Source code for atom.delegator

#------------------------------------------------------------------------------
# Copyright (c) 2013-2017, Nucleic Development Team.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file LICENSE, distributed with this software.
#------------------------------------------------------------------------------
from .catom import (
    Member, PostGetAttr, PostSetAttr, DefaultValue, Validate, PostValidate
)


[docs]class Delegator(Member): """ A member subclass which delegates all work to a wrapped member. The only behaviors not delegated are GetAttr and SetAttr. Subclasses should override behavior as needed to suit their needs. In order to change a particular mode, the relevant change method must be called via super(Delegator, ...). """ __slots__ = 'delegate' def __init__(self, delegate): """ Initialize a DeclarativeProperty. Parameters ---------- delegate : Member The Atom Member which provides the behavior for the property. The member should use standard slot behavior semantics. """ self.delegate = delegate sup = super(Delegator, self) sup.set_post_getattr_mode(PostGetAttr.Delegate, delegate) sup.set_post_setattr_mode(PostSetAttr.Delegate, delegate) sup.set_default_value_mode(DefaultValue.Delegate, delegate) sup.set_validate_mode(Validate.Delegate, delegate) sup.set_post_validate_mode(PostValidate.Delegate, delegate)
[docs] def add_static_observer(self, observer): """ Add a static observer to the member. This method also adds the static observer to the delegate. """ super(Delegator, self).add_static_observer(observer) self.delegate.add_static_observer(observer)
[docs] def remove_static_observer(self, observer): """ Remove a static observer from the member. This method also removes the static observer from the delegate. """ super(Delegator, self).remove_static_observer(observer) self.delegate.remove_static_observer(observer)
[docs] def set_name(self, name): """ Assign the name to this member. This method keeps the name of the delegate member in sync. """ super(Delegator, self).set_name(name) self.delegate.set_name(name)
[docs] def set_index(self, index): """ Assign the index to this member. This method keeps the index of the delegate member in sync. """ super(Delegator, self).set_index(index) self.delegate.set_index(index)
[docs] def set_post_getattr_mode(self, mode, context): """ Set the post getattr mode for the member. This method proxies the change to the delegate member. """ self.delegate.set_post_getattr_mode(mode, context)
[docs] def set_post_setattr_mode(self, mode, context): """ Set the post getattr mode for the member. This method proxies the change to the delegate member. """ self.delegate.set_post_setattr_mode(mode, context)
[docs] def set_default_value_mode(self, mode, context): """ Set the default value mode for the member. This method proxies the change to the delegate member. """ self.delegate.set_default_value_mode(mode, context)
[docs] def set_validate_mode(self, mode, context): """ Set the default value mode for the member. This method proxies the change to the delegate member. """ self.delegate.set_validate_mode(mode, context)
[docs] def set_post_validate_mode(self, mode, context): """ Set the default value mode for the member. This method proxies the change to the delegate member. """ self.delegate.set_post_validate_mode(mode, context)
[docs] def clone(self): """ Create a clone of the declarative property. This method also creates a clone of the internal delegate for mode handlers which use the original delegate as the context. """ clone = super(Delegator, self).clone() delegate = self.delegate clone.delegate = delegate_clone = delegate.clone() mode, old = clone.post_getattr_mode if old is delegate: clone.set_post_getattr_mode(mode, delegate_clone) mode, old = clone.post_setattr_mode if old is delegate: clone.set_post_setattr_mode(mode, delegate_clone) mode, old = clone.default_value_mode if old is delegate: clone.set_default_value_mode(mode, delegate_clone) mode, old = clone.validate_mode if old is delegate: clone.set_validate_mode(mode, delegate_clone) mode, old = clone.post_validate_mode if old is delegate: clone.set_post_validate_mode(mode, delegate_clone) return clone