[Overview][Constants][Types][Procedures and functions][Variables][Index] Reference for unit 'Intuition' (#aros)


This method tells an object to broadcast an attribute change to its broadcast list.


Source position: intuition.pas line 1770

const OM_NOTIFY = OM_Dummy + 7;


This method tells an object to broadcast an attribute change to a set of target objects using OM_UPDATE messages. The return value for this method is not explicitly defined.

The OM_NOTIFY method uses the TopUpdate message structure.

Most dispatchers do not handle the OM_NOTIFY message directly. Normally they inherit this method from a superclass, so they pass the OM_NOTIFY message on to the superclass dispatcher.

Although most dispatchers don't have to process OM_NOTIFY messages, most do have to send them. Whenever an object receives an OM_SET or OM_UPDATE about one of its attributes, it may need to notify other objects of the change. For example, when a prop gadget's PGA_Top value changes, its target object(s) need to hear about it.

If an object needs to notify other objects about a change to one or more of its attributes, it sends itself an OM_NOTIFY message. The OM_NOTIFY message will eventually end up in the hands of a superclass that understands OM_NOTIFY and it will send OM_UPDATE messages to the target objects.

See also



Message structure for OM_NOTIFY/OM_UPDATE





Perform method on object coerced to superclass.

Documentation generated on: 2017-01-10