考虑特征UI，将值动态添加到CheckListEditor的“值”特征

Question

How can I add 'values' dynamically to the CheckListEditor?
But instead of static 'values', I have to get it dynamically from Bclass options attr.

from enthought.traits.api import HasTraits, Instance, Str
from enthought.traits.ui.api import View, Item, CheckListEditor

class Bclass:
    options = ['one', 'two']

class Aclass(HasTraits):
    bclass = Instance(Bclass)
    abc = Str
    view = View(
        Item(name='abc', editor=CheckListEditor(values=['one', 'two']) ),
        style='simple',
        )

Answer 1

Instead of giving to the CheckListEditor a list of values , you can give it the name of the trait containing the values:

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

class Bclass(HasTraits):
    options = List(['one', 'two'])

class Aclass(HasTraits):
    bclass = Instance(Bclass)
    abc = Str

    traits_view = View(
        Item(name='abc', editor=CheckListEditor(name='object.bclass.options')),
    )

b = Bclass()
a = Aclass(bclass=b)
a.configure_traits()

In the example, 'object.bclass.options' means: the traits called options which is an attribute of the trait called bclass in the context object , ie, the namespace of the current object. The context is only necessary when using the name of a trait in another class.

Update following poster's comment:

In a comment, the poster asked what would happen if Bclass is not an HasTraits class, and/or options is a dictionary.

If Bclass is not a HasTraits class, you won't be able to respond to changes in the dictionary content, so I would do this:

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

class Bclass(object):
    options = {'one': 1, 'two': 2}

class Aclass(HasTraits):
    bclass = Instance(Bclass)
    abc = Str

    def default_traits_view(self):
        options = self.bclass.options.keys()
        view = View(
            Item(name='abc', editor=CheckListEditor(values=options)),
        )
        return view

The default_traits_view method is called to create the TraitsUI view dynamically.

If Bclass is a HasTraits class, then you can do better:

from traits.api import HasTraits, Instance, Str, Property, Dict
from traitsui.api import View, Item, CheckListEditor

class Bclass(HasTraits):
    options = Dict({'one': 1, 'two': 2})

class Aclass(HasTraits):
    bclass = Instance(Bclass)
    abc = Str

    options = Property(Str, depends_on='bclass.options')
    def _get_options(self):
        return self.bclass.options.keys()

    traits_view = View(
        Item(name='abc', editor=CheckListEditor(name='options')),
    )

In this case, the view is updated whenever the content of the options dictionary changes.