Dynamically changing trait - traits

Question

Is it possible to have two classes
class SimulationDigitizer(HasTraits):
width = Int(1920)
height = Int(1080)
name = 'Simulation'
class FileDigitizer(HasTraits):
Filename = File
name = 'File'
and another class 'Digitizer' having an attribute (or trait) UserDigitizer whose edition dialog will propose a drop-down list with 'Simulation' and 'File' and, depending on the choice, the instance edition of either FileDigitizer or SimulationDigitizer and get the result in UserDigitizer ?
Thanks

Answer 1

Thanks Jonathan, you are right, the problem is to select the appropriate subcomponent among many possible.
I ended with the following code, I guess it can be improved in many ways. I am new both to Python and Traits.
# -*- coding: utf-8 -*-
from traits.api import HasTraits, Int, File, Enum, Instance
from traitsui.api import View, Item, Handler, HGroup, InstanceEditor
class UserComponent ( HasTraits ):
""" An empty class from which all user component classes are
derived.
"""
pass
class SimulationDigitizer(UserComponent):
width = Int(1920)
height = Int(1080)
nature = 'Simulation'
class FileDigitizer(UserComponent):
filename = File
nature = 'Reading a file'
UserDigitizers = [FileDigitizer, SimulationDigitizer]
class UserComponentHandler(Handler):
def __init__(self,_user_components_dict):
Handler.__init__(self)
self._user_components_dict = _user_components_dict
def object_user_component_nature_changed ( self, info ):
# Find new UserComponent class from string in user_component_nature
new_user_component = self._user_components_dict[info.object.user_component_nature]
# If different, change user_component value
if info.object.user_component is not new_user_component:
info.object.user_component = new_user_component
class Digitizer(HasTraits):
user_component_nature = Enum([x().nature for x in UserDigitizers])
_user_file_digitizer = FileDigitizer()
_user_simulation_digitizer = SimulationDigitizer()
# Dictionary with keys = nature and values = user digitizers
_user_digitizers_dict = {x.nature: x for x in [_user_file_digitizer,_user_simulation_digitizer]}
user_component = Enum(_user_file_digitizer,_user_simulation_digitizer)
view = View(HGroup(Item('user_component_nature',
label = 'Nature'),
Item('user_component',
show_label = False,
editor = InstanceEditor(label = 'Edit',
kind = 'modal'))),
handler = UserComponentHandler(_user_digitizers_dict))
d = Digitizer()
if __name__ == '__main__':
d.configure_traits()