title: PyQt: How to switch widgets in QStackedWidget
body: <p>I have two buttons (<em>wgtbtnA</em> &amp; <em>wgtbtnB</em>) placed on two different pages (<em>page1</em> and <em>page2</em>, respectively) inside a parent object (objectName: <em>stackedWidget</em>). 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? </p>
  
  <p>Here is an image of runtime, which conveys what I am asking for:</p>
  
  <p><img src="https://i.stack.imgur.com/TPSm2.jpg" alt="btnwgtB"></p>
  
  <p>Qt Designer:</p>
  
  <p><img src="https://i.stack.imgur.com/x4RnM.jpg" alt="btnwgtA"></p>
  
  <p>I'd like to keep those small back arrows.</p>
  
  <p>Below is my code:</p>
  
  <pre><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_())
  </code></pre>