def on_change(instance, traits, function, weak=None):
"""
Register a listener to an object.
:param traits: either a `string`, `traity.events.listenable`, or a tuple of strings and listenables.
:param function: function to call when event with target `target` is triggered.
:param instance: The object to listen to events for.
"""
target = concat_targets(traits, "changed")
events(instance).listen(target, function, weak=weak)
def on_change(instance, traits, function, weak=None):
'''
Register a listener to an object.
:param traits: either a `string`, `traity.events.listenable`, or a tuple of strings and listenables.
:param function: function to call when event with target `target` is triggered.
:param instance: The object to listen to events for.
'''
target = concat_targets(traits, 'changed')
events(instance).listen(target, function, weak=weak)
def test_concat_targets(self):
self.assertEqual(concat_targets('a', 'b'), ('a', 'b'))
self.assertEqual(concat_targets(('a',), 'b'), ('a', 'b'))
self.assertEqual(concat_targets('a', ('b',)), ('a', 'b'))
self.assertEqual(concat_targets(('a', 'b'), None), ('a', 'b'))
self.assertEqual(concat_targets(None, ('a', 'b')), ('a', 'b'))
self.assertEqual(concat_targets(('c'), ('a', 'b')), ('c', 'a', 'b'))
self.assertEqual(concat_targets(('c','a'), ('b')), ('c', 'a', 'b'))
self.assertEqual(concat_targets(None, None), None)
def on_trait_change(traits):
"""
Statically Register a listener to a class::
@on_trait_change('attr')
def attr_changed(self, event):
print 'hello!'
.
"""
target = concat_targets(traits, "changed")
def decorator(func):
if not isinstance(func, StaticListener):
func = StaticListener(func)
func.add_listener(target, func.function)
return func
return decorator
def on_trait_change(traits):
'''
Statically Register a listener to a class::
@on_trait_change('attr')
def attr_changed(self, event):
print 'hello!'
.
'''
target = concat_targets(traits, 'changed')
def decorator(func):
if not isinstance(func, StaticListener):
func = StaticListener(func)
func.add_listener(target, func.function)
return func
return decorator
def decorator(listener):
target = concat_targets(self.target, "error")
self.add_listener(target, listener)
return listener
def decorator(listener):
target = concat_targets(self.target, 'error')
self.add_listener(target, listener)
return listener
