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Observers property in TComponent

Hi Delphi XE2 TComponent has a new "Observers" property. Unfortunately the help entries for this are empty. Does anybody know what this new property is good for and how to use it? Edit: Well i know that it is related to LiveBindings, but I would love to know a bit more about it, and since I have no access to XE2 source code, I can't investigate myself.

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iamjoosy Avatar asked Sep 02 '11 17:09

iamjoosy


3 Answers

It is related to LiveBindings. A rather cool but extensive subject, explained in the new DocWiki for XE2.

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Rudy Velthuis Avatar answered Sep 28 '22 01:09

Rudy Velthuis


The Delphi implementation of the observer pattern is explained here:

http://blogs.teamb.com/joannacarter/2004/06/30/690

I'll update the answer with more details as soon as I've had a chance to look at the source code.

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Johan Avatar answered Sep 28 '22 00:09

Johan


The Delphi XE7 documentation now goes much deeper into the details of the Observers:

Observers is a read-only property that returns the TObservers added to the TComponent, in order to use the notifications provided by the observers either with LiveBindings or for the developers' own purposes.

Note that the Observer in Fringe can be seen on the scene of many Pattern-related events.


Side note:

Observers might also be able to detect situations where a EProgrammerNotFound exception must be thrown by the RTL.

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mjn Avatar answered Sep 28 '22 02:09

mjn