def init ( self, parent ):
        # Initialize the trait handler to use:
        trait_handler = self.factory.trait_handler
        if trait_handler is None:
            trait_handler = self.object.base_trait( self.name ).handler
        self._trait_handler = trait_handler

        # Create a scrolled window to hold all of the list item controls:
        self.control = QtGui.QScrollArea()
        self.control.setFrameShape(QtGui.QFrame.NoFrame)
        self.control.setWidgetResizable(True)

        #Create a mapper to identify which icon button requested a contextmenu
        self.mapper = QtCore.QSignalMapper(self.control)

        # Create a widget with a grid layout as the container.
        self._list_pane = QtGui.QWidget()
        self._list_pane.setSizePolicy(QtGui.QSizePolicy.Expanding,
                                      QtGui.QSizePolicy.Expanding)
        layout = QtGui.QGridLayout(self._list_pane)
        layout.setAlignment(QtCore.Qt.AlignLeft | QtCore.Qt.AlignTop)
        layout.setContentsMargins(0, 0, 0, 0)

        # Remember the editor to use for each individual list item:
        editor = self.factory.editor
        if editor is None:
            editor = trait_handler.item_trait.get_editor()
        self._editor = getattr( editor, self.kind )

        # Set up the additional 'list items changed' event handler needed for
        # a list based trait. Note that we want to fire the update_editor_item
        # only when the items in the list change and not when intermediate
        # traits change. Therefore, replace "." by ":" in the extended_name
        # when setting up the listener.
        extended_name = self.extended_name.replace('.', ':')
        self.context_object.on_trait_change( self.update_editor_item,
                               extended_name + '_items?', dispatch = 'ui' )
        self.set_tooltip()

    #---------------------------------------------------------------------------
    #  Disposes of the contents of an editor:
    #---------------------------------------------------------------------------
Finishes initializing the editor by creating the underlying toolkit
dataset/ETHPy150Open enthought/traitsui/traitsui/qt4/list_editor.py/SimpleEditor.init