title: Python: How to to query a current Tab from QTabWidget
body: <p>A simple dialog with three tabs: 'Tab_01', 'Tab_02' and 'Tab_03'.
  Pressing 'What Tab?' button should print what tab is currently active.
  How to achieve it? (example code posted below):</p>
  
  <p><img src="https://i.stack.imgur.com/KaKIB.png" alt="enter image description here"></p>
  
  <pre><code>from PyQt4 import QtGui, QtCore
  import sys, os
  
  
  class Dialog_01(QtGui.QMainWindow):
      def __init__(self):
          super(QtGui.QMainWindow,self).__init__()
  
          mainWidget=QtGui.QWidget()
          self.setCentralWidget(mainWidget)
          mainLayout = QtGui.QVBoxLayout()
          mainWidget.setLayout(mainLayout)
  
          self.tabWidget = QtGui.QTabWidget()
          mainLayout.addWidget(self.tabWidget)
  
          self.tabWidget.connect(self.tabWidget, QtCore.SIGNAL("currentChanged(int)"), self.tabSelected)
  
          myBoxLayout = QtGui.QVBoxLayout()
          self.tabWidget.setLayout(myBoxLayout)
  
          self.tabWidget.addTab(QtGui.QWidget(),'Tab_01')
          self.tabWidget.addTab(QtGui.QWidget(),'Tab_02')
          self.tabWidget.addTab(QtGui.QWidget(),'Tab_03')          
  
  
          ButtonBox = QtGui.QGroupBox() 
          ButtonsLayout = QtGui.QHBoxLayout()
          ButtonBox.setLayout(ButtonsLayout)
  
          Button_01 = QtGui.QPushButton("What Tab?")
          ButtonsLayout.addWidget(Button_01)
          Button_01.clicked.connect(self.whatTab)
  
          mainLayout.addWidget(ButtonBox)
  
  
      def tabSelected(self, arg=None):
          print '\n\t tabSelected():', arg
  
      def whatTab(self):
          print '\n\t current Tab:', '?'
  
  
  if __name__ == '__main__':
      app = QtGui.QApplication(sys.argv)
      dialog_1 = Dialog_01()
      dialog_1.show()
      dialog_1.resize(480,320)
      sys.exit(app.exec_())
  </code></pre>