class CallbackMixin(object):
"""
A mixin that provides a utility for attaching callback
functions to methods
"""
def __init__(self):
self._callbacks = CallbackContainer()
def add_callback(self, function):
self._callbacks.append(function)
def remove_callback(self, function):
self._callbacks.remove(function)
def notify(self, *args, **kwargs):
for func in self._callbacks:
func(*args, **kwargs)
class CallbackMixin(object):
"""
A mixin that provides a utility for attaching callback
functions to methods
"""
def __init__(self):
self._callbacks = CallbackContainer()
def add_callback(self, function):
self._callbacks.append(function)
def remove_callback(self, function):
self._callbacks.remove(function)
def notify(self, *args, **kwargs):
for func in self._callbacks:
func(*args, **kwargs)
def __init__(self):
self.artists = []
self.empty_callbacks = CallbackContainer()
self.change_callbacks = CallbackContainer()
self._ignore_empty_callbacks = False
self._ignore_change_callbacks = False
class LayerArtistContainer(object):
"""A collection of LayerArtists"""
def __init__(self):
self.artists = []
self.empty_callbacks = CallbackContainer()
self.change_callbacks = CallbackContainer()
self._ignore_empty_callbacks = False
self._ignore_change_callbacks = False
def on_empty(self, func):
"""
Register a callback function that should be invoked when
this container is emptied
"""
self.empty_callbacks.append(func)
def on_changed(self, func):
"""
Register a callback function that should be invoked when
this container's elements change
"""
self.change_callbacks.append(func)
def _duplicate(self, artist):
for a in self.artists:
if type(a) == type(artist) and a.layer is artist.layer:
return True
return False
def append(self, artist):
"""Add a LayerArtist to this collection"""
self.artists.append(artist)
artist.zorder = max(a.zorder for a in self.artists) + 1
self._notify()
def remove(self, artist):
"""Remove a LayerArtist from this collection
:param artist: The artist to remove
:type artist: :class:`LayerArtistBase`
"""
if artist in self.artists:
self.artists.remove(artist)
artist.remove()
self._notify()
def clear(self):
"""
Remove all layer artists from this collection
"""
for artist in self.artists:
artist.remove()
if six.PY2:
self.artists[:] = []
else:
self.artists.clear()
def clear_callbacks(self):
"""
Remove all callbacks
"""
self.empty_callbacks.clear()
self.change_callbacks.clear()
def _notify(self):
if not self._ignore_change_callbacks:
for cb in self.change_callbacks:
cb()
if not self._ignore_empty_callbacks and len(self) == 0:
for cb in self.empty_callbacks:
cb()
def pop(self, layer):
"""Remove all artists associated with a layer"""
to_remove = [a for a in self.artists if a.layer is layer]
for r in to_remove:
self.remove(r)
return to_remove
@property
def layers(self):
"""A list of the unique layers in the container"""
return list(set([a.layer for a in self.artists]))
@contextmanager
def ignore_empty(self):
"""
A context manager that temporarily disables calling callbacks if
container is empty.
"""
try:
self._ignore_empty_callbacks = True
yield
finally:
self._ignore_empty_callbacks = False
@contextmanager
def ignore_change(self):
"""
A context manager that temporarily disables calling callbacks if
container is changed.
"""
try:
self._ignore_change_callbacks = True
yield
finally:
self._ignore_change_callbacks = False
@contextmanager
def ignore_callbacks(self):
try:
self._ignore_change_callbacks = True
self._ignore_empty_callbacks = True
yield
finally:
self._ignore_change_callbacks = False
self._ignore_empty_callbacks = False
def __len__(self):
return len(self.artists)
def __iter__(self):
return iter(sorted(self.artists, key=lambda x: x.zorder))
def __contains__(self, item):
return any(item is a.layer for a in self.artists)
def __getitem__(self, layer):
if isinstance(layer, int):
return self.artists[layer]
return [a for a in self.artists if a.layer is layer]
def __init__(self):
self._callbacks = CallbackContainer()
def __init__(self):
self.artists = []
self.empty_callbacks = CallbackContainer()
self.change_callbacks = CallbackContainer()
self._ignore_callbacks = False
class LayerArtistContainer(object):
"""A collection of LayerArtists"""
def __init__(self):
self.artists = []
self.empty_callbacks = CallbackContainer()
self.change_callbacks = CallbackContainer()
self._ignore_callbacks = False
def on_empty(self, func):
"""
Register a callback function that should be invoked when
this container is emptied
"""
self.empty_callbacks.append(func)
def on_changed(self, func):
"""
Register a callback function that should be invoked when
this container's elements change
"""
self.change_callbacks.append(func)
def _duplicate(self, artist):
for a in self.artists:
if type(a) == type(artist) and a.layer is artist.layer:
return True
return False
def append(self, artist):
"""Add a LayerArtist to this collection"""
self.artists.append(artist)
artist.zorder = max(a.zorder for a in self.artists) + 1
self._notify()
def remove(self, artist):
"""Remove a LayerArtist from this collection
:param artist: The artist to remove
:type artist: :class:`LayerArtistBase`
"""
if artist in self.artists:
self.artists.remove(artist)
artist.remove()
self._notify()
def clear(self):
"""
Remove all layer artists from this collection
"""
for artist in self.artists:
artist.remove()
if six.PY2:
self.artists[:] = []
else:
self.artists.clear()
def clear_callbacks(self):
"""
Remove all callbacks
"""
self.empty_callbacks.clear()
self.change_callbacks.clear()
def _notify(self):
if self._ignore_callbacks:
return
for cb in self.change_callbacks:
cb()
if len(self) == 0:
for cb in self.empty_callbacks:
cb()
def pop(self, layer):
"""Remove all artists associated with a layer"""
to_remove = [a for a in self.artists if a.layer is layer]
for r in to_remove:
self.remove(r)
return to_remove
@property
def layers(self):
"""A list of the unique layers in the container"""
return list(set([a.layer for a in self.artists]))
@contextmanager
def ignore_empty(self):
"""A context manager that temporarily disables calling callbacks if container is emptied"""
try:
self._ignore_callbacks = True
yield
finally:
self._ignore_callbacks = False
def __len__(self):
return len(self.artists)
def __iter__(self):
return iter(sorted(self.artists, key=lambda x: x.zorder))
def __contains__(self, item):
return any(item is a.layer for a in self.artists)
def __getitem__(self, layer):
if isinstance(layer, int):
return self.artists[layer]
return [a for a in self.artists if a.layer is layer]
def __init__(self):
self._callbacks = CallbackContainer()