python - PyQt: How to switch widgets in QStackedWidget

Question

I have two buttons (wgtbtnA & wgtbtnB) placed on two different pages (page1 and page2, respectively) inside a parent object (objectName: stackedWidget). My dilemma is this: when I run the code, the arrows don't display in PyQt. Why? How do I alternate from page1 to page2 and vice-versa?

Here is an image of runtime, which conveys what I am asking for:

Qt Designer:

I'd like to keep those small back arrows.

Below is my code:

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

# Form implementation generated from reading ui file 'stackedWidget.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!

from PyQt4 import QtCore, QtGui
import sys
import os


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(512, 304)
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.stackedWidget = QtGui.QStackedWidget(self.centralwidget)
        self.stackedWidget.setGeometry(QtCore.QRect(150, 60, 161, 121))
        self.stackedWidget.setObjectName(_fromUtf8("stackedWidget"))
        self.page = QtGui.QWidget()
        self.page.setObjectName(_fromUtf8("page"))
        self.wgtMainWindow = QtGui.QPushButton(self.page)
        self.wgtMainWindow.setGeometry(QtCore.QRect(50, 50, 75, 23))
        self.wgtMainWindow.setObjectName(_fromUtf8("wgtMainWindow"))
        self.stackedWidget.addWidget(self.page)
        self.page_2 = QtGui.QWidget()
        self.page_2.setObjectName(_fromUtf8("page_2"))
        self.wgtbtnB = QtGui.QPushButton(self.page_2)
        self.wgtbtnB.setGeometry(QtCore.QRect(50, 50, 75, 23))
        self.wgtbtnB.setObjectName(_fromUtf8("wgtbtnB"))
        self.stackedWidget.addWidget(self.page_2)
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtGui.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 512, 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)
        self.stackedWidget.setCurrentIndex(1)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))
        self.wgtMainWindow.setText(_translate("MainWindow", "Widget A", None))
        self.wgtbtnB.setText(_translate("MainWindow", "Widget B", None))


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

if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    mySW = ControlMainWindow()
    mySW.show()
    sys.exit(app.exec_())

Answer 1

You could use the buttons to change the page: {your QPushButton}.clicked.connect(lambda: {your QStackedWidget}.setCurrentIndex({another page}))

By Example:

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

# Form implementation generated from reading ui file 'stackedWidget.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!

from PyQt4 import QtCore, QtGui
import sys


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(512, 304)
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.stackedWidget = QtGui.QStackedWidget(self.centralwidget)
        self.stackedWidget.setGeometry(QtCore.QRect(150, 60, 161, 121))
        self.stackedWidget.setObjectName(_fromUtf8("stackedWidget"))
        self.page = QtGui.QWidget()
        self.page.setObjectName(_fromUtf8("page"))
        self.wgtMainWindow = QtGui.QPushButton(self.page)
        self.wgtMainWindow.setGeometry(QtCore.QRect(50, 50, 75, 23))
        self.wgtMainWindow.setObjectName(_fromUtf8("wgtMainWindow"))
        self.stackedWidget.addWidget(self.page)
        self.page_2 = QtGui.QWidget()
        self.page_2.setObjectName(_fromUtf8("page_2"))
        self.wgtbtnB = QtGui.QPushButton(self.page_2)
        self.wgtbtnB.setGeometry(QtCore.QRect(50, 50, 75, 23))
        self.wgtbtnB.setObjectName(_fromUtf8("wgtbtnB"))
        self.stackedWidget.addWidget(self.page_2)
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtGui.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 512, 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)
        self.stackedWidget.setCurrentIndex(1)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))
        self.wgtMainWindow.setText(_translate("MainWindow", "Widget A", None))
        self.wgtbtnB.setText(_translate("MainWindow", "Widget B", None))


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

        self.ui.wgtbtnB.clicked.connect(lambda : self.ui.stackedWidget.setCurrentIndex(0))
        self.ui.wgtMainWindow.clicked.connect(lambda : self.ui.stackedWidget.setCurrentIndex(1))

if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    mySW = ControlMainWindow()
    mySW.show()
    sys.exit(app.exec_())

Start app:

after clicked button:

after clicked another button: