Enthought TraitsUI ValueEditor: Выбор значений

Question

Я использую ValueEditor (source, docs) для просмотра вложенного объекта HasTraits и заметил, что получить выбранное значение из этого редактора не так просто, как это было бы для ListEditor, например ,

Я даже пытался просто редактирование модуля на моем сайте-пакетах без толка:

#------------------------------------------------------------------------------ 
# 
# Copyright (c) 2006, Enthought, Inc. 
# All rights reserved. 
# 
# This software is provided without warranty under the terms of the BSD 
# license included in enthought/LICENSE.txt and may be redistributed only 
# under the conditions described in the aforementioned license. The license 
# is also available online at http://www.enthought.com/licenses/BSD.txt 
# 
# Thanks for using Enthought open source! 
# 
# Author: David C. Morrill 
# Date: 01/05/2006 
# 
#------------------------------------------------------------------------------ 

""" Defines the tree-based Python value editor and the value editor factory. 
""" 

#------------------------------------------------------------------------------- 
# Imports: 
#------------------------------------------------------------------------------- 

from __future__ import absolute_import 

from traits.api import Instance, Int, false 

from .tree_editor import TreeEditor 
from ..view import View 
from ..item import Item 

from ..value_tree import RootNode, value_tree_nodes 

from ..editor_factory import EditorFactory 

from ..editor import Editor 

#------------------------------------------------------------------------------- 
# 'SimpleEditor' class: 
#------------------------------------------------------------------------------- 

class _ValueEditor (Editor): 
    """ Simple style of editor for values, which displays a tree. 
    """ 

    #--------------------------------------------------------------------------- 
    # Trait definitions: 
    #--------------------------------------------------------------------------- 

    # Is the editor read only? 
    readonly = false 

    # The root node of the value tree 
    root = Instance(RootNode) 

    # Is the value editor scrollable? This values overrides the default. 
    scrollable = True 

    #--------------------------------------------------------------------------- 
    # Finishes initializing the editor by creating the underlying toolkit 
    # widget: 
    #--------------------------------------------------------------------------- 

    def init (self, parent): 
     """ Finishes initializing the editor by creating the underlying toolkit 
      widget. 
     """ 
     self.update_editor() 
     editor = TreeEditor(
      auto_open = self.factory.auto_open, 
      hide_root = True, 
      editable = False, 
      nodes  = value_tree_nodes, 
      selection_mode='single', # <------CHANGED HERE 
      selected='current_selection' 
     ) 
     self._ui = self.edit_traits(parent = parent, view = 
         View(
          Item('root', 
           show_label = False, 
           editor  = editor 
          ), 
          kind = 'subpanel' 
         ) 
        ) 
     self._ui.parent = self.ui 
     self.control = self._ui.control 

    def _selected_changed(self): 
     print 'selected changed' 

    def _current_selection_changed(self): 
     print 'current changed' 

    #--------------------------------------------------------------------------- 
    # Updates the editor when the object trait changes external to the editor: 
    #--------------------------------------------------------------------------- 

    def update_editor (self): 
     """ Updates the editor when the object trait changes external to the 
      editor. 
     """ 
     self.root = RootNode(name  = '', 
           value = self.value, 
           readonly = self.readonly) 

    #--------------------------------------------------------------------------- 
    # Disposes of the contents of an editor: 
    #--------------------------------------------------------------------------- 

    def dispose (self): 
     """ Disposes of the contents of an editor. 
     """ 
     self._ui.dispose() 

     super(_ValueEditor, self).dispose() 

    #--------------------------------------------------------------------------- 
    # Returns the editor's control for indicating error status: 
    #--------------------------------------------------------------------------- 

    def get_error_control (self): 
     """ Returns the editor's control for indicating error status. 
     """ 
     return self._ui.get_error_controls() 

#------------------------------------------------------------------------------- 
# 'ToolkitEditorFactory' class: 
#------------------------------------------------------------------------------- 

class ToolkitEditorFactory (EditorFactory): 
    """ Editor factory for tree-based value editors. 
    """ 

    #--------------------------------------------------------------------------- 
    # Trait definitions: 
    #--------------------------------------------------------------------------- 

    # Number of tree levels to automatically open 
    auto_open = Int(2) 

# Define the ValueEditor class. 
ValueEditor = ToolkitEditorFactory 

#--EOF------------------------------------------------------------------------- 

Answer 1

Если у вас есть вложенный HasTraits объекта, как правило, вы хотите использовать InstanceEditor.

from traits.api import HasTraits, Str, Instance 
from traitsui.api import View, InstanceEditor, Item 


class Foo(HasTraits): 
    name_1 = Str("foo_1") 
    name_2 = Str("foo_2") 

class Bar(HasTraits): 
    my_foo = Instance(Foo,()) 

    traits_view = View(
     Item('my_foo', 
      style='custom', 
      editor=InstanceEditor(), 
     ), 
    ) 


if __name__ == '__main__': 
    f = Bar() 
    f.configure_traits() 

Вы можете дополнительно указать атрибут view, передавая traitsUIView объекта.