self.dummy)

    @QtCore.pyqtSlot()
    def dummy(self):
        self.closed.emit()
        self.close()

import sys

def main():
    app = QtGui.QApplication.instance()
    if app is None:
        app = QtGui.QApplication(sys.argv)
    wx = XMainWindow()
    wy = YMainWindow()
    wx.closed.connect(wy.show)
    wx.show()
    return app.exec_()

if __name__ == "__main__":
    sys.exit(main())

y.py

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):
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(746, 503)
        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        pass

class YMainWindow(QtGui.QMainWindow, Ui_MainWindow):
    def __init__(self, parent=None):
        super(YMainWindow, self).__init__(parent)
        self.setupUi(self)

在 pyqt4 中退出 window 并打开另一个的正确方法？

Proper method to exit a window and open another one in pyqt4?

pyqt4

python-3.x