#------------------------------------------------------------------------------
# Copyright (c) 2012, Enthought, Inc.
# All rights reserved.
#------------------------------------------------------------------------------
from abc import ABCMeta, abstractmethod
from traits.api import HasTraits, Enum, Instance, List
from .image_provider import Image
from .resource import Resource
[docs]class IconImage(HasTraits):
""" An object representing an image in an icon.
Instances of this class are used to populate the `images` list of
an `Icon` instance. Instances of this class should be treated as
read-only once they are created.
"""
#: The widget mode for which this icon should apply.
mode = Enum('normal', 'active', 'disabled', 'selected')
#: The widget state for which this icon should apply.
state = Enum('off', 'on')
#: The image to use for this icon.
image = Instance(Image)
[docs] def snapshot(self):
""" Get a snapshot dictionary for this icon image.
"""
snap = {}
snap['mode'] = self.mode
snap['state'] = self.state
snap['image'] = self.image.snapshot() if self.image else None
return snap
[docs]class Icon(Resource):
""" A resource object representing an icon.
Instances of this class are created by an `IconProvider` when it
handles a request for an icon. Instances of this class should be
treated as read-only once they are created.
"""
#: The list of icon images which compose this icon.
images = List(IconImage)
[docs] def snapshot(self):
""" Get a snapshot dictionary for this icon.
"""
snap = super(Icon, self).snapshot()
snap['images'] = [image.snapshot() for image in self.images]
return snap
[docs]class IconProvider(object):
""" An abstract API definition for an icon provider object.
"""
__metaclass__ = ABCMeta
@abstractmethod
[docs] def request_icon(self, path, callback):
""" Request an icon from this provider.
Parameters
----------
path : str
The requested path of the icon, with the provider prefix
removed. For example, if the full icon source path was:
`icon://myprovider/icons/foo` then the path passed to this
method will be `icons/foo`.
callback : callable
A callable which should be invoked when the icon is loaded.
It accepts a single argument, which is the loaded `Icon`
object. It is safe to invoke this callable from a thread.
"""
raise NotImplementedError