Package Products :: Package ZenUtils :: Module observable :: Class IObservable |
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# Class IObservable

source code

    zope.interface.Interface --+
                               |
                              IObservable

Classes that implement the IObservable interface agree to provide the Observer pattern for object attribute changes.

Instance Methods | [hide private]
attachAttributeObserver(self, name, observer) Attaches an observer that will be notified when the specified attribute changes value. | source code
detachAttributeObserver(self, name, observer) Removes an observer from watching the specified attribute. | source code
notifyAttributeChange(self, name, oldValue, newValue) Notify all registered observers that an attribute has changed value. | source code

Method Details | [hide private]

### attachAttributeObserver(self, name, observer) | source code
Attaches an observer that will be notified when the specified attribute changes value. @param name the attribute name to observer @param observer the observer/listener to be notified @type observer callable

### detachAttributeObserver(self, name, observer) | source code
Removes an observer from watching the specified attribute. @param name the attribute name to remove the observer from @param observer the observer/listener to be removed

### notifyAttributeChange(self, name, oldValue, newValue) | source code
    Notify all registered observers that an attribute has changed value.
    Register observers must be a Python callable and will receive the
    following keyword arguments:
        observable - a reference to the observed object
        attrName - the attribute name that has changed
        oldValue - the previous value
        newValue - the new value

    @param name the attribute name that has changed
    @param oldValue the old attribute value
    @param newValue the new attribute value