title: Put a QToolBar in a QWidget instead of QMainWindow
body: <p>I am trying to put a QToolBar on a layout of a QWidget instead of QMainWindow. On QMainWindow and QWidget is working fine, but when i try to add it on a layout first, is not. Am I doing something wrong? Is it possible? Here is my code:</p>
  
  <pre><code>from PyQt4 import QtGui, QtCore
  import sys
  
  
  img = '../../Images/logo.png'
  
  
  if __name__ == '__main__':
      app = QtGui.QApplication(sys.argv)
  
  
      mainWin = QtGui.QMainWindow()    
  
      widget = QtGui.QWidget()    
      hLayout = QtGui.QHBoxLayout()
  
      '''ToolBar On main Window '''    
  
      basicToolBar = mainWin.addToolBar('Basic')
      basicToolBar.addAction(QtGui.QAction('Test', mainWin))
  #    basicToolBar.addAction(QtGui.QAction(QtGui.QIcon(img), 'Test', mainWin))
  
  #    mainWin.show()
  
  
      '''ToolBar On Widget '''
  
      # Case 1: Set widget as parent
  #    widgetToolBar = QtGui.QToolBar(widget)
  #    widgetToolBar.addAction(QtGui.QAction('Test', widget))
  #    widgetToolBar.addAction(QtGui.QAction(QtGui.QIcon(img), QtGui.QAction('Test', widget))
  
      # Case 2: Set toolBat on a layout
      widgetToolBar = QtGui.QToolBar()
      widgetToolBar.addAction(QtGui.QAction('Test', None))
  #   widgetToolBar.addAction(QtGui.QAction(QtGui.QIcon(img), 'Test', None))    
      hLayout.addWidget(widgetToolBar)  
      widget.setLayout(hLayout)
  
      widget.show()
  
      # Run 
      sys.exit(app.exec_())
  </code></pre>