How to use the gaphor.misc.action.Action function in gaphor

print 'ref:', item
        menu_item_refs.append(weakref.ref(item))
        if item.get_submenu():
            connect_weakref(item.get_submenu())


class FileNewAction(Action):
    id = 'FileNew'
    stock_id = 'gtk-new'

    def execute(self):
        print 'New'

register_action(FileNewAction)

class FileQuitAction(Action):
    id = 'FileQuit'
    stock_id = 'gtk-quit'
    tooltip = 'Quit the application'

    def execute(self):
        window.destroy()
        #gtk.main_quit()

register_action(FileQuitAction)

class FileCheckAction(CheckAction):
    id = 'FileCheck'
    label = '_Check'
    #stock_id = 'gtk-save'
    tooltip = 'Check the checkbox'

accel = 'C-a'

    def init(self, window):
        self._window = window

    def update(self):
        diagram_tab = self._window.get_current_diagram_tab()
        self.sensitive = bool(diagram_tab)

    def execute(self):
        self._window.get_current_diagram_view().select_all()

register_action(SelectAllAction)


class DeselectAllAction(Action):
    id = 'EditDeselectAll'
    label = 'Des_elect All'
    accel = 'C-S-a'

    def init(self, window):
        self._window = window

    def update(self):
        diagram_tab = self._window.get_current_diagram_tab()
        self.sensitive = diagram_tab and len(diagram_tab.get_view().selected_items) > 0

    def execute(self):
        self._window.get_current_diagram_view().unselect_all()

register_action(DeselectAllAction, 'ItemSelect', 'EditDelete')

for item in self._new_items.values():
            item.move(10, 10)

        for item in self._new_items.values():
            item.postload()

        view.unselect_all()

        for item in self._new_items.values():
            view.select(view.find_view_item(item))

register_action(PasteAction, 'EditCopy')


class ZoomInAction(Action):
    id = 'ViewZoomIn'
    label = 'Zoom _In'
    accel = 'C-+'
    stock_id = 'gtk-zoom-in'
    tooltip = 'Zoom in'

    def init(self, window):
        self._window = window

    def update(self):
        diagram_tab = self._window.get_current_diagram_tab()
        self.sensitive = bool(diagram_tab)

    def execute(self):
        view = self._window.get_current_diagram_view()
        view.zoom(1.2)

class CloseAction(Action):
    id = 'FileClose'
    stock_id = 'gtk-close'
    tooltip='Close the diagram window'

    def init(self, window):
        self._window = window

    def execute(self):
        self._window.close()

register_action(CloseAction)


class QuitAction(Action):
    id = 'FileQuit'
    stock_id = 'gtk-quit'
    tooltip='Quit Gaphor'

    def init(self, window):
        self._window = window

    def execute(self):
        if self._window.ask_to_close():
            log.debug('Quiting gaphor...')
            self._window.close()
            del self._window
            gc.collect()

register_action(QuitAction)

def execute(self):
        element = self._window.get_tree_view().get_selected_element()
        diagram = self.element_factory.create(UML.Diagram)
        diagram.package = element

        diagram.name = '%s diagram' % element.name

        self._window.select_element(diagram)
        self.action_manager.execute('OpenModelElement')
        self.action_manager.execute('RenameModelElement')

register_action(CreateDiagramAction, 'SelectRow')


class DeleteDiagramAction(Action):
    id = 'DeleteDiagram'
    label = _('_Delete diagram')
    stock_id = 'gtk-delete'

    def init(self, window):
        self._window = window

    def update(self):
        element = self._window.get_tree_view().get_selected_element()
        self.sensitive = isinstance(element, UML.Diagram)

    def execute(self):
        diagram = self._window.get_tree_view().get_selected_element()
        assert isinstance(diagram, UML.Diagram)
        m = gtk.MessageDialog(None, gtk.DIALOG_MODAL, gtk.MESSAGE_QUESTION,
                              gtk.BUTTONS_YES_NO,

tooltip='Quit Gaphor'

    def init(self, window):
        self._window = window

    def execute(self):
        if self._window.ask_to_close():
            log.debug('Quiting gaphor...')
            self._window.close()
            del self._window
            gc.collect()

register_action(QuitAction)


class OpenEditorWindowAction(Action):
    id = 'OpenEditorWindow'
    label = _('_Editor')
    tooltip = 'Open the Gaphor Editor'

    def init(self, window):
        self._window = window

    def execute(self):
        from gaphor.ui.editorwindow import EditorWindow
        
        ew = EditorWindow()
        ew.construct()
        self._window.add_transient_window(ew)
        #self._window.set_message('Editor launched')

register_action(OpenEditorWindowAction)

register_action(SelectAction)


class FocusAction(Action):
    """Dummy action that is "called" when the selected items on the canvas
    change.
    """
    id = 'ItemFocus'

    def init(self, window):
        pass

register_action(FocusAction)


class DiagramDropAction(Action):
    """Dummy action that is "called" when a new item is placed on the canvas
    by means of Drag-and-drop.
    """
    id = 'ItemDiagramDrop'

    action_manager = inject('action_manager')

    def init(self, window):
        self._window = window
 
    def execute(self):
	self.action_manager.execute('CreateLinks')

register_action(DiagramDropAction)

register_action(TabChangeAction)

class UndoStackAction(Action):
    """
    Dummy action that triggers the undo and redo actions to update
    themselves.
    """
    id = 'UndoStack'
    
    def init(self, window):
        pass

register_action(UndoStackAction)

class UndoAction(Action):
    id = 'Undo'
    stock_id = 'gtk-undo'
    label = _('_Undo')
    tooltip = 'Undo the most recent changes'
    accel = 'C-z'

    # TODO: check if the diagram can undo.
    action_manager = inject('action_manager')

    def init(self, window):
        self._window = window

    def update(self):
        self.sensitive = get_undo_manager().can_undo()

    def execute(self):

def update(self):
        diagram_tab = self._window.get_current_diagram_tab()
        self.sensitive = bool(diagram_tab)
        self.active = diagram_tab and diagram_tab.get_canvas().get_property('grid_color') != diagram_tab.get_canvas().get_property('grid_bg') 

    def execute(self):
        tab = self._window.get_current_diagram_tab()
        if tab:
            canvas = tab.get_canvas()
            #canvas.set_property('grid_color', self.active and 255 or canvas.get_property('grid_bg'))

#register_action(ShowGridAction)


class ShowElementInTreeViewAction(Action):
    id = 'ShowElementInTreeView'
    label = 'S_how Element in Tree View'

    def init(self, window):
        self._window = window

    def update(self):
        diagram_tab = self._window.get_current_diagram_tab()
        self.sensitive = diagram_tab and diagram_tab.get_view().focused_item and \
			 diagram_tab.get_view().focused_item.subject

    def execute(self):
        tab = self._window.get_current_diagram_tab()
        if tab:
            view = tab.get_view()
	    fi = view.focused_item

elif pspec.name == 'sensitive':
            return self._sensitive
        else:
            raise AttributeError, 'Unknown property %s' % pspec.name

    def update(self):
        """update() is called by the ActionBroker after an other action
        has been changed.
        """
        pass

    def execute(self):
        pass


class CheckAction(Action):
    """CheckActions can be turned on and off.
    """

    __gproperties__ = {
        'active':      (gobject.TYPE_BOOLEAN, 'active',
                         '', True,
                         gobject.PARAM_READWRITE)
    }

    def __init__(self):
        Action.__init__(self)
        self._active = False

    active = property(lambda self: self._active,
                      lambda self, v: self.set_property('active', v))